■ Introduction to Research

Division of Environmental Science〓 Research Area : Hydraulic Engineering

Developing practical numerical flood simulationsin urban areas
Numerical simulations of floods in urban areas are useful for establishing evacuation programs and revising future city planning.
In the present study, a set of shallow water equations was used tosimulate the swift current on the streets to characterize horizontal
flow diversion and concentration considering actual building configurations. The finite volume method was applied to an unstructured
triangular mesh system to express the orientation and physicalcharacteristics of each building based on a detailed city map. Recently, we conducted laboratory experiments and applications for
actual events to develop more accurate and practical simulationsof floods in urban areas.

ALB measurements of channel bathymetry for rivermanagement tasks〓 Prof. (Special appointment)
MAENO Shiro〓 Assoc. Prof.
YOSHIDA Keisuke〓 Assoc. Prof.
AKOH Ryosuke

Recently, an airborne laser bathymetry (ALB) system using simultaneously pulsed lasers of two
kinds (green and near infrared types) has attracted the attention of river and coastal engineers
for use as an efficient cost-saving surveying tool. This technology is effective for high-resolution
measurement of planar bathymetry including the underwater bed profile. For this study, we applied a developed ALB system and examined the accuracy in the targeted section by comparing
the ALB data of 2 m horizontal resolution with existing survey data obtainedusing the conventional
method. Then we evaluated the effects of using
high-resolution ALB datain river flow analysis.

〓 Research Area : Geotechnical and Groundwater Engineering

Development of a simple and compact ground survey,
and in-situ test method
Since most of ground disasters occur in the unsaturated
region, soil tests and ground surveys on unsaturated
soils have been performed in order to measure thegeotechnical characteristics in unsaturated state. In addition, because it is necessary to evaluate quantitatively
the ground behavior at the time of ground disasters, thefollowing two themes are proposed: (1) an in-situ position test on a local scale with a simple and compact test
equipment, (2) a ground scale survey on a field scaleusing a non-destructive measurement method from theground surface. These would be contributed to evaluateof the safety of levees and slopes.

Development of monitoring method and numerical modeling method
for safety assessment of levee failure caused by seepage flow

〓 Prof.
TAKESHITA Yuji

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A monitoring method of the soil water content andpore water pressure by the infiltration behaviorof the river levee has been proposed for the purpose of contributing to the design and construction work of the river levee by appropriately evaluating the safety of river levee. The construction
method of a simulation model that can faithfully
reproduce the measurement data by saturation
and unsaturated infiltration analysis is developed.

〓 Research Area : Geotechnical and Groundwater Engineering

Developing a flexible and robust communication infrastructure system fora network of sensors used to remotely monitor damage during natural disasters
When a large-scale disaster occurs, it is crucial to havestable data transfer from a network of sensors. For aregion considered as high-risk, it is essential that thesensor network and data communication infrastructure be
installed and configured within several hours. This study
aims to develop a novel
sensor network and data
communication system fora test site for monitoringslope stability during intense precipitation events.

Establishing a technique for monitoring soil and groundwatercontamination using Frequency Domain Reflectometry
The purpose of this study is
to apply a measuring system
for subsurface contamination;
the FDR (Frequency Domain
Reflectometry) and FDR-V(with Vector network analyzer) system are employed tomeasure salinity and oil contaminants.

〓 Prof.
KOMATSU Mitsuru〓 Research Area : Geotechnical and Groundwater Engineering

Evaluation of the shear strength and deformation
characteristics of unsaturated soils
In order to prevent and reduce ground disasters in unsaturated earth structures (slope, levee, embankment, etc.)
caused by a rainfall, it needs to grasp the failure mechanism of soil structures due to the rain infiltration. For this,the shear tests with the water retention test in the laboratory are carried out according to the confining stress state
reproducing the state of ground as well as the deformation
mode of soil structures. The shear strength and deformation characteristics of the soil structures are examinedbased on the obtained results.

Applicability of water repellent soil to overlayer ofcapillary barrier using laboratory model test

〓 Assoc. Prof.
KIM Byeongsu

According to the past research results, since the maximum division length (LD) in the laboratory model experiment is less than
300cm, it would be difficult to realize the application to unsaturated ground structures. Thus, laboratory model tests for thecapillary barrier (CB) using the wettable and water repellent soils
according to rainfall condition in this study are performed, andthe applicability of the water repellent soil based on the obtained
results is examined. It is expected that the more stable unsaturated ground structure would be realized by applying the water
repellent soil to the sand layer of the CB system.

Graduate School of Environmental and Life Science, Okayama University

15

■ Introduction to Research〓 Research Area : Design of Steel Structures

Development of disaster prevention /mitigation technology using ICT technology
Disasters caused by typhoons, heavy rains and earthquakes
occur frequently in Japan. In my laboratory, we are developing
cutting-edge monitoring technology that Japan boasts to theworld, such as digital images and UAV laser measurement. By
using this technology to diagnose the soundness of infrastructures, we aim to create a country that is resilient to disasters. We
are developing 3D measurement methods using IoT technology
using UAVs and vehicles, and big data analysis technology using
artificial intelligence. This ICT (Information and communication
technology) makes it possible to discover slope collapse danger
points, measure deformation of riverbeds and river embankments, and visualize topographical changes on the seabed.

Development of civil engineering design, construction
and maintenance technology by BIM using 3D data
The ground survey results and structure design data are expressed
as a three-dimensional model in the virtual space on the computer.
This 3D data is used to perform a simulation to investigate howmuch seismic motion the structure can withstand. Furthermore, using AR (Augmented Reality) and VR (Virtual Reality) technologies,
we will create an efficient construction plan using automatically moving construction machines. In addition, by superimposing the data ofstructures measured at different times and investigating the location
where deformation has occurred, effective maintenance of the structure is possible. In this way, in my laboratory, you can learn the latest
civil engineering structure design, construction and maintenancetechnology in Japan using BIM (Building Information Modeling).

〓 Prof.
NISHIYAMA Satoshi〓 Research Area : Design of Steel Structures

Autonomous Kite-Sailing Energy Harvester: Innovationof offshore wind energy technology〓 Prof.
HIEJIMA Shinji

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Offshore wind power is the most promisingenergy source for a 100% renewable energy
society. But conventional wind turbines canharvest only small amounts of nearshore
wind energy due to the constraints of water
depth, long distance electric power transmission or competition against fishery industry.
The Autonomous Kite-Sailing Energy
Harvester generates power using a kite-sailing float with hydro turbines. Due to its
sailing-based highly movable system, it canharvest vast amounts of wind energy in the
pelagic zones and does not compete withfishing operations. The hydro turbines are
more compact than wind turbines, and thissystem does not require tall supporting towers or deep water anchoring.
We also have been developing the Hydro-VENUS turbine to apply to the Autonomous Kite-Sailing Energy Harvester. It is aflow-induced oscillation based hydro turbine
using columnar pendulums. Due to the simple geometrical shapes of the pendulums,
the Hydro-VENUS is cost-effective, lightweight and high-strength. Its patents are acquired in Japan, EU, US, China and Australia. We have established the Hydro-VENUS
Co., Ltd. start-up company.

Medium scale test model〓 Research Area : Design of Concrete Structures

Practical Application of Precast Concrete Member with
Super-High Durability Concrete
Objectives

In order to extend the lifespan of damaged bridge girders and to shorten

the period of traffic regulation during renewal construction, precast concrete
member with high durability is developed with blast furnace slag sand.
● PC (Prestressed Concrete) PCa member⇒ Strong to traffic load under water supply condition● RC (Reinforced Concrete) PCa member⇒ High resistance to freeze and thaw with out AE agent① BFS for High Durable Concrete② PC PCa Products
The characteristics of products are as follows;● High resistance against freezing and thawing
attack and fatigue in water● The loss of restress is small by small shrinkage
and creep of concrete● Establishment of Quality Standard of BFS● supplying system of BFS in the Domestic③ RC PCa Products〓 Prof.
AYANO Toshiki〓 Assoc. Prof.
FUJII Takashi

The characteristics of products are as follows;● High resistance to freezing and thawing attack without AE Agent● High resistance to chloride attack〓 Research Area : Architecture and Urban Spatial Planning

Discretionary architectural design review in North
American cities
I am analyzing the actual situation of sustainable infill type ofbuilding renewal in North America, the way of public participationin the development review process, and the actual living environment created by it. In particular, focusing on the case of renewalof individual buildings in the city center, from the viewpoint of thebalance of pre-determined standards (zoning, etc.) and discretionary development review, how can the living environment andlandscape that meet the needs and characters of the community
be achieved? Regarding that, we are examining effective frameworks and methods based on changes in the minutes and drawings of actual neighborhood meetings and design review public
hearings. Case study cities are Seattle, Toronto, Miami, etc.

Transfer of Development Rights system and its implementation for preservation of historical buildings〓 Assoc. Prof.
HORI Hirofumi

Many historic buildings have been demolished in the centerof Japan, and development is being conducted that does notmatch the characteristics of the area. In Japan, there are issues
such as the looseness of zoning and the existence of many development bonus systems, and there is a need for an effective
Transfer of Development Rights system. This study clarified theactual operation of Transfer of Development Rights system in
Vancouver from the viewpoint of historic building preservation.
As a result, strict zoning, discretionary development review
system, and rezoning system that enables development bonus
were cited as conditions for effectively operating the Transfer ofDevelopment Rights system.

Graduate School of Environmental and Life Science, Okayama University

17

■ Introduction to Research〓 Research Area : Vegetation Management

Study on conservation of ecosystem based on weed
vegetation and risk evaluation of invasive plants
In all over the world, raising concern about declining ecosystemservices by development and environmental pollution.
Weed vegetation supports theecosystemic base while contacting with human activities.
Therefore, we tackle improvementof environmental problem by understanding and utilizing a function of the weed vegetation.

On the other hand, thedisturbance of an ecosystem caused by theinvasive alien species isserious, too.
We propose ecosystemic
precise management
method by grasping seasonal variation in emergence and elucidating
the influence to environment of alien plants.

〓 Asst. Prof.
NAKASHIMA Yoshitaka〓 Research Area : Applied Ecology

Study on conservation ecology of endangered
freshwater animal species
Many native species of freshwater animals are endangered due to factors
such as the negative effects of river or agricultural channel improvements andpredation or competitive exclusion by invasive species. To conserve such endangered native freshwater animals, we have to clarify the basic ecology (e.g.,
reproductive behavior and habitat preference) and then develop effective conservation methods. In our recent studies, we clarified the habitat preferenceof the endangered bitterling fish species (Rhodeus atremius suigensis; Fig.
1) in agricultural channels, and wintering site environment of the endangered
Nagoya Daruma Pond Frog (Pelophylax porosus brevipodus) inhabiting paddy fields. Also, we have studied the effectiveness of restoration methods in Fig. 1 An endangered bitterlingfish (R. atremius suigensis).
agricultural channels for freshwater fish conservation.

Study on ecology of invasive crayfish species and development ofeffective eradication methods〓 Prof.
NAKATA Kazuyoshi
Fig. 2 An endangered Japanese
crayfish (C. japonicus) being
preyed on by an invasive crayfish(P. leniusculus).

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Invasive freshwater animal species have a negative
impact on native species. Especially, the impact ofinvasive crayfish is strong. In our previous studies,
the invasive North American crayfish species (Pacifastacus leniusculus) was shown to be able to cause
species replacement for the endangered native
Japanese crayfish species (Cambaroides japonicus)
due to direct predation (Fig. 2) or in competition for
preferred sized shelters. In the present study, we
have tried to clarify the life cycle of the North American invasive crayfish species Procambarus clarkii
inhabiting water areas in Japan and also to develop
effective eradication methods.

〓 Research Area : Applied Ecology

Coexistence mechanisms among native, congenetic
plant species
Plant species is the most important part of biodiversity and it
provides various ecosystem functions. To clarify the coexistence mechanism of closely related plant species is a challenging subject because they often share a very similar resource
demand and reproductive biology. We have examined thecoexistence mechanism between native Commelina species
under pollinator-mediated competition (Fig. 1). Our studies arebasically based on field observations and combined with ex- Fig. 1. Commelina communis (left) and C.
periments of population genetics and theoretical models. Now, communis f. ciliata (right).
we are working on elucidating the mechanisms that the evolution of plant mating systems promote the coexistence among
related species.

Population persistences of native plant species in theurban environment.

〓 Asst. Prof.
KATSUHARA Koki

Fig. 2. Rural (left) and urban (right) populationsof Commelina communis.

From now and probably in the future, land-use
change has been thought to be the most severe
driver of changes in biodiversity. Urbanization,
which is intensifying human impacts, is a major
driver of habitat loss for plants and pollinators.
Our study species, Commelina communis, islargely distributed from rural to urban areas (Fig. 2)
although many habitats of native plant species arelost related to urbanization. We are now examining what determines the robustness or vulnerability for human impact via focusing on plant mating
systems and plant-pollinator interaction.

〓 Research Area : Soil Management

How to reduce greenhouse gas emissions from soil
amended with organic matter?
Agriculture is responsible for emissions of greenhousegases such as carbon dioxide (CO2) and nitrous oxide(N2O). Production of these gases in soil results from thebiological processes like organic matter decomposition,
nitrification and denitrification. These processes are regulated by easily decomposable carbon, mineral nitrogen,temperature, pH and moisture content in soil. We aim atanalyzing effects of these parameters on CO2 and N2Oemissions. In particular, we are interested in agriculturalsoil amended with livestock compost.

Analysis of groundwater contamination with inorganic N in Central
Vietnam by using stable isotopes and microbial technologies〓 Prof.
MAEDA Morihiro

High concentrations of inorganic nitrogen (NH4-N
and/or NO3-N) were found in groundwater below
vegetable fields in the downstream areas of the
Huong River, Central Vietnam. The objective of
the study is to determine the contamination sources and mechanisms of nitrogen contaminationin groundwater by using 15N natural abundance(δ15N) and functional genes of microorganisms.
We have developed a new method to collect
NH4-N, NO3-N, and organic N in water samples forδ15N analysis. Functional genes like narG, napK,and nosZ are quantified to obtain the information
on nitrogen dynamics in deep soil.

Graduate School of Environmental and Life Science, Okayama University

19

■ Introduction to Research〓 Research Area : Agricultural Land Engineering

Installing artificial macropore to enhance infiltration and increaseorganic matter in soils.
Soil is the largest carbon storage body at terrestrial area.
Our previous research showed that macroporous soils
conduct surface water without clogging and that bypass
flow by macropores segregated organic matter from thesurface. Organic matters will be effectively conserved bythese physical processes, which contributed greatly tocarbon storage as well as bio-chemical processes.
FigureRainfall was effectively conducted byartificial macropore which contributed to organic matter
conservation.

Linear Macropore Installation for Reducing Red-soil Erosion
at Sugarcane Field.

〓 Prof.
MORI Yasushi
FigureSurface water caused by heavy rain
removes nutrient rich surface soil, but macropore
structure reduces them greatly.

Red-soil erosion in sugarcane fields has
been reported as a significant agriculturaland environmental problems in Ishigaki Island in Okinawa, where such erosion has
led to loss of nutrient-rich agriculture soil andalso negatively impacted coral reefs. We
introduced linear-macropore to the field. The
result showed that the erosion almost cancelled the conservative land management
and installation of linear macropre reduced
surface water and erosion amount to 1/7.

〓 Research Area : Agricultural Land Engineering

Observation and Modelling of Soil – Plant – Atmosphere Interaction
for Sustainable Land Management

My research interest is “soil-plant-atmosphere interaction” in regional to country scale: how land
surface condition affects local rainfall and climate through water and energy fluxes between land
and atmosphere. Current research topics are (i) estimation of pedotransfer function and dielectric
behavior of soils in regional scale to improve the algorithm of microwave satellite remote sensingof soil moisture; (ii) development of an integrated system of remote sensing, field observation,and numerical model simulations (data assimilation) for environmental monitoring & projection;(iii) process-based study on the mechanism of the soil-plant-atmosphere interaction; (iv) assessment of land-use change and global warming on food production and water resources; etc.
Research methodology involves field survey, in-situ observation, laboratory experiment, satellite
remote sensing, and numerical model development & simulations. Capacity building and implementation into the society especially in the developing countries are also the key.

〓 Asst. Prof.
TSUJIMOTO Kumiko20〓 Research Area : Terrestrial Information Management

Study on rural environment using terrestrial information processing
In recent years global environmental problems suchas desertification, the forest decrease, the degradation of the farmland have become serious, also in
our imminent place, local environmental problems
such as the Satoyama landscape(rural landscape)have become serious. These environmental problems have large or small spatial scale, but those are
all phenomenon occuring on the real field, and thething which can describe such spatial phenomenon is a map (geography space information). In ourlaboratory, we have been trying to analyze various
environmental problems using a digital map and the artificial satellite image which we can treat
with a computer.

Monitoring of land use/cover change and mathematicalmodeling
Land use/cover is greatly influenced by local environment and has
a significant influence at the same time to area environment, also
greatly influenced by the global environment and have a significant
influence on the global environment. When thinking about local andglobal environment, It become fundamental problem how to control
land use/cover. This study aims to bring useful result for planning, tomake clear the cause and effect relationship of land use/cover change
by modeling it.

〓 Prof.
MORITA Hidenori〓 Research Area : Irrigation and Drainage

Study on evapotranspiration and soil water content forwater resources
Evapotranspiration and soil water content are very important as key factorsof hydrologic cycle and water resources. In our laboratory, the following two
researches on evapotranspiration and soil water are carried out: (1) There aresome methods for estimating the evapotranspiration, it, however, is not so convenient to use those methods because they often needs the meteorological data at
two heights. We aim to develop the simple method for estimating evapotranspiration using one heig ht meteorological data. (2) We estimate the potential water
resources for agricultural products using soil water content, evapotranspiration,and other data.
The results of these researches
would be contribute to not only agriculture and irri gation but also therecent variation of hydrologic cycle.

Developing a technique for estimating soil and groundwater contamination
utilizing permittivity, thermal properties, and other physical properties〓 Prof.
MOROIZUMI Toshitsugu

Soil and groundwater contamination by NAPLs (nonaqueous-phase liquids) has become a serious environmental issue in Japan and aroundthe world. It is difficult to detect or monitor the transport rates of NAPLs
under field conditions, because the NAPLs are immiscible with water. In
addition, because chemical solutions are often mixed with NAPLs, thedetection of contaminant is more complicated. In our laboratory, we aim
to develop the fundamental techniques to detect the soil and groundwater contaminated with both NAPLs and chemical solutions using somephysical properties such as permittivity, thermal properties, and self potential.

Graduate School of Environmental and Life Science, Okayama University

21

■ Introduction to Research〓 Research Area : Irrigation and Drainage

Study on balancing agricultural practices with nature
to protect water resources
Agriculture is essential to modern civilization but often has unintended negative effects upon the natural environment,
especially regarding water quality. Overuse of fertilizers is costly both economically and environmentally. We evaluatedregional agricultural cultivation practices to determine optimal irrigation and fertilizer, timing and amounts, to maximize
production while minimizing nutrient-driven eutrophication of local water bodies.
Agricultural fields are used not only by farmers, but also by wildlife. We studied the effects of the Tundra Swan on
nutrient levels in rice paddies. Tundra Swans, from Far East Russia, overwinter in flooded paddy-fields from November to March. They roost in the paddy-fields at night and forage nearby in other agricultural fields during the day. We
measured Tundra Swan manure-nutrient component of paddy-field soil and water nutrient concentrations to determine
optimal farmer-applied fertilizer amendments required for rice production, without over-applying.
Our ultimate goal is to find a win-win-win relationship among the environment, humans (farmers), and wildlife with respect to water quality.

Study on irrigation management for stabilizing agricultural production〓 Assoc. Prof.
SOMURA Hiroaki

Water is critical for agriculture and irrigation practice is an important part of farm management. Irrigation water isoften wasted or poorly applied (i.e., amount or timing) leading to lowered agricultural production from poor crop healthor damage. It is important to evaluate water resource availability to effectively manage irrigation timing and amounts
required for efficient crop production.
We assessed watershed-level water availability upon a local irrigation scheme. Data were gathered through fieldobservations and farmer questionnaires. Data were evaluated by computer modeling. At the watershed level, irrigationwater allocation is spatially unbalanced among upstream, midstream, and downstream observations. We attempted todetermine alternative management methods and/or improve current methods for efficiently allocating irrigation water
equally to the fields.
By improving irrigation water use efficiency through better allocation management, there is an apparent increase in water
availability. This will lead to an expanded cultivation area, higher production, and ultimately, better agricultural stability.

〓 Research Area : Catchment Hydrology

Development of real-time forecasting system usinghydrological model and data assimilation technique

Recently, flood damage has become serious problem around the world due to the changes in climate condition. Flood forecast system using hydrological model is useful tool to mitigate the flood damage. One of the main topics in our research team is to develop real-time flood
forecasting system using distributed/lumped hydrological models and radar rainfall data. In addition, to improve forecasting accuracy, we
introduce data assimilation techniques like Kalman Filter and Particle Filter into the forecasting system, and investigate the uncertainties
caused by hydrological modeling including parameter setting and by weather/climate forecasting data as an input to the hydrological models.

Fig u r e 1 S p a tia l
distribution of rainfall based on radar
data

Figure 2 Example
of real-time flood
forecasting.

The impact assessment of climate change on hydrological cycle using hydrological model andclimate scenarios. -Uncertainty analysis of impacts of climate change on snow processesThe impact of climate change on snow water equivalent (SWE) and its uncertainty were investigated in snowy areas in Japan by using a snow process modeland climate projections derived from general circulation models (GCMs). In particular, we examined how the uncertainty due to GCMs propagated through thesnow model, which contained nonlinear processes defined by thresholds. The uncertainty analysis demonstrated that when the peaks of the distributions ofdaily mean temperature projected by GCMs cross the key thresholds set in the snow model, the GCM uncertainty, even if tiny, can be amplified by the nonlinear propagation through the snow process model. This amplification results in large uncertainty in projections of CC impact on snow processes.

〓 Prof.
CHIKAMORI Hidetaka〓 Assoc. Prof.
KUDO Ryoji

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Figure 3 Changes in
SWE for the emission
scenarios: near future,
RCP2.6, RCP4.5, and
RCP8.5.

Figure 4 Projection
ranges of regionallyaveraged changes in
winter-mean temperature and SWE.

〓 Research Area : Design of Environmental Infrastructures

Reliability analysis of geo-structures
The stability of the geo-structures, and the natural slopes need to beanalyzed against the severe natural disasters, namely, the earthquakes
and heavy rains. Based on the analytical results, the appropriate counter measures can be determined. The concept of the reliability -based
design can be conveniently used for the decision making for the optimum alternative of the counter measures. The phenomena of the earthquakes and the rains are probabilistic, and the soil parameters havegreat variability. The reliability-based design can include the uncertainties into the designs. The reliability-based design method is mainly
applied to the earth-fill dams here. In Japan, about 160,000 of earth-filldams exist, and many of them are deteriorated, and the countermeasures are rushed. The reliability based-design method can determine
the priority of the earth-fill dams for the countermeasures.

Breached earth-fill dam byearthquake

3-D model of earth-fill dam site forstability analysis

Subsurface survey inside and under geo-structures〓 Prof.
NISHIMURA Shin-ichi

In-situ investigation of subsurface
layer by CPTu

Visualized strength distribution of subsurface layer-Probability for strength of soil to be low-

To evaluate the stability of the geo-structures, the subsurface survey
inside or under the geo-structures are important. The geophysical survey and the sounding tests are convenient. In our research, the electricCone Penetration Test (CPTu) is employed, and spatially long andshort-interval tests are mixed to efficiently evaluate the stability of anembankment. The geostatistical method is used to simulate the N value (strength value) distribution and to predict the weak locations inside
the embankments. The synthesized approach of the CPTu and theSurface Wave Method (SWM), which is one of the geophysical methods, is proposed to compensate for the shortcoming of each approachwith use of the geostatistical approach. Consequently, the insides ofthe embankments can be identified accurately, the high resolution of
the spatial distribution of the strength can be visualized.

〓 Research Area : Design of Environmental Infrastructures

Inverse analysis/data assimilation in civil engineering
Inverse analysis/data assimilation is a methodology to assimilate observation data into numericalsimulation models for realistic predictions and parameter identifications. We have developed inverse analysis methods and demonstrated the effectiveness by applying the methods to numericalexperiments, model tests, and actual construction projects. Figure 1 shows conceptual illustrationof cross-hole tomography which is typical inverse analysis method and is designed to visualize
subsurface in a non-destructive way. Figure 2 shows a comparison between the true image of theground and the reconstructed image by the cross-hole tomography.

True image
Figure 1 Cross-hole tomography

Reconstructed image

Figure 2 Comparison between true image andreconstructed image

Numerical Simulations using particle-based methods〓 Assoc. Prof.
SHUKU Takayuki

We have developed simulation codes of the moving particle semi-implicit (MPS) method to predict large deformation and failure behavior in geomaterials such as clay, sand, gravel and their
mixtures. Figure 3 shows a breach process of an earthen embankment due to overflow simulated by the developed MPS method.

Figure 3 Embankment breach process simulated by MPS method

Graduate School of Environmental and Life Science, Okayama University

23

■ Introduction to Research〓 Research Area : Management of Environmental Infrastructures

Interacting behaviors between ground and tunnel lining with voids
The maintenance of damaged irrigation tunnels
has become a major social concern; and thus,
evaluating the damage conditions of current tunnels is of crucial importance. Voids behind thetunnel lining may be created during or after construction by the conventional method, and thesevoids are the main factors in its failure. Hence,
it is imperative to comprehend the behaviors of
the ground, the tunnel lining and the voids. We
investigate the interacting behaviors between the
ground and a tunnel lining with voids by numericalsimulation and model tests.

Soil classification and correlation between Swedishweight sounding test results and strength parameter
Characterizing the properties of soils is of importance due
to design and maintenance concerns. These properties are
generally evaluated by laboratory and in-situ tests. Swedishweight sounding (SWS) tests are field tests used to obtainthe static penetration resistance. From the value of the resistance, the N-value, the unconfined compressive strength, andthe bearing capacity can be computed in order to evaluate
the soil strength. However, the strength parameters, such as
cohesion and the angle of internal friction, is not presented.
We investigate the soil classification and the correlation between the SWS test results and the strength parameters.

〓 Assoc. Prof.
SHIBATA Toshifumi〓 Research Area : Environmental Economics

Political economy of natural resource development
and its social impact in Southeast Asia
Recent economic growth in Southeast Asia has resulted in rapid depletion of natural resources. Yet many villagers near the
resource development area have not enjoyed improvementsin their lives as expected. Rather, some are even sacrificed byresource development projects and environmental conservation
policies. Our research examines how relevant stakeholders,such as governments, firms, villagers, and external agencies,
have interacted in certain resource development projects, suchas in the palm oil industry, pulp and paper industry, aquaculture,
forest conservation, and climate change adaptation, and how
this interaction has affected rural societies in Southeast Asia.

Harvesting oil palm by an Indonesian plantation worker(Sarawak, Malaysia, 2011)

Political processes and impacts of capitalization/financialization of nature in Southeast Asia

〓 Prof.
UBUKATA Fumikazu
Photo：Vanishing Tropical Forest inSoutheast Asia. Deforestation is believed
to be a significant source of carbon emission. (Sarawak, Malaysia, 2008)24

In recent years, many agencies in developing coutries have applied the approach to procure funds by
the use of financial instruments and direct payments
to mitigate environmental problems. Common examples include the use of carbon credits and systems
to pay for environmental services. Taking examples
from Southeast Asia, we examine processes thatlead to the formulation of these funding mechanisms,
and regards them as new developments that mainstream the commodification of nature (capitalization/
financialization of nature). At the same time, we also
examine its socioeconomic impacts and the changes
in governance of society and the environment.

〓 Research Area : International Rural Studies

Natural resource management in Asian countries
The commons are the cultural and natural resources accessible to all members of a community, which are not often managed by the"invisible hand" under a market system. It is
the local community that uses the commonssustainably, and endogenous self-organization plays a crucial role in forming norms
for sustainable resource exploitation. In thiscontext, my research interests focus on ruralcommunities in exploiting natural resources,
with study areas including Japan, Korea, China, and Vietnam.

Terraced paddy fields in Sapa, Vietnam(photo on July 2011)

Roles of endogenous self-organization in rural communities
Development is a process that involves not only money and agencies
but also people. The framework fororganizations in a rural community
can provide a clue to identifying whoshould be the real actors for sustainable rural development in either developed or less developed countries.

〓 Prof.
KIM Doo-Chul〓 Research Area : International Rural Studies

Conditions of participatory management of regional
resources
Farmland and irrigation and drainage facilities serve as agricultural infrastructure for paddy fields
and also contribute to society in other ways, for example, in reducing damage caused by heavy
rains or in developing visually favorable landscapes.
In recent decades, depopulation and aging of farmers have made it difficult for rural communities toproperly maintain this infrastructure. Therefore, there
is growing awareness that addressing this problem
requires new participation in the maintenance by
non-farmers. This research clarifies how rural communities actually maintain them and the factors affecting resident participation in maintenance.

Sustainable management of community-based
renewable energy〓 Assoc. Prof.
HONDA Yasuko

The expanding use of renewable energy can help prevent global
warming and reduce air pollution. Especially, community-based
renewable power derived from local initiatives (community energy) is expected to provide an alternative energy resource andserve as a catalyst for rural development. Between the 1950s
and 1960s, local communities became active in the constructionof small hydropower plants, many in the Chugoku region. This
study considers community energy projects in the Chugoku
region in Japan to illuminate what conditions have enabled thestudied organizations to succeed in securing resources needed
for the operation of their renewable energy plants.

Graduate School of Environmental and Life Science, Okayama University25

■ Introduction to Research〓 Research Area : Rural Planning

Construction of community planning theory led by residents
There have been cases where local residents in Japanese rural areas are embarking
on planning and revitalizational development
themselves in decades. In this research, we
focus on such movements within the settlements scale, and try to clarify difference andcharacteristics compared to the conventional administration-led form. The results will allow us to construct a planning theory peculiar to the Japaneserural area and can be expected to be useful as a guideline for future regional development.

Practical study on construction of measures to damage by wildlife based on planning perspective〓 Prof.
KUKI Yasuaki

The damage of agricultural products caused by wildlife suchas deer, wildboars and monkeys is becoming more serious in
Japanese rural area. The purpose of this research is to develop
the program to prevent from the damage that will lead to thefarmland conservation and the local communities' sustainability.
So we look into the consciousness of the residents in the affected area and the local government officers to clarify the issues
for solution, and consider the technical requirements for themeasures from the field survey. And we propose the solution of
the reduction of the damage at the municipal level and practicethem to verify the effects. The followings have been obtained from the previous studies: 1. the animals
prefer forested former paddy fields and abandoned farmland when they invade rural communities; 2. theeffectiveness of damage prevention can be improved by mowing abandoned farmland around the fences.
Based on these findings, we proposed a method for managing the marginal space when implementing
measures based on the fences to prevent agricultural damage by wildlife.

〓 Research Area : Physiological Plant Ecology

Stand dynamics and regeneration in natural forests
Tree population in the forest stand has been changed and maintained in the process of recruitment, survival, and growth of tree individuals,
which are determined by different disturbances and environmental factors including biotic and abiotic factors. The tree population show
slow temporal changes and spatial heterogeneity. Therefore, it is necessary to
conduct long-term and large-scale ecological researches for demonstrating tree
population, stand dynamics, and regeneration of the forests. I have conductedlong-term and large-scale ecological researches with adding tree ring analysis
in different natural forests. In beech forests of Japan, the researches have been
demonstrating dynamics of seedlings, understory trees, and canopy trees indifferent environmental conditions and the regeneration processes and mechanisms. In boreal forests of Mongolia, the researches have been demonstrating
effects of disturbance by forest fires and logging on the regeneration and degradation mechanisms after large-scale forest fires.
Boreal forest in Mongolia

Stand dynamics of secondary forests, Satoyama forests, and the conservation〓 Prof.
SAKAMOTO Keiji

Deciduous oak forest in Japan

26

Satoyama forests are secondary forests that were maintained by natural processes
and human's activities. They sustainably supplied bio-resources because regeneration
occurred after the harvesting. However, these Satoyama forests have been abandoned
since energy regimes changed from bio-resources of forests into fossil fuel around1960s. The abandonment has caused degradation of biodiversity, expansion of disease damages, and expansion of abandoned bamboo forests. On the other hand,these abandoned forests have been reevaluated as sustainable bio-resources recently.
Therefore, it is necessary to demonstrate the degradation processes of abandoned
forests and restore them. I have conducted ecological researches on the stand dynamics of Satoyama forests. The researches have been demonstrating degradation of
the stand structure and possibility of the artificial regeneration in pine forests damagedby pine wilt disease, expansion processes and mechanisms of abandoned bamboo
forests, and regeneration processes after logging in deciduous oak forests.

〓 Research Area : Physiological Plant Ecology

Study on water transport function of trees
In many tree-dominated ecosystems, drought-induced
hydraulic dysfunction has been associated with thesudden death of trees exposed to critical drought stressand is one of the most important factors that determines
the survival and distribution of trees. For various tree
species from arid to humid regions, therefore, we aim toelucidate the mechanism of maintaining the xylem watertransport under variable soil moisture conditions and thephysiological properties related to it.

↑ Optical microscope image of stem
cross section in Carpinus tschonoskii

Study on water use properties of trees growing in dry land

〓 Prof.
MIKI Naoko↑ Dominant tree species, Juniperus sabina,
growing in semiarid area of China

Plants acquire carbon through stomata of leaf forphotosynthesis, however, at the same time they lose
water through the stomata. Therefore, it is essential
for growth and survival to develop various properties
of suppressing water loss and rapidly supplementing
water loss. Water availability to plants in dry land
is limited. Therefore, it is important how efficiently
plants use water resources. For various species indry land, we aim to elucidate the water use properties and survival strategy of whole tree from variousorgan levels through evaluation of transpiration ofleaves, water transport properties of stems, water
absorption properties in roots. From these aspects,
we also work on research related to revegetation in
the water-limited environment of dry land.

〓 Research Area : Forest Ecology

Effects of intermittent reproduction on forest
regeneration in Fagus crenata
Fagus crenata is one of the characteristic tree species that produces
a large amount of flowers and seeds every few years. Environmental
factors, such as temperature and nutrient content, play a role in thisintermittent reproduction mechanism, but it is not clear how seed production will be affected by recent climate change. Seed production is
not only an important factor underpinning forest regeneration, but it
also provides food for the diverse organisms that survive within forest
ecosystems. We are attempting to clarify how this intermittent reproduction contributes to seedling regeneration through analysis basedon long-term surveys.

Study on the mechanism of environmental flower sex
determination in plants and its adaptive significance〓 Assoc. Prof.
MIYAZAKI Yuko

More than 90% of all seed plants do not havesex chromosomes and produce a combination ofhermaphroditic, female, and male flowers in an
individual plant. However, the sex determination
mechanism of individual flowers remains unclear
and how environmental factors (e.g., day length,
temperature, and nutrient status) act on sex determination. We are trying to elucidate the mechanisms of environmental factors, especially shortday conditions and nutrient status, that induce
hermaphroditic flower in relation to flower initiation,using Commelina communis f. ciliata. We also
examine the adaptive significance of these environmental conditions as signals of floral sex determination and attempt to predict future climate change impacts.

Graduate School of Environmental and Life Science, Okayama University

27

■ Introduction to Research〓 Research Area : Conservation of Aquatic Biodiversity

Taxonomy, nomenclature and conservation ofmolluscan taxa
Molluscs including shellfish, snails, slugs and so on are a very diversified animal group andconsist of more than 80,000 Recent species in the world, but their taxonomy and recognitionof species are still poorly understood. For example, Turbo sazae is one of the most well-known
marine snails in Japan since ancient age, but neverthelessthe species has long been misidentified with Turbo cornutus,
a species endemic to China, until recently and documented to
be unnamed in 2017. Another edible species Tegula kusairo
exhibited the similar case and it was described as a new
species in 2020. Furthermore, many species become extinct
or critically endangered by artificial environmental changes
before recognizing their presences by human beings. The
alpha-taxonomy of this group is thus highly important and an
urgent matter in terms of biodiversity conservation.
Turbo sazae Fukuda, 2017.

Collection and databasing of molluscan specimens〓 Assoc. Prof.
FUKUDA Hiroshi

Molluscs live in most habitats on land and in water. Because they have poor migration ability, they are closely
linked to the environmental conditions of the place thanany other organisms, and are useful for understanding thehistorical transition and current status of environment. It isthe best as an environmental indicator. We are collecting
molluscs from all over Japan, preparing specimens, andmaking a database. As of June 2021, about 30,000 lots ofspecimens have been registered.
Sunetta beni Fukuda, Ishida, Watanabe,
Yoshimatsu & Haga, 2021.

〓 Research Area : Evolutionary Ecology

Study on evolutionary ecology using insects
All of organisms including agricultural products of material are
product of evolution. All of them are influenced from environmental
and ecological factors. Therefore, understanding of evolutionary
ecological mechanisms is important to consider all living thing. We
are grappling with researches in the mechanism of evolutionary
ecology using mainly insect species. We focus on insect behaviors
including anti-predator behavior, courtship and mating systems,
biological interactions of insect species. Concretely, there are specialized research theme concerning mating system, sexual selection, sperm competition, insect immobility, dispersal tactics, interaction between environments and insect behaviors, using insects.

Research on insect behaviors for applied entomological
techniques〓 Prof.
MIYATAKE Takahisa

28

In addition to the basic researches in evolutionary
ecology, we can apply these results to output concerning applied entomology and insect pest control.
Understanding insect behavior connect to some
applied entomological techniques; for example,
monitoring and detecting the beetles using lights
and/or pheromone in a laboratory and a storehouse,
attraction methods using ultra violet l or blue lights
and lure, or breeding of flightless beetles. In addition
to these researches, we concern some relationships
between native and invasion insects from the world
including common pill bug, sweet potato weevils,
fruit flies, and broad-horned flour beetles.

〓 Research Area : Bioproduction Systems Engineering

Optimization of Sawdust-Based Shiitake Growth with
Cultivation Facility Environments
Shiitake is one of the most popular mushroom in Japan. Dried
one is also famous as a soup stock. The history of cultivation
started more than 100 years ago, logs had been used for fungi
culture. Now a days, logs are replaced with sawdust and they
started to culture in a environmental controlled facility which
may called as a plant factory. Temperature is the most importantfactor, fungi is damaged with high temperature, but not optimized yet. So that we started to optimize environmental factors
for better outputs, not only yield but also quality. Among others,
lighting has a possibility for controlling qualities, such as a size,
shape or color, as shown in right pictures.

Influence of Environmental Conditions on the Chrysanthemum
Leaf Yellow Spot
Chrysanthemum is one of the most popular flowers in Japan. It is
used in various ways, for a funeral, flower arrangement and so on.
In addition there is a demand all year round, so it's cultured in anenvironmental controlled green house. In recent years, yellow spots
appear on the leaf in many species. In chrysanthemums, the stateof a leaf involves commercial values, not only flower quality. The
mechanism how it occurs isn’t still found out clearly and techniques
to prevent it occurring aren’t established. We focused to the environmental conditions as a case. For an objective measurement, a portable image taking device was made, shown in a left picture, and image
processing has been adopted.

〓 Assoc. Prof.
NAMBA Kazuhiko〓 Research Area : Resources Management

Development of Sustainable and Stable Social Systems
in Southeast Asian Countries
In Southeast Asian countries, people's economic activities are becoming more and more active due torapid economic development. Under such circumstances, the demand for land, capital, and labor for agricultural production is changing in rural areas.It is essential
to ensure the sustainable use of resources in the future
through appropriate resource management.We are investigating the current status of agricultural production
activities in such areas and conducting research on thedevelopment of sustainable and stable social systems.
We use selective conjoint analysis, CVM, and othermethods for analysis.Recently, we are also working on
The Interview Survey in Orchards in China
GIS-based analysis.

The Potential for Creating Ethical Value with Agricultural
Production
Ethical consumption is a new trend in which consumers choose businesses and products that are engaged
in solving social issues when they consume.
We are investigating the possibility of creating ethicalvalues by analyzing consumer preferences for agricultural products produced through cooperation between
agriculture and welfare, and environmentally friendly
agricultural products produced in developing countries.

〓 Assoc. Prof.
DATAI Hisashi

The Interview Survey in Organic Pepper
Farms in Vietnam
Graduate School of Environmental and Life Science, Okayama University29

■ Introduction to Research〓 Research Area : Farm Management Systems and Information Processing

Study on Japanese farmer’s management andAgricultural corporative
Generally speaking, Japanese farmers’ scale are smaller than other countries. But, Japanese farmers’ scale
are expanding now. Some rice farmers have more than
100ha paddy field, and some vegetable farmers havemore than 100ha dry field. These farmers are mostly
expanding by lease.
And, these expansion of farm size, farmers’ management need to change. For example, some farmer
need to employ worker, some farmer are forced tochange selling agriculture products. In addition, one
farm corporative had changed to a stock corporation.
We aim to focus on changing agricultural management in Japan.

Study on Japanese agriculture policy and rural policy,
EU, USA, Asia country’s trade policy〓 Assoc. Prof.
OHNAKA Katsutoshi

Why do Japanese farmers change? How do Japanese
farmers change? And, who promotes to change Japanese agriculture management?
The key to solving these questions are “policy”. After
WW2, Japanese government hoped to change Japanese agriculture structure. It promoted to be establishedlarge scale farmers. Imperfectly, Japanese agriculture
structure is changing now. Near the future, many Japanese old farmers will be retired. Therefore, Japanese
government supports large scale farmers for accumulating these old farmers’ farmland by agriculture policy.
Moreover, agriculture policy is effected by trade negotiation.
We are comparing and analyzing other countries’ policy.

〓 Research Area : Mathematical Science for Data Engineering

Mathematical theory of persistent homology
TDA enables us to utilize the mathematical concept of
topology for data analysis, and the research is actively conducted from theory to applications. It does notfollow a unidirectional flow from mathematical theory
to application, and new mathematical problems often
arise from applications. We work on such mathematicalproblems. I already have worked on inverse problem on
persistence diagrams and field choice problem on persistent homology.

Möbius strip and its boundary

Development of HomCloud, data analysis software
based on PH〓 Prof.
OBAYASHI Ippei

In order to connect the theory of persistent homology with applications, data analysis softwareis indispensable. For this reason, we develop “HomCloud”, data analysis software based on PH.
We focus on applications, and practical functionalities such as visualization, machine learning/statistics, and inverse
analysis. HomCloud is
a test platform to see ifmathematical theories
work effectively, and weare implementing ideas
from our research assoon as possible.

HomCloud30〓 Research Area : Applied Mathematics

Commutative Algebra: Theory of integral closure andmultiplicity for modules
My research interests lie in the area of commutative algebra, homological algebra, combinatorics, andcomputational algebra. Among the topics I am particularly interested in are the theory of Buchsbaum-Rim
multiplicity and integral closure for modules, and the ring structure of Rees algebra of modules. These
are general notion of the classical one for ideals and relatively new topics in commutative algebra.
In recent years, I have been working on some basic problems concerning the Buchsbaum-Rim multiplicity and the asymptotic behavior of various invariants such aslength, grade and associated primes associated to multigraded modules.
I am now interested in the theory of integrally closed modules
over a two-dimensional regular local ring, and I am working
on problems about constructing indecomposable integrally
closed modules of higher rank, the theory of Buchsbaum-Rim
coefficient of modules and the ring structure of Rees algebraof integrally closed modules.

Computational Algebra: Applications to mathematicaland data sciences
I am also interested in computational aspects of commutative algebra
and its applications to mathematical and data sciences. Recently, I havelearned a few topics about applied aspects of algebra, especially algebraic statistics, with my students.
I will start to learn these topics and continue to study them with students
towards applications to mathematical and data sciences. Among a
number of topics, I am interested in computing Groebner basis of ideals
and modules systematically appearing in polynomial models in statistics.

〓 Assoc. Prof.
HAYASAKA Futoshi〓 Research Area : Mathematical Analysis of Models

Mathematical analysis of models describing infectious
disease
Propagation of an infectious disease in a population, and the dynamics of density of pathogen invivo are investigated by using mathematical models. Those mathematical models consist of systems of functional equations, such as ordinary differential equations and partial differential equations. For example, in the case of spread of an infectious disease, a susceptible becomes aninfectious by a contact with an infectious, and the numbers of susceptible and infectious agentschange. The numbers as unknown variables satisfy functional equations. If the population is
uniformly mixing, then the equations are ordinary differential equations. If age-structure or spatial
diffusion is considered, then the equations are partial differential equations. We investigate thosemodels in a mathematical point of view, and develop the method of analysis for those models.

〓 Prof.
SASAKI Toru

Graduate School of Environmental and Life Science, Okayama University

31

■ Introduction to Research〓 Research Area : Mathematical Analysis of Models

Study on Zonal Flow Formations in Two-Dimensional
Turbulence on a Rotating Sphere
A two-dimensional incompressible flow on a rotating sphere governed by thetwo-dimensional Navier-Stokes equation is one of the simplest mathematicalmodels for planetary atmospheres. Although this mathematical model is highly
simplified and does not contain many physical processes that may be activelyfunctioning in real atmospheres, the flow field shows rich and interesting phenomena, including a spontaneous formation of large-scale zonal flows. However, these phenomena are the results of very complicated interactions between
many factors, and even the mechanisms of simple and typical flow dynamics are
not necessarily clear. I am especially interested in the emergence and the development of large-scale structures in two-dimensional turbulence on a rotating
sphere, and investigating these by both numerical and analytical methods.

Analysis on Characteristic Features/Structures ofCreatures
Some creatures possess highly unique bodystructures and biological properties. In orderto obtain knowledge and information of essential factors related to the appearance andformation of such characteristic features, I
am performing two different kinds of investigations. One is data analysis of genetic andsome biological data obtained by experiments(collaborative research with an experimentalist), and the other is based on mathematicalmodellings and numerical simulations.

〓 Assoc. Prof.
OBUSE Kiori〓 Research Area : Numerical Analysis of Flow Phenomena

Computational and data science of multiscale/multiphysics complex flow phenomena
Transport and diffusion of dust particles by atmospheric air turbulence andhighly efficient and clean combustion in internal combustion engines arethemes related to environmental problems. These are multiscale/multiphysics complex flow phenomena. To solve these phenomena, a more comprehensive understanding of turbulence physics is important. By developing
reliable and effective methods for direct numerical simulations (DNSs) of theNavier-Stokes equations, performing large-scale DNSs of turbulence using
supercomputers, and conducting data science based on the DNSs, we are
studying turbulence physics related to various complex flow phenomena.
Cluster structure of high vorticity regions in high Reynolds
number turbulence obtained by large-scale DNS

Mathematical and scientific information reduction andvisualization of large-scale time series data

〓 Prof.
ISHIHARA Takashi

A method for efficiently extracting important information from huge timeseries datasets obtained from large-scale numerical simulations is required. Flow visualization and analysis of conditional statistics are effective for understanding turbulence phenomena. Persistent homology
analysis enables us to systematically extract remarkable "changes" inthe spatio-temporal space of a scalar field. By combining these, we aredeveloping methods for detecting and understanding important events incomplex turbulent flow phenomena.
A scalar field and its persistent diagram32

〓 Research Area : Numerical Analysis of Flow Phenomena

Data-driven computing for prediction and control ofwall-bounded turbulenceWall-bounded turbulence significantly contributes to heat transfer and drag on
a wall surface, and the prediction and control of turbulent phenomena leads
to the efficient use of energy, and the time-series data of turbulent flow fields
have been obtained by the numerical simulation. In the future, it is necessary
to develop the data-driven prediction and control technique based on a deep
understanding of the turbulent flow for the wide application in engineering.
We will carry out numerical calculations for various engineering problems andchallenge the turbulent flow problem, which is so-called the final problem ofclassical mechanics, using new techniques of information science such as
The coherent vortical structures in turbulent plane Poiseuille flow.
machine learning in addition to statistical analysis and dynamic system theory. Flow is from left to right. (red) cloclwise, (blue) anti-clockwise vortices.

Data-driven dynamical system for modeling and optimization of nonlinear phenomena〓 Assoc. Prof.
SEKIMOTO Atsushi

We can consider turbulent flow as a vector with a large dimension of freedom and a dynamical system, then we can numerically find invariant solutions such as equilibrium solutions and periodic orbits of Navier‐Stokes equations or turbulence model equations. Understanding the role of invariant
solutions in the turbulent flow phenomenon would provide some insights into the developmentof turbulence models and flow control techniques. The dynamical system approach can also be
applied for the understanding of the mathematical model itself obtained by machine learning
such as deep learning, since it must be common for the phenomenon with strong nonlinearity.
Our research aims are following:development of simulation technique of the complicated process in which we can obtain thedata of real phenomena, such as multiphase flow, chemical reaction, combustion, mixing of various particles, separation and aggregation processes, although the knowledge of macroscopic
or statistical behavior is limited or the detailed simulation is not realistic; and then, development
The stratified homogeneous shear turbulence.
(Red, blue), low and high density fluctuation, (gray) of the technique of optimization and control method which can be applied in a wide range of thevortical structures.
engineering field.

〓 Research Area : Environmental Statistics

Statistical Science for environmental and life science
In modern society, we are required to have grounds forjudgement in various situations. For example, in order tosolve environmental issues, it is important to have calm discussions with showing scientific evidences, without being
influenced by personal feelings.
The statistical science provides the most effective meansof showing such grounds objectively. We wish to contributeto solving issues on environmental and life science throughresearches on statistical science, with making use of computer ability developing drastically.

Statistical modeling and computation for analyzing environmental and epidemiological data

〓 Prof.
SAKAMOTO Wataru

We develop statistical models foranalyzing complicated phenomena that occur in environmental andlife science, such as penalized
spline regression models, mixed
effect models, and Markov random fields, and develop methodsof selecting an optimal model.
The figure shows a graphical model for spatial analysis of disease
mapping data.

Graduate School of Environmental and Life Science, Okayama University

33

■ Introduction to Research〓 Research Area : Environmental Statistics

Statistical data analysis and statistical machine learning
Statistical data analysis and statistical machine learning are indispensable for understanding phenomena in environmental andlife sciences based on data. I am developing those methods andstudying their theoretical properties. Specifically, I am developing
various multivariate analysis methods, including dimension reduction techniques such as clustering and principal component
analysis, for addressing various problems in life sciences.

Functional data analysis for temporally and spatiallydependent data

Functional data analysis isa method that handles measurements as points in a function space, and is one of themain methods for analyzing
data that change continuouslywith respect to time or spatial
position. I am developing
functional data analysis methods and studying their theoretical properties.

〓 Assoc. Prof.
YAMAMOTO Michio〓 Research Area : Design and Analysis of Environmental Survey and Experiments

Visualization of spatio-temporal information andstructural analysis by Echelon tree structure

In recent years, the analysis target of statistical science has become complicated, especially in spatial data, it
is necessary to analyze the data with time series and multi-dimension in addition to usual fixed time and space
situation. Furthermore, the amount number of data has been increasing.
For these complicated and large-scale spatial data, we willdevelop the hierarchically representational approaches basedon "Echelon analysis" by using the geographical and temporal
positional information of each region. The echelon provides a
dendrogram representation of the surface topology of graphtheoretic analysis and surface structure comparison. The
echelon dendrogram is a powerful tool that expresses a unified
framework to handle lattice data with visualization.

Detection of spatial cluster for large scale spatial data

〓 Prof.
KURIHARA Koji
〓 Assoc. Prof.
ISHIOKA Fumio

34

The detection of problems such as the generation status of infective diseases
or hazard maps of natural disasters is very basic and important. Some powerful and useful tools such as geographical information systems (GISs) areavailable, but it is very difficult to determine the location of space-time clusters
for various types of spatial data in large quantities or with large time series.
The aim of this study is to establish methods to identify a disease cluster or a contaminant
cluster, so-called hotspot, forvarious kinds of spatio-temporal spatial data and to develop
software for that.

〓 Research Area : Design and Analysis of Environmental Survey and Experiments

Some applications in multivariate methods withalternating least squares
In recent years, we can obtain a huge data which have quantitative and qualitative variable. We
call this type of data as mixed measurement levels data. The alternating least squares (ALS)
algorithm is a most popular iterative computational method for mixed measurement levels data.
The ALS algorithm alternates between the optimal scaling step and the parameter estimation
step. The optimal scaling step is to obtain optimal scaled data by quantifying nominal and ordinal scaled data. The parameter estimation step is to compute parameters for the optimal scaled
data. However, the drawback of the ALS algorithm is that its convergence is linear and very slow
for very large data with mixed measurement levels.

〓 Prof.
IIZUKA Masaya

In order to circumvent the problem ofslow convergence of the ALS algorithm,
we provide an acceleration algorithm.
The algorithm converges faster than theoriginal sequence of ALS iterations.

〓 Research Area : Environmental Epidemiology

Quantitative assessment of the effects of environmental pollution on the humans
In recent years, the human health effects of environmental pollution are an important concern
for society. The main types of environmental exposures that affect human health are physical,
chemical, biological, psychological, social, and cultural exposures. However, the actual scientific methods for clarifying these effects and the institutions that compile the results are not wellknown to the public. Moreover, because this is not known, many media and people do not know
how to read the results of newstudies, let alone benefit fromthem. They also don't know how
the results are incorporated intosocial and legal systems. In otherwords, the scientific knowledge ofhuman impact is not well utilizedin Japan. We are researching thepromotion of scientific literacy
on the environment and humanhealth effects.

〓 Prof.
TSUDA Toshihide

Assessment of the effects of biological exposures onhumansIn the case of biological exposures, bacterial and viral exposures are the representatives of human health effects of the environment. Currently, a new coronavirus is causing a pandemic in theworld. The transmission of new coronaviruses is thought to be through respiration and throughcontact. Along with this, food poisoning through food and drink is the most common form of bacterial and viral exposure. We are conducting research to collect these cases and study them,including legal developments, for future prevention.

Graduate School of Environmental and Life Science, Okayama University

35

■ Introduction to Research〓 Research Area : Solid Waste Management and Recycling
Regional waste material recycling towards low carbon
society: Sanitary waste treatment is a fundamental in solid waste management, moreover, it is required that “fromwaste to material” and “from waste to energy” to mitigate
green house gases emission. Solid waste processes, suchas waste separation at source, segregated waste collection,
optimal waste transportation, material and energy recovery
treatment, and safe landfill disposal, should be combined
appropriately so as to shorten the environmental burden.
Our laboratory studies on designing methods to establish asophisticated solid waste management that is suitable forsustainable regional society, specially in Asia.

(Mixing kinds of biomass waste forcomposting)〓 Prof.
FUJIWARA Takeshi(Waste characterization tests inOkayama city)

Evaluation of the biomass waste recycling in university
campus: From view point of carbon neutral, biomass waste
should be more utilized in a sound material-cycle society. By
considering characteristics of various kinds of solid waste generated in our campus, such as kitchen waste, mowed grass,dead leaves, pruned branches, agriculture waste, animal dung
in different seasons, our laboratory researches on effective
biomass waste recycling methods.

Development of a disaster waste management training
system: Japan is exposed by many risks of natural disasters
such as earthquake, land sliding, tsunami, flooding and so on.
Once a big natural disaster comes like the Great East Japan
Earthquake, a huge amount of disaster waste generates in ashort period. In order to recover the town from the damage
speedy, initial countermeasure actions for disaster waste treatment by local government are quite important. Therefore, ourlaboratory is constructing a knowledge base of the actions andalso developing a training support system for the local government.

(Disaster waste in Iwate prefecture)〓 Research Area : Solid Waste Management and Recycling

Modeling on waste generation and discharge

To support rational and effective decision making onmunicipal solid waste management toward sustainable
society, our laboratory aims to accumulate the scientific base by the following research activities:✓ Detail survey on municipal solid waste generation,
demographics, 3R behavior, pro-environmental
attitudes, lifestyle, and household expenditure in
Japan and Vietnam✓ Exploring influence factors and Bayesian modelingof waste generation and 3R behavior✓ Political effect prediction on 3Rs and reliability verification✓ Accuracy improvement on sales prediction of fooditems by Deep Learning toward food loss reduction

Conceptual framework on relationships between 3R
promotion measures and 3R behavior

Actual daily sales variation of rice balls andPredicted sales amount by deep learning

Behavior modification on 3Rs〓 Assoc. Prof.
MATSUI Yasuhiro

To establish and expand 3R good practices towardsustainable society, our laboratory tries some pilot
studies including 3R promotion and effect measurement as the following activities:✓ Experience-based activity for 3Rs in cooperation
with trial dining event in downtown by gamification
Experience-based 3R promotion✓ Development of beverage by returnable bottle with
Carbon Footprint Ecolabel
To enhance the citizens understanding on the effectof Reuse, the label indicated “When you discard inone, you discharge 430g-CO2e. When you reuse
Flyer of the carbonated
Ecolabel instruction on GHG
5 times, you discharge 130g-CO2e in one which
drink provided
mitigation effect by repeatedmeans you can decrease 69% of GHGs.
by returnable bottle

36

use of returnable bottle〓 Research Area : Solid Waste Management and Recycling

Study on anthropogenic mercury releases for the evaluationof the effectiveness of the Minamata Convention on Mercury
The combination of anthropogenic activities and long-term atmospheric transport
has resulted in a sustained increase in global mercury concentrations in air, inwater and on land. The Minamata Convention on Mercury (MCM), is a global treaty
with the goal of protecting human health and the environment from anthropogenic
releases of mercury. This study aimed to quantify the mercury inputs and outputs
in China in 2016–2019 according to source category and investigate the effect of
scenario/technology transformation required by the MCM on the subsequent distribution of mercury among environmental and intermediate reservoirs. This is thefirst attempt to provide a systematic evaluation of the validity of the MCM. As the
MCM moves into the implementation phase, further information from scientific dataand studies is critically needed to support decision-making and management. The
results of this study can provide such information, facilitating the creation of strategic management policies for mercury as the MCM is implemented.

Feasibility Study of Biomass Waste Recycling System
in University Campus〓 Asst. Prof.
HABUER

Okayama University has an expansive campus in Japan and generates much biomass that is usually disposed of byoutsourcing waste treatment to private companies. The university
should tackle reducing and recycling waste within the campus asa regional society member to establish a sound material-cycle society. We evaluated the potential to recycle the biomass waste on
the campus by first measuring or estimating the amount of biomass
waste generated almost through a year. Secondly, we conductedfeasibility studies such as analysis of methane gas and compost
production, power consumption, and CO2 emission of a methane
fermentation facility and a composting facility.
Biomass Recycling Facility Process Flowin Campus〓 Research Area : Environmental Measurement and Control

Assessing the fate of chemicals in the environment
and engineered processes
Concentration changes and dynamics of environmental
chemicals are predicted and evaluated based on partition
equilibrium properties of chemical compounds and theirconversion/degradation kinetics. The target compounds areorganohalogen compounds, PAHs, and other emerging pollutants. The target engineering processes include water treatment and gas cleaning, and solid/liquid waste treatment insuch environmental media as water, air, soil, and sediment.

Safe and appropriate disposal treatment of waste water, flue gas, and solid/liquid
waste, and developing further technology for recovering materials/energy from waste
Various exhausts, such as wastewater, flue gas, andother anthropogenic waste emissions should be appropriately and safely disposed. Currently, material andenergy recovery is highly desired in the context of establishing a sound material recycling society.

〓 Prof.
KAWAMOTO Katsuya

Because energy recovery from waste treatment plays a
key role in eliminating fossil fuel use and GHG emissions,research and development corresponding to the type andproperties of waste are performed. Safety assessments ofthe systems are also conducted.
Graduate School of Environmental and Life Science, Okayama University

37

■ Introduction to Research〓 Research Area : Urban and Transport PlanningResearch on the realization of walkable cities
In order to realize walkable cities, various
studies are required to make it easier for
people to walk, such as improving public
transportation and traffic calming. In this research, we will study the design of an easyto-walk space that supports daily life such as
children and the elderly, mainly focusing on
living roads. Specifically, road space designin which automobiles running speed are unconsciously controled, and space design inwhich children in the process of growth canunconsciously take safe actions.

Research on public transportation in depopulated areas
In this study, we will evaluate the impact of
the existence of public transportation on the
consciousness of living in depopulated areas,
the role played by the area in order to maintain public transportation, and measures toimprove sustainability through mixed cargoand passengers.

〓 Prof.
HASHIMOTO Seiji〓 Research Area : Urban and Transport Planning

Historical studies in civil engineering, disasterrecovery and urban formation
It is important to look back on the history in order to develop the town in the future. What kind ofcivil engineering technology did the predecessors develop, how did they recover after the disaster, and how did they build the city? We reveal their history by collecting and analyzing archives(documents, drawings, oral histories).

Preservation and utilization of historical civil engineering structures
If not rescued, historical civil engineering structures will be lost. We will conduct a survey andevaluate the value of these in order to promote their preservation and utilization, and to utilize
them as a "regional asset" in regional development. Then, we will consider and implement ways
to preserve and utilize the civil engineering heritages.

〓 Assoc. Prof.
HIGUCHI Teruhisa

38〓 Research Area : Urban and Transport Planning

Developing a road map for urban planning adapting to
declining population
1) This study elucidates the status
and issues of change in land use
during a period of declining population.
2) Based on quantitative evidence,a road map for urban planning
adapted to a declining population
is developed as a step toward realizing an urban structure with low
environmental load.

Identifying an urban structure model for Eco-livable
cities〓 Assoc. Prof.
UJIHARA Takehito

A low-carbon, environmentally-friendly lifestyle often has thenegative reputation of introducing limitations and burdens into
our daily lives. However, reviewing global success cases inurban planning shows that many of these cities are actually
low-carbon and livable (Eco-livable cities). Even more interestingly, many of these cities have used past serious environmental issues as an opportunity to achieve their ideal urban
vision over several decades.
This research (1) identifies an urban structural model for“eco-livable cities” that simultaneously achieve low-carbon
and livability, and (2) constructs a planning theory to achieve
this through a survey and analysis of Japanese and international regional cities as case studies.

〓 Research Area : Water Environment and Sanitation

Wastewater to food production ~ a new wastewater
treatment process with resource recovery
We are working on wastewater treatment process that is economically beneficial, andresources in wastewater are recovered and recycled for sustainable food production.
Fertilizer including phosphorus is necessary to produce food. The demand of the fertilizer
has been increasing to supply food for increasing population. However, fertilizer reserveis limited, and its production causes environmental pollution. To protect the environmentand supply enough food for our children, we have been developing a new wastewater
treatment process not only to treat the wastewater but also recover nutrients for fertilizer.
More than that, we have been trying to increase the “value” of the recovered products
using microalgae. This microalgae produces carotenoids such as b-carotene and astaxanthin, those are high value antioxidative pigments and are dealt with at a high price.
The production of the pigment is the economical driving force of recovering nutrients fromwastewater, finally to establish the sustainable food production.

Understanding of chemical and biological reaction
mechanisms by computer simulation〓 Prof.
NAGARE Hideaki

Computer simulation is a powerful tool to understand the mechanism of reactions
such as degradation of pollutants in water treatment process, and oxidation reactions in microbial cell. Using the computer skills and the knowledge of physicalchemistry including thermodynamics, we have been doing the simulation researches. One of the example is the degradation of ionic liquid with ozone. From
which chemical bond does the degradation reaction occur? The simulation gives
us the insight of the reactions.

Graduate School of Environmental and Life Science, Okayama University

39

■ Introduction to Research〓 Research Area : Water Environment and Sanitation

Evaluation of the groundwater function for conservation of coastal ecosystems
Seagrass and seaweed meadows are regarded as an important
coastal ecosystems for their functions of “ecosystem service”,
such as carbon stock and habitats. Though conservation ofthese meadows is a global issue for the healthy cycles of foodand materials, their biomass has been decreasing worldwide. Diversity in the coastal environment (e.g. variation in salinity, watertemperature, nutrients, bottom materials etc.), produced by bothsea-factors and terrestrial-factors, is important for seagrass andseaweed meadows to coexist with the other primary producers.
We evaluate the function of “submarine groundwater discharge(SGD)” for diversity production in the coastal environment byPotential diversity-creating factors in the coastal
field observations, satellite data, and hydrological models.
environment

Human and climate impacts on water environment and water
resources〓 Assoc. Prof.
SAITO Mitsuyo

Human activities in urban and rural areas alter the natural hydrologic and material cycles in watersheds. For example, overdrawing
groundwater for drinking, irrigation, and industrial use increase the risks of water deficiency, land subsidence, contamination andsalinization.
Increase of nutrients (e.g. nitrogen, phosphorus) entering the environment by human activities(e.g. agriculture, industries) cause
eutrophication of surface water environments and contamination ofgroundwater resources.
We evaluate the current status and future outlook of water resourcesand environments based on field observations, chemical and isotopic
analysis, and hydrological models for several countries in different
climate zones, urbanization status, and cultures. We will also suggest
Land subsidence (left) and surface water pollution (right)
the solutions for sustainable water-nutrient cycles for the future.
in Jakarta metropolitan area, Indonesia〓 Research Area : Ceramic Materials

Effect of acid treatment conditions on the dissolution behavior of
constituent elements in molten slags and ashes of municipal waste
In municipal waste molten slags, valuable elements such as Si,
P and Ti are present. Our research group has developed a newrecycling method in which P and Ti-containing SiO2-rich solid
phase is recovered after acid treatment of B2O3-added molten
slag glasses. We also found that the SiO2 phase is formedby dissolution reprecipitation process. It is hence expectedthat by changing treatment conditions, selective recovery of a
specified element will be realized. Then, in this project, we areinvestigating elution behavior of constituent elements in molten
slags and ashes of municipal waste by changing basicity ofslag glass, where an alkali oxide was added to the molten slag
to prepare slag glasses having different basicities.

Recovered solid after acid treatment[DOI: 10.1016/j.jascer.2013.03.003]

Development of novel glasses for immobilization of radioactive iodine〓 Prof.
NANBA Tokuro〓 Assoc. Prof.
BENINO Yasuhiko40

TRU (TRans-Uranic) waste contains radionuclides such as Iodine-129. Iodine-129 has extremely long half-life of 15.7 million
years, and hence it is a key nuclide at the safety assessment
for the geological disposal of TRU waste. However, it has highvolatility so that the conventional vitrification technique is notapplicable. Then, new iodine-129 immobilization technique
is required. A lead borate glass with low melting temperature
is a candidate for the vitrification technique. In our researchgroup, structure (atomic arrangement) of the iodine-containing
lead borate glasses has been studied by using combination of
Structure model of lead borate glass
experiments and computer simulations to clarify the relation beand Iodine-containing vitrified waste[DOI: 10.1016/j.pnucene.2016.05.008] tween glass structure and iodine immobilization property.

〓 Research Area : Inorganic Functional Material Chemistry

Development of new environmental purification materials based on inorganic layered materials
Water purification is one of the important issues of the presentday. Although TiO2 is the most prevalent and practical photocatalyst for elimination of hardly decomposable organic materials, both improvement of an affinity with target materials anddevelopment of decomposition performance under visible lightare required for TiO2 materials. One of the solution methods ofthe former is hybridization of TiO2 and an inorganic layered material. With this hybridization, the synergy effect of layered material and TiO2 can improve the decomposition performance oforganic materials. In this research, we will develop an environmental purification system with high efficiency and ecofriendly
by preparing hybrids of various metal oxide semiconductors
and inorganic layered materials.

Development of solid oxide fuel cells (SOFCs) for various types of fuels〓 Prof.
KAMESHIMA Yoshikazu

Solid oxide fuel cells are a class of fuel cells characterized
by the use of a solid oxide material (ceramic material) as theelectrolyte. SOFCs use a solid oxide electrolyte to conduct
negative oxygen ions from the cathode to the anode. The
electrochemical oxidation of the hydrogen, carbon monoxide
or other organic intermediates by oxygen ions thus occurs on
the anode side. In this research, we will develop new anodematerials that are compatible with the supply of methane andother organic intermediate fuels.

〓 Research Area : Inorganic Functional Material Chemistry

Study on photocatalytic self-cleaning surfaces
Wettability of solid surface is interesting.
Also it is important for our daily life. Titanium dioxide (TiO2) surface shows super-hydrophilicity (water contact angle
less than 5 degree) by the irradiation ofultra violet light. TiO2-coated materials
such as glasses and tiles of buildings
have been widely used as self-cleaningmaterials. Recently, we focus on niobium oxide-based photocatalyst as highfunctional self-cleaning material. We
are trying to develop next environmentally friendly self-cleaning coatings.

Study on underwater super-oleophobic surfaces〓 Assoc. Prof.
NISHIMOTO Shunsuke

Oil wettability of solid is an important physicalproperty of the materials. We have developing functional materials with underwatersuper-oleophobic surface (oil contact angle
larger than 150 degree). underwater super-oleophobic mesh can be applicable as aspeedy oil-water separation filter. Recently,
we succeeded to develop TiO2 photocatalyst
oil-water separation filter. Moreover, we are
currently investigating calcium-based materials as oil-water separation filter.

Graduate School of Environmental and Life Science, Okayama University

41

■ Introduction to Research〓 Research Area : Advanced Organic Materials

Physical modification of carbon nanotubes with a dendrimer bearing
terminal mercaptoundecahydrododecaborates (Na2B12H11S)
The functionalization of dodecaborates has attracted much attention, both for the development of boron neutron capture therapy(BNCT),where 10B nuclei capture thermal neutrons to emit 7Li nuclei and alpha particles that destroy cancer cells. Increasing focus has
been placed on the conjugation of the thiol‐substituted B12‐cluster mercaptoundecahydro‐closo‐dodecaborate (Na2[B12H11SH]; BSH). Thisis mostly due to the fact that BSH offers great biological advantages, which includes higher boron
content, ionic nature, higher solubility in water, significantly lower toxicity based on its boron content,
and its clinical use in the treatment of cancer (BNCT). For a boron delivery agent to be successful in
BNCT, both high tumor‐targeting selectivity and the possibility for in vivo imaging are required. However, reports on the conjugation of BSH with bioimaging agents remain scarce. We have successfully
synthesized a new water‐soluble dendrimer that bears B12‐cluster terminals, with potential applicationsin BNCT. Moreover, the physical modification of SWCNTs with boron-cluster dendrimer furnished
SWCNT/(boron-cluster dendrimer) nanohybrids that exhibit NIR‐I‐to‐NIR‐II fluorescence. Further investigations into the cellular uptake and cytotoxicity of our materials are currently in progress.

Disproportionation-induced solid-state fluorescence in
6,13-dihydropentacenes〓 Sr. Asst. Prof.
TAJIMA Tomoyuki

The molecular design of π-conjugated systems is crucial for the development of new functional materials. Nevertheless,reports on π-conjugated systems exhibiting disproportionation-induced photoluminescence changes are relatively rare.
Against this background, we decided to explore the utility of disproportionation reactions for the development of fluorescent chromic materials. The thermally and photolytically induced disproportionation of 6,13-dihydropentacene derivatives
into tetrahydropentacenes and pentacenes results in unique solid-state fluorescence. The fluorescence thereby depends on the molecular structure and themolecular arrangement in the solid state. The molecular structure and conformation in the crystals strongly influence the disproportionation reaction. Upon
heating or photoirradiation of 6,13-dihydropentacene derivatives in the solidstate, the fluorescence color gradually changed from bright blue to red. The solid-state fluorescence behavior induced by disproportionation may serve as an
example for guided molecular engineering, providing fascinating possibilities totune materials for sensing, as well as optical and thermal recording applications.

〓 Research Area : Environmental Polymer Chemistry

Creation of environmentally benign polymerization system and polymer materials
Aromatic polymers are used in various industrial fields
as high-performance materials due to their excellent
properties, such as thermal stability, mechanical properties, or chemical stability. However, processing of thesepolymers is extremely difficult because of their intractability. We have been studied the unique polymerization
system for morphology control of aromatic polymers.
As a result, we obtained various morphologies such as
whisker, ribbon, helical, sphere with dimple, and so on.
This polymerization system and materials are one of theanswer towards sustainable development of society.

Studies on biodegradable polymers with unique topology based on crystallization control〓 Prof.
KIMURA Kunio〓 Assoc. Prof.
YAMAZAKI Shinichi〓 Asst. Prof.
ATARASHI Hironori
42

This study conducts the development of high-performance biodegradable polymers with the tunability of physical properties such as mechanical strength and thermal resistance using the uniquetopology of cyclic homopolymer and topological blend polymer having cyclic polymer as a component. The cyclic homopolymer and topological blend polymer are capable of control of crystalline
and entanglement state. The unique morphology and crystallization behavior have been clarified.

〓 Research Area : Environmental Process Engineering

Study on proposing some environmental-friendly
chemical processes
In order to convert an unusable material to a valuable
material, we research to propose an environmental-friendly chemical processes. We proposed the threechemical processes shown in the figure to produce a
monomer to make a bioplastic from woody biomass. As
the first process, we used subcritical water to hydolyze
cellulose and hemicellulose. We converted monosaccharide to 2,5-Hydroxymethylfrufral (HMF) by the quick
extraction as called as “Slug Flow” as the second process. We proposed a converting chemical process using a metal catalyst with liposome, which is an artificial
cell membrane, to produce 2,5-frandicarboxylic acid.

Study on a mechanism of transport phenomena
between immiscible organic-water phases in Slug Flow
As mentioned above, the quick extraction is effective to
produce HMF. The key factor is transport phenomena
between immiscible organic-water phases in Slug Flow.
We try to elucidate what is an important factor for thetransport. The depth of the interface is one candidate toeffect the transporting rate of HMF. The depth depends
on variety of organic solvent. We also research the effectof surfactants on the depth of the interface.

〓 Prof.
KIMURA Yukitaka〓 Research Area : Environmental Reaction Engineering

Research on waste recycling for building a recycling-oriented society, andbiomass and green hydrocarbon cycles for global environmental issues
We aim to solve environmental problems with a chemicalengineering (reaction engineering) approach, focusing onfour fields: building a recycling-based society, global environmental problems, environmental conservation, andbasic reaction engineering technology. We are conducting
research mainly focusing on waste recycling for building a
recycling-oriented society, researching biomass and greenhydrocarbon cycles for global environmental issues, developing environmentally friendly adsorbents and catalysts
effective for air, groundwater and soil pollutions protection
technologies.

Research on recycling of valuable components in pulverized
waste silicon-based solar cells by flotation separation method〓 Prof.
UDDIN Md. Azhar〓 Prof.
(Special appointment)
KATO Yoshiei

Flotation separation has been widely applied in the mining
industry to concentrate valuable elements in a raw mineral
for many years. The multiple components with the differencein surface property such as hydrophobicity and hydrophilicity
are efficiently separated by the gas bubble and surfactant.
As recent development for a recycling process, we are investigating the study on collecting a high purity of valuable
elements in pulverized scraped silicon-based waste solar
cells by flotation. A chemical engineering approach is taken
to this study and the goal is put to practical use.

Graduate School of Environmental and Life Science, Okayama University

43

■ Introduction to Research

Division of Agricultural and Life Science〓 Research Area : Applied Natural Product Chemistry

Investigation of inhibition mechanism of sialidase of influenza virus anddevelopment of novel inhibitors: difluorosialic acid and sulfo-sialic acid
Development of improved influenza sialidase inhibitors is critical to prepare for potential influenza pandemics. Based on the hypothesis that Tyr406 forms an acetal intermediate in the catalytic
cycle of sialidase, we synthesized 2a,3a-difluorosialic acid (1) as a suitable probe to test if a covalent intermediate can be captured. As expected, X-ray crystallographic analysis revealed that
1 forms a covalent complex with Tyr406 of influenza silalidase. This indicated that Tyr406 attacks
from the b-face of the substrate, leading to hydrolysis with retention (inversion and inversion) of
the configuration. In addition, 1 possessed potent anti-influenza activity (including that of Tamiflu
resistant virus) with IC50 inhibitory constants of 10 to 1000 nm, providing the first proof-of-concept
for mechanism-based influenza sialidase inhibition.
In addition, a next-generation inhibitor, sulfo-sialic acid (2), was developed. The sialidase inhibitory activity of 2 was more potent than the corresponding carboxy and phosphono derivatives,presumably due to stronger attraction to the triarginyl binding site of the enzyme.

〓 Prof.
KIYOTA Hiromasa

NaturalPolymer
ProductChemistry
Chemistry〓 Research Area : Applied
Environmental

Solid-Supported Combinatorial and Parallel Synthesis
of Bioactive Compound Libraries.
The solid-phase strategy is a strong tool for high throughput synthesis and combinatorial chemistry. Synthetic intermediates are retained on the support and can be, therefore, quickly separated
from the reaction mixture without extraction, concentration, and purification steps. Solid-phase
synthesis is thus particularly advantageous
for multi-step iterative synthesis. Various
solid-phase automated synthesizers havebeen developed and are now commerciallyavailable. Our research focus on automatedsynthesis of bioactive compound and building-up of compound libraries by automaticsynthesizer Nautilus 2400.

Chemo-Enzymatic Synthesis of glycosides andglycoconjugate.

〓 Assoc. Prof.
IZUMI Minoru

44

Galactofuranose is a component of polysaccharides and glycoconjugates. There are few reports
about the involvement of galactofuranosyltransferases and galactofuranosidases in the synthesis
and degradation of galactofuranose-containing glycans. The cell walls of filamentous fungi in thegenus Aspergillus include galactofuranose-containing polysaccharides and glycoconjugates, suchas O-glycans, N-glycans, and fungal-type galactomannan, which are important for cell wall integrity. Our research interests focus on many problems that lie at the integrity of cell wall, we are especially investigating themethodology to synthesize glycosides and glycoconjugates by chemo-enzymatic methods including
use of some enzyme.

〓 Research Area : Chemistry of Bioactive Compounds
Aiming for use in medicine and agrochemicals, we are conducting
1: Search for natural bioactive compounds (highly functional compounds)
2: Research on biocatalyst-mediated conversion of low-functional substances.

Search and use of new enzymes effective for production of useful substances(1) We can synthesize various dehydrogenated cyclic dipeptides by using the novel cyclic dipeptideoxidase that we found in actinomycetes. We are investigating various properties of this unique
enzyme and conducting applied research on highly sensitive
detection of cyclic dipeptide and production of dehydrogenatedcyclic dipeptide using this enzyme.
(2) We are preparing new antioxidant active substances by enzymatic conversion from olive secondary metabolites, and are
studying their usage.
(3) We are conducting a detailed study of microbial enzymes
that show characteristic transglycosylation activity.
(4) We are studying methods for treating woody biomass with

Search for chitinolytic enzyme inhibitors and analysisof their bioactivity〓 Prof.
KANZAKI Hiroshi〓 Prof.
NITODA Teruhiko

The epidermis of insects and the cell wall of filamentous fungi contain the polysaccharide chitin. Since themetabolism of chitin is essential for the growth of insects andfilamentous fungi, the enzymes responsible for the metabolismof chitinase and β-N-acetylglucosaminidase are expected to be
applied to pest control agents and antibacterial agents. We haveconducted research to find inhibitors of these enzymes in microbial metabolites. We have discovered two novel β-N-acetylglucosaminidase (GlcNAcase) inhibitors with distinct specificity.
We are trying to elucidate the molecular basis of their inhibitory
specificity and to search further novel GlcNAcase inhibitors.

〓 Research Area : Functional Glycobiochemistry

Functional analysis of oligosaccharides involved inplant differentiation, growth, and fruit maturation
In developing hypocotyls, seeds, and fruits at the maturing stage, free N-glycans (FNG) released from glycoproteins or glycopeptides occur at micro molar concentration. We analyze (1) the biofunctions of FNs involvedin plant differentiation, growth, and fruit maturation, (2)chaperon-like functions involved in the protein-foldingor -refolding mechanism. Based on the unraveled of the
biofunctions of FNGs, we aim to establish a new plantbiotechnology to control plant differentiation, growth,and fruit-maturation through artificial regulation of theexpression of glycogenes (glycosidases, glycosyltrasferases, and glycan-liberating enzymes).

Analysis of in vivo / in vitro functions of free N-glycans (FNGs)
responsible for correct protein folding and refolding〓 Prof.
KIMURA Yoshinobu

In plant and animal cells or tissues, the liberated asparagine-linked glycans (free N-glycans, FNG) ubiquitously occur. Recently we have found that these
FNGs induce the correct protein folding or refoldingof denatured or misfolded proteins at millimolar concentration. We analyze the chaperon-like activity of
FNGs involved in the protein quality control system
working in eukaryotic cells using biochemical andphysiochemical strategies. We aim to establish a newconcept of glycan function responsible for correct
protein folding and apply the chaperon-like function
to the development of glycol-reagents stimulating thecorrect construction of protein 3D structures.

Graduate School of Environmental and Life Science, Okayama University

45

■ Introduction to Research〓 Research Area : Functional Glycobiochemistry

Analysis of the immunological activities of antigenic
glycans of plant or insect origin
In many case, allergens of plant or insect origin are
glycoproteins to which antigenic glycans are linked
and these allergens are often referred as glycoallergens. We analyze the chemical structures and immunological activities of these plant glycoallergens.
Recently, we have found that plant antigenic glycans
suppress the production of Th2 type cytokine, IL4, from Th2 immune cells. For the application of
immunological activity of these plant glycans to thedevelopment of glycodrugs, we analyze their cellularimmunological activities and synthesize neo-glycopolymers carrying the immunoactive glycans.

Application of a neo-glycopolymer carrying multivalentN-glycopeptides for identification of nucleocytoplasmic lectins
Recently, several novel plant lectins localized in the nucleus and/or cytoplasm of plant cells have been reported,and some of them have induced the gene expression
under biotic and/or abiotic stress condition. The endogenous ligands and the physiological role of these carbohydrate-binding proteins have not been identified to date.
We have synthesized glycopolymers carrying multivalentN-glycopeptides to identify and characterize the nucleocytoplasmic lectins.

〓 Assoc. Prof.
MAEDA Megumi〓 Research Area : Applied Enzyme Chemistry

Understanding of molecular mechanisms of biomineralization
Biominerals are minerals formed by organisms. They possess various superior material properties derived from their structure and composition. Understanding biomineralization could contribute to the development of material science and nanotechnology. We are studying biomineralization using omics technologies.

Magnetite biomineralization in chitons

The denticle caps of chiton radular teeth consist of magnetite. The elucidation of magnetite biomineralization mechanisms in chitons could pave theway for developing novel environmentally benign processes for the production of iron oxide materials. To clarify the molecular mechanisms of magnetite biomineralization, we constructed de novo assembled transcriptome
data from radular tissue of chitons for the first time. Furthermore, we identified the proteins that were specifically expressed in the mineralized teeth.
Characterization of these proteins using genetic engineering techniques are
ongoing.

Silica biomineralization in diatoms〓 Asst. Prof.
NEMOTO Michiko46

The beautiful geometric design of diatom silica cell walls
have attracted many people over the years. Recently, it has
been shown that diatom silica cell walls are not only beautiful
but also useful in the nanotechnology field because of their
many exceptional material properties. We are studying silica
biomineralization in consideration of future nanotechnological applications.

〓 Research Area : Food Biochemistry

Activation of endogenous defense mechanisms by foodconstituents and their metabolites by gut microbiota
Electrophilic substances in foods possess potential to exhibit various biological activities throughtranscriptional regulation of cytoprotective genes involved in cellular defense against biotic
stresses induced by xenobiotics, reactive oxygen species, and alcohol. We have been focusing
on food-derived electrophiles such as isothiocyanates, flavonoids, and phenolic acid metabolites
of quercetin 4´-glucoside, the major polyphenol in onion. Modulating effects of these compounds
on cytoprotective gene expression and the underlying molecular mechanisms are investigated by
the forward chemical genetics approach to elucidate their physiological significance.

〓 Prof.
NAKAMURA Yoshimasa〓 Research Area : Chemistry of Bio-signaling

Study on the molecular mechanisms that regulate
environmental stress responses in plants
In nature, plants are exposed to a combination of a wide variety of environmental stresses. To
sustain their growth, plants have developed robust mechanisms that integrate the stress signals
and then output the optimal adaptation response. The long-term goal of our research is to uncover the molecular mechanisms of how plants achieve the signal integration and its conversion
to the downstream response. In particular, our research focuses on stress signaling regulating
stomatal movement. Stomatal pores, which are formed by pairs of guard cells in the epidermis
especially of leaves, regulate gas exchange for photosynthesis and transpirational water loss.
Guard cells can perceive various stimuli such as light, CO2, pathogen infection, and various phytohormones such as abscisic acid, jasmonate, and salicylic acid, then transducing the inputs toa change in stomatal aperture. Using multidisciplinary approaches, we aim to reveal the detailed
mechanisms of signaling cascading from stress sensing to stomatal aperture regulation in guard
cells. We also study the basic mechanisms of heavy metal and salt stress responses in plants
using model plants as well as cultured cells. Our research advance will contribute to develop
new technologies that improve crop productivity and safety.

〓 Prof.
MURATA Yoshiyuki

Graduate School of Environmental and Life Science, Okayama University47

■ Introduction to Research〓 Research Area : Microbial Function

Frontiers of Nucleoside Antibiotics with Antifungal,
Antiviral, and Antitrypanose Activities.
Nucleoside antibiotics comprise a group of microbial products, which has antifungal, antiviral and anti-protozoan activities. These antibiotics,
mostly produced by Streptomycetes species as their secondary metabolites, can inhibit parasite-specific processes such as viral proliferationand protozoan-specific metabolism. Despite the potential utility and yet increasing demands
for such powerful antibiotics, there are few successful utilization case of antiviral and anti-parasitic activity of the nucleoside antibiotics, due exclusively to the poor production yield and the
difficulty in identifying the biosynthetic genes in the genome of the producer strains. The present
research aims to develop an alternative strategy for production improvement by modifying thecellular machineries for transcription and translation to increase and maintain the biosynthetic enzymes without the need of cloning the biosynthetic
genes. RNA polymerase genes and ribosomal genes are altered on the
Nucleoside antibiotic producing strain
genome to increase and maintain the biosynthetic genes.
Streptomyces incarnatus NRRL8087.

Engineering RNA polymerase based on Molecular Dynamics Simulation and Density
Function Theory Calculation - QM/MM Estimation and Experimental Proof.

〓 Prof.
TAMURA Takashi

Computation of RNA polymerase
to improve the transcription rate.

RNA polymerase (RNAP) has four conserved residues, which
are collectively termed as rif-1 cluster residues, in the β-subunit.
Alteration of the rif-1 residues by site-directed mutation very
often results in production enhancement of the secondary metabolites. The residues are positioned to interact with the newly
synthesized mRNA, and they can regulate the polymerization
rate. Multiple combination of mutation can alter the interaction
between the β-subunit and RNA chain, which is also computed
by MD-modeling and Density Function Theory calculation. Computation gives the theoretical consequence of residue change
in terms of interaction energy at the electronic levels, and experimental data gives clues on the most appropriate interaction forthe highly enhanced production of the secondary metabolite .

〓 Research Area : Plant Genetics and Physiology

Photosynthesis and chloroplast biogenesis:
Understanding to innovation
Plants perform photosynthesis in chloroplasts, where light energy is converted into chemical energy by a series of electrochemical reactions. In contrast, sessile land plants are exposed
incessantly to excess light energy or harsh atmospheric environments that engender ‘photodamage’. How do plants cope withsuch photosynthetic inactivation? What are the key elements tomaintaining or even maximizing chloroplast functions?
Our group studies various aspects of chloroplast development and photosynthesis. Through understanding of the factors involved in photoprotection and chloroplast function, we aim at improving crop productivity
against atmospheric stress over the long term.

Ongoing projects in Plant Light Acclimation Research Group
1. Proteolytic machineries in chloroplasts

2. Photooxidative stress and quality control of photosynthetic proteins
3. Maintenance of chloroplast envelope through protection
mechanism through VIPP1〓 Prof.
SAKAMOTO Wataru〓 Asst. Prof.
OKEGAWA Yuki

48

4. Behavior of chloroplast DNAs during leaf maturation andsenescence
5. Quantitative trait locus (QTL) controlling stay green insorghum〓 Research Area : Plant Genetics and Physiology

Dissection of the mechanism to determine starch grain morphology
and Breeding new varieties with novel starch properties
Starch is a glucose polymer which plants synthesize as a photosynthetic product and is human energy source as a staple food. In addition,

starch is used as food additives and industrial

products (adhesives, printing improvers). Starchis synthesized as particles, so called “starchgrains (SGs)” in plant cells.

The shape of SGs shows variations depending on plants species and limits the production

efficiency and functionality of starch. However,details of the shape determination mechanismof SGs are not known. To understand the mechanism and to create new SGs with novel properties, I am now screening and analyzing rice andComparison of SGs of rice andbarley. Endosperm sections arestained with iodine to visualize SGs.

barley mutants defective in SG shapes.

In addition to the genetic analysis,
I also conduct live imaging analysis ofSGs. In the left figure, transgenic riceseeds in which amyloplasts (organelle
synthesizing SGs) are visualized withgreen fluorescent protein.

〓 Assoc. Prof.
MATSUSHIMA Ryo〓 Research Area : Signaling Mechanisms

Molecular genetic studies on the mechanisms forstress sensing and response in plants.
As autotrophic sessile organism, plants have developed unique systems to regulate biological phenomena such as development, environmental stressresponses, and reproduction process. To understandand manipulate the plant behavior, we have been
trying to describe the regulatory system for thesemolecules, deciphering the information possessed bythese plant signaling molecules by molecular genetic
approaches using model plants such as Arabidopsis.
In these years, we are investigating novel short-peptide factors involved in the regulation of iron homeostasis responding to environmental changes.

Establishment of data driven crop design technology.
It has been known that useful agronomical traits of crops are dependent on both the genetic factors the crop possesses and environmental factors the crop lives. Importantly, these two factors
are not independent and affect each other in a complex manner.

〓 Prof.
HIRAYAMA Takashi

We have been trying to identify the genetic factors
and environmental factors critical to useful traits bydescribing the life-course dynamics in physiological status of field crops associated with the environment data. Using these isolated determinants,
we successfully built models that can predict theagronomical traits at high accuracy. Such themodels enable us to design the crops with suitable
genetic factors to a given filed condition including
the forecasted climates in the near future.

Graduate School of Environmental and Life Science, Okayama University49

■ Introduction to Research〓 Research Area : Signaling Mechanisms

Study on Molecular Physiology of Stomatal Movement
against Air Pollutants
Yield loss of crops due to airborne pollutants is estimated as 3040% near future in Japan. Plants equip the mechanism to withstand such pollutants. One of the major mechanisms is elucidated
as closing stomata to prevent the entry of gaseous toxicants. To
gain insight into the molecular basis of plant response to airborne
pollutant, I employ molecular genetic and physiological approaches
to comprehend stress signaling mechanism of stomata.

Ion Dynamics Study of Stomata, Roots and Inside of Leaves.

〓 Assoc. Prof.
MORI Izumi

Although plants seems calm, silent and static, it is not
real. Plants are always active and dynamic. For example,
stomata move every day, every minute; tendrils move spiral around and root architecture keeps changing. Thesemovement of plants are more or less associated withthe mobilization of ions. I am an expert in ion dynamics
study through electrophysiological techniques. My main
research focuses are Ca2+ ion transport in guard cells andCO2 transport in mesophyll cells, which play crucial rolesin photosynthesis under biotic and abiotic stresses.

Plant Hormone Quantification.

In addition to physiological analysis, chemical analysis using LC-MS is one of my missions as a
stuff of Institute of Plant Science and Resources, Okayama University. I am taking a part of thecomprehensive plant hormone quantification analysis group. Our group is having a large numberof collaborators from all around the world.

〓 Research Area : Signaling Mechanisms

Epigenetic regulation mechanisms of gene and transposon expression in plants
Genetic information is encoded in DNA base sequences. However, epigenetic information outside of the DNA sequence also has been found to play an important role in gene and transposon
expression. Such epigenetic information including DNA methylation and histone modification is
known to be affected by the stage of
growth and changes in the environment. My research interests are: i) the
molecular mechanism that controls
epigenetic status in plants; ii) theways in which epigenetic informationis transmitted to the next generation;and iii) the study on the variety and thechange of epigenetic regulation systems in plant evolution.

Analysis of transcriptional gene silencing mechanism in Arabidopsis〓 Assoc. Prof.
IKEDA Yoko

50

To reveal the mechanism of epigenetic gene silencing, we
did mutant screening affecting transcriptional gene silencing
in Arabidopsis thaliana , and recently identified new factors
for transcriptional gene silencing. Arabidopsis thaliana isuseful material for genetic analysis, but we also utilize several plant species for research e.g. barley, seaweed, andliverwort Marchantia polymorpha to analyze the function of
epigenetic regulation in plant evolution.

〓 Research Area : Plant Cytomolecular Biochemistry

Genome-wide expression analysis of reactive oxygen species
gene network in plants grown in long-term spaceflightSpaceflight environment have been shown to generate reactive oxygen species (ROS) and induce oxidative stress in plants, but little is known about the gene expression of the ROS gene
network in plants grown in long-term spaceflight. The molecular response and adaptation to thespaceflight environmentof plants harvested after
27 days of cultivation
onboard the International
Space Station (ISS) havebeen measured using genome-wide mRNA expression analysis.
Crop grown in International
Space Station (©NASA)ROS network induced in plants
grown in space (red arrows)

Gene expression analysis in plants exposed to UV irradiation〓 Assoc. Prof.
SUGIMOTO Manabu

Plants should be necessary to self-supply foods
when astronauts would stay during long-term
space travel and habitation on the Moon andMars. Thought the sunlight is the most importanceto plants, UV presenting the sunlight can damage
many aspects of plant processes at the physiological and DNA level. Especially UV-C, which iseliminated by the stratospheric ozone layer, is suspected to be extremely harmful and give a deadly
injury to plants in space. The molecular response
to UV irradiation of plants have been analyzed.

Expression level of genes in plants
exposed to UV-C irradiation〓 Research Area : Plant Stress Responses

Molecular mechanisms of aluminum tolerance inplants
Aluminum (Al) toxicity is a major factor limiting crop
production on acid soils. However, some plant species
or accessions have evolved strategies to cope with Al.
Rice is the most Al-tolerant species among small graincereal crops. We identified a transcription factor for Al
tolerance (ART1) and found that it regulates at least 32
genes implicated in Al tolerance. On the other hand,barley is the most sensitive cereal to Al toxicity, butthere is a large genotypic difference in Al tolerance. We
identified a major Al-tolerance gene in barley, HvAACT1.
Furthermore, we found that high expression of this geneis acquired by a transposon insertion in its promoter.

Transport system of mineral elements in plants〓 Prof.
MA Jian Feng

Mineral elements including essential, beneficial and toxic elements in soil affect both plant growth and humanhealth. We are working on identification of transporters
involved in uptake, root-to-shoot translocation and distribution/redistribution of these elements in plants. We
have identified a number of transporters for Si, P, Mg,
Mn, Zn, Cu, Fe, B, Cd and As. Especially, we foundthat rice has developed an efficient uptake system formineral elements, which is mediated by both influx andefflux transporters polarily localized at the exodermis
and endodermis of the roots. We also identified severaltransporter genes for accumulation of Cd and As in rice.

Graduate School of Environmental and Life Science, Okayama University51

■ Introduction to Research〓 Research Area : Plant Stress Responses
Mineral nutrients required for plant growthand development are taken up by the roots
from soil solution, and then delivered todifferent organs and tissues depending on
their requirements. In Poaceae, this selective distribution is mainly mediated in thenodes, which have highly developed andfully organized vascular systems. We foundthat “Inter-vascular transfer” of mineralelements from enlarged vascular bundles
to diffuse vascular bundles is required fortheir preferential distribution to developing
tissues and reproductive organs.

Studies on mineral distribution control systems in plants〓 Assoc. Prof.
YAMAJI Naoki

A number of transporters involved in this inter-vasculartransfer processes have been
identified mainly in rice. They
are localized at the different
cell layers and form an efficient machinery in the node.
These findings will be applicable to improve productivity,
nutritional value and safety of
cereal crops.
Representative references
Yamaji N. et al. Reducing phosphorus accumulation in rice grains with an impaired transporter in the node.
Nature 541:92-95. (2017)
Yamaji N. and Ma J.F. Node-controlled allocation of mineral elements in Poaceae. Current opinion in plantbiology 39:18-24. (2017)〓 Research Area : Plant Stress Responses

Studies on mineral transporter and its regulation
mechanisms in plants
Plants are important for us, having been utilized as indispensable materials for, food, clothing
and housing since ancient times. Therefore we couldn’t live without plants. I’m focusing on mineral transporters for healthy and high nutrient-efficient crop production.

>Molecular mechanisms of Si transport

Silicon (Si) is a beneficial element for plant
growth, which can alleviate many stresses byaccumulation in their shoots. However, Si content
of the plants varies greatly with species, and only
those plants that are capable of accumulating theelement can receive benefit from it. Rice is one ofmajor Si accumulating plants. I am focusing on the
study about molecular mechanisms of Si uptake
and accumulation in rice for applying the beneficial effects of this element in many other plants.

Wild-type rice and a low silicon
accumulation mutant. Growth and yields
in the mutant are extremely poor

>Identification of mineral redistribution transporters〓 Assoc. Prof.
MITANI-UENO Namiki

52

Plants require 14 mineral elements for their growth.
These elements are taken up by the roots, translocatedfrom the roots to shoots, followed by distribution/redistribution to different organs A number of transporters
for uptake and translocation of mineral elements havebeen identified, however, most transporters involved inmineral distribution/redistribution remain to be identified.
I am working on mineral redistribution systems in rice for
efficient use of mineral elements.

〓 Research Area : Plant Molecular Physiology

Water and ion transport in plants under salinity stress
Salinity stress is one of major abiotic stress that limit plant productivity in global agriculture. Salinity, usually high concentration of Na+, reduces water and mineral uptake in plant. I study root
hydraulic conductivity (Lpr) using the root pressure chamber method, because regulation of Lpr
is important to prevent dehydration and to cope with osmotic
imbalance in initial phase of
salinity stress. As for plant ion
transporters, cRNAs are injected into a frog Xenopus oocytes
and their properties (ion selectivity and activation mechanism)
are investigated electrophysiologicaly to reveal what and howtransporters regulate ion flux
under salinity stress.

Aquaporins transporting water and low-molecularweight compounds〓 Prof.
KATSUHARA Maki

Aquaporins was first identified as a membraneprotein exhibiting permeability for water when
faced with an osmotic gradient. Now it is reported that several aquaporins facilitate the transport
of not only water but also other low-molecularweight substrates such as glycerol, ammonia,
silicic acid, arsenite, boric acid, and carbon
dioxide. I study rice and barely aquaporins toimprove plant growth and stress tolerance via
aquaporin functions.

〓 Research Area : Plant Molecular Physiology

Research on function and structure of plant-specificmalate transporters
Aluminum (Al) ion is a major inhibitory factor of plant growth in acidic soils which comprisealmost 40% of the world arable land. Toxic Al cations (Al3+) rapidly inhibit root growth and prevent subsequent uptake of water and nutrients. The mechanisms of Al toxicity and tolerance
are analyzing using a cultured cell system and whole plants. Especially Al-tolerance mechanism, wheat ALMT1 gene encoding Al-activated malate transporter was found by our group,and demonstrated as Al-tolerant as well as acidic-soil tolerant gene, for the first time in crops.
In addition, since the ALMT gene and its homologues have been found only in plants, the diversity of physiological functions for individual ALMT genes was elucidated as recent studies.
The molecular details of the structure and functions and the expression mechanisms of thesetransporters are now studied.

A gene encoding aluminum (Al)-activatedmalate transporter (ALMT1) regulates Al
tolerance of wheat.

〓 Assoc. Prof.
SASAKI Takayuki

It was previously shown that Al tolerance inwheat (Triticum aestivum L.) is correlated with
the Al-activated efflux of malate which chelates
and detoxifies Al cations around root apices.
To isolate the gene involved in this mechanism,
Sasaki et al. (2004, Plant J.) examined a pairof near-isogenic wheat lines that differed in Al
tolerance at a single genetic locus, and founda gene which shows greater expression in theroot apices of ET8 (the Al-tolerant line) thanthat of ES8 (the sensitive line), as depicted in the photograph. The gene is named ALMT1 which
encodes a novel transporter protein facilitating the Al-activated efflux of malate and is a major
Al-tolerant gene of wheat.

Graduate School of Environmental and Life Science, Okayama University53

■ Introduction to Research〓 Research Area : Plant Molecular Physiology

Study of factors related to seed dormancy andgermination
Pre-harvest sprouting (PHS) is one of the most serious issues
affecting cereal cultivation because it reduces the quality ofcrops. In some countries including Japan, high humidity andlow temperature during the late ripening and harvesting of
wheat seeds damages grains due to PHS. Therefore, themechanisms underlying seed dormancy and germinationneed to be elucidated in more detail. I am analyzing some
genes and proteins, MOTHER OF FT AND TFL1 (MFT) andbZIP transcription factors, which were upregulated after physiological maturity in dormant seeds.

Figure 4. ABA sensitivity of WT and T4
seeds of TaABF over-expressed transformants in Arabidopsis.

Mechanisms of the water control by plant aquaporins
Most seeds form an embryo and store starch andnutrients, which are necessary for germination and development at the early stage, and are then desiccatedand maintained under desiccated conditions until germination. This suggests the existence of some mechanisms to control the inner water condition of cells
during the development and subsequent desiccation ofseeds. I focus on water channels, especially tonoplast
intrinsic proteins 3 (TIP3s), which highly accumulate
in seeds during seed development and desiccation,
and analyze its expression patterns and the regulation
mechanisms of water transport activity.

〓 Asst. Prof.
UTSUGI Shigeko〓 Research Area : Molecular Virology

Study on the interaction among plant/fungus/virus
toward virocontrol of phytopathogenic fungiUsing two combinations, Chestnut/chestnut
blight fungus/mycoviruses and fruit trees/
root rot fungi/mycoviruses, viral replicationand symptom expression were investigatedat the molecular and cellular levels. Obtained
knowledge and achieved technical advance
will be integrated into into virocontrol (a formof biological control using viruses) of theplant pathogenic fungi.

Research on neo-lifestyle of fungal viruses〓 Prof.
SUZUKI Nobuhiro

54

Several viruses, challenging the concept or rulesof viruses, have been discovered from lower
eukaryotes. The objective of this project is to reveal the unique neo-lifestyle of Yado-nushi virus
1 (YnV1) and Yado-nushi virus 1 (YnV1) newly
discovered from an important pathogen of perennial fruit trees, Rosellinia necatrix. We show that
YkV1 highjacks the capsid of YnV1 to heteroencapsidate YkV1 genomic RNA and replicase anduse it as the replication site. Furthermore, viruses with similar mutualistic virus/virus interactions
will be found in other eukaryotic organisms toshow the generality of the neo-lifestyle.

〓 Research Area : Molecular Virology

Study on viromes in crop phytobiomes
Phytobiomes refer to the complex networks between
plants and their associated communities of organisms
including bacteria, fungi, viruses and invertebrates.
Phytobiomes are becoming increasingly recognized asimportant factors in plant health and productivity, but inparticular, little is known about the diversities of virus
communities in agricultural cropping system. Taking
advances of the next generation sequencing and metagenomics, our group studies on viromes in fungi andinsects that are associated with crop plants. We aim tofind out whether these viral communities influence theirhosts and promote the health and growth of crop plants.

Study of non-retroviral RNA virus-like elements in the
genome of the plants, insects and fungi
The availability of genome sequences of a large number of eukaryotes has led to the discovery of endogenous non-retroviral RNA virus-like elements, also
known as endogenous viral elements (EVEs). Theseelements are considered as fossil of RNA virus integrated into host genomes by as-yet-unknown mechanisms. To gain deeper insight into the long-term viralevolution and host-virus coevolution, our research is
focused on identification and analysis of the EVEs in
the genome of the plants, insects and fungi.

〓 Assoc. Prof.
KONDO Hideki〓 Research Area : Molecular Virology

Plant-Virus interactions〓 Assoc. Prof.
HYODO Kiwamu

Plants are constantly attacked by various kinds of pathogens and pests, resulting in 40% yield
losses annually. Among plant pathogens that pose a major threat to sustainable agriculture andglobal food security, viruses account for nearly half of the plant endemics and cause estimatedeconomic losses more than US$30 billion annually. Positive-sense single-stranded (+ss)RNA
viruses are the most abundant in plant viruses and cause the economically important diseases inmajor vegetable and field crops worldwide. The vast majority of plant (+)ssRNA viruses are very
simple entities comprising a nucleic acid genome encoding from 4 to 11 viral proteins needed
for genome replication, local and systemic spread within the host plant, and transmission to a
new host. Despite the simple nature of these pathogens, there is still much to be learned about
how they interact with their hosts and cause disease. Understanding the molecular mechanisms
underlying pathogenicity of (+)ssRNA viruses is a crucial step towards the design of effective
strategies for crop protection.
In general, virally encoded proteins have a multifunctional property with the potential to interact
with several virus- and host-derived molecules, thus creating a complex web of molecular interactions in infected cells. Because of the limited number of viral-encoded proteins, (+)ssRNA
viruses need to subvert the host cell machinery for their own vital functions, ultimately creating acellular environment favorable to the infection. For this purpose, (+)ssRNA plant viruses co-opt
an array of host-derived factors (referred to as proviral host factors) to establish viral infection, in
which viruses remodel their functions to facilitate every step of the viral life cycle. The identification of the global landscape of plant-virus interactions at the molecular level is key to understandhow the virus hijacks the host cell to facilitate infection.
Our research aims at deciphering the molecular network of plant-virus interactions using (+)
ssRNA plant viruses as models. Discoveries in this area will provide insight into host-virus interactions as well as identify new breeding targets for the development of virus-resistant crops.

Graduate School of Environmental and Life Science, Okayama University

55

■ Introduction to Research〓 Research Area : Plant-Insect Interactions

Understanding of metabolic defense against
herbivores in plants〓 Prof.
GALIS Ivan

Plants activate powerful protective shield against feeding herbivores that involves biosynthesis of various toxic phytoalexins.
While spectrum of phytoalexins in plants is vast, their biosynthesis and regulation during herbivory are less known. We use
monocot plant models, including rice and sorghum, to identify
novel metabolic patterns associated with herbivory. We look fortranscriptional regulators involved in the regulation of biosynthetic genes for these compounds, in particular those induced
in response to herbivore attack. We also study the role of plant
hormones as secondary messengers in defense signaling pathways against herbivores.

Research on perception of herbivory in plants
The strength of plant defense largely depends on early detection of elicitor moleculesfrom herbivores which are deposited in plantwounds during feeding. As the number ofidentified elicitors is still limited, we aim identification of novel elicitors using rice plants
and their herbivores as our model systems.
We develop efficient bioassays for rapid detection and isolation of novel compounds, usebiochemical techniques for their characterization, and intact plants for functional analysesof these novel herbivory-associated molecular patterns (HAMPs).

〓 Assoc. Prof.
SHINYA Tomonori〓 Research Area : Plant-Pathogen Interactions

Involvement of phytocytokines in rice immunity
Plants cleverly regulate their immunity by secreting endogenous peptides called plant cytokines (phytocytokines). We
believe that understanding and optimizing phytocytokine signaling and their
networks will improve plant immunity, and we are conducting this research.
Recently, we have established a multi-omics pipeline to isolate potential
phytocytokines in rice and identified 236 endogenous secreted peptides thatwere induced during the disease resistance response (Plant Biotech J 2020).
These included cytokine-like peptides such as the cysteine-rich RALF7, thepost-translationally modified PSK4, and a novel family of IRPs that do notcontain any known domains. Further analysis revealed that IRPs do indeed
have cytokine activity and act as positive regulators of resistance to blast fungus, the most important pathogen of rice (bioRxiv 2021).

Effector-triggered immunity through small GTPase
OsRac1〓 Prof.
KAWANO Yoji

56

Resistance (R) proteins are crucial intracellular receptors that detect attacks by insects and invasion by various pathogens,including fungi, bacteria and viruses. However, the signaling molecules which mediate R protein-induced immune responses
are not yet fully understood. We have previously shown that an intracellular switch, the small GTPase OsRac1, is a master
regulator controlling immunity in rice (Plant Cell 2016, Curr Genomic 2016, FPS 2014, COPB 2013, Rice 2010). However,
the mechanism by which OsRac1 receives signals from the immune receptors and becomes activated has remained unclear.
Thus, we explored OsRac1-binding proteins and identified the R protein Pit, which is an immune receptor for rice blast fungus, a prominent microbial disease of rice. Through various analyses, wedemonstrated that OsRac1 functions as a molecular switch, controlling ROS
production and hypersensitive cell death (CHM 2010) and a GDP/GTP exchanger OsSPK1 mediates the activation of OsRac1 by Pit1 (PNAS 2018).
Besides, we have found that anchoring Pit to the plasma membrane throughpalmitoylation, a type of lipid modification, is required for Pit-induced activation of OsRac1 on the plasma membrane (JBC 2014). Our work has therefore revealed the signaling pathway of the R protein Pit through OsRac1.

〓 Research Area : Plant-Environmental Microbiology

Lanthanide-dependent enzyme and motility
in plant-associating methylotrophic bacteria
Plant emit large quantities of methanol through stomata as aresult of their growth and pectin degradation. Methanol canbe a good nutrient for bacteria and methanol-utilizing (methylotrophic) bacteria predominate on the aerial plant surface(phyllosphere). We focus on their methanol metabolism andsymbiosis with plants.
Methylobacterium species are commonly found in phyllosphere, and they can promote plant growth. They have methanol dehydrogenase (MDH) to oxidize methanol. Not only calcium-dependent MDH encoded by mxaF, recently it was foundthat lanthanide-dependent MDH is also encoded by xoxF in
the genomes of Methylobacterium species. This is the first enzyme described to date, to contain lanthanide. We investigate
the mechanism of expression switching between these MDHs,
depending on the availability of lanthanide.
We also study molecular mechanism of the motility and chemotaxis in methylotrophs, which is important for the bacteria
to find and colonize plants. The chemotaxis is also affected by
the carbon source and lanthanide.

〓 Assoc. Prof.
TANI Akio

We have found new methylotrophic bacteria belonging tonovel genera. They have been isolated from rice rhizosphereusing lanthanide as an essential cofactor. They are named as
Oharaeibacter diazotrophicus SM30 and Novimethylophilus
kurashikiensis La2-4. Thus, lanthanide can be used for isolation of bacteria that contain xoxF, which can be found in manyso-believed non-methylotrophic bacteria and novel bacteria.

Methylobacterium aquaticum strain 22A

Strain 22A adhering plant root hair

Strain 22A chemotaxis toward methanol

Novimethylophilus kurashikiensis La2-4〓 Research Area : Plant-Environmental Microbiology

Study on dynamics of Phytoplankon in environment
Our group focuses on the study of Heterosigma akashiwo,
a unicellular alga that forms harmful algal bloom (commonly
termed ‘red tide’) . Algal bloom is typically caused by aberrant
propagation of a single species, resulting in its predominationin the local population. While environmental factors including
temperature and eutrophication are linked to bloom, the precise mechanism of its formation process is still obscure. We
isolated a bacterial strain, Altererythrobacter ishigakiensis,
a member of the class Alphaproteobacteria, that promotes
growth of Heterosigma akashiwo.This is the first example of
selective growth promotion of H. akashiwo by a marine bacterium, and may exemplify importance of symbiotic bacteriumon algal bloom forming process in general.

A bloom causative phytoplankton,
Heterosigma akashiwo

Study on interaction between a giant doube-stranded
DNA virus and its host〓 Assoc. Prof.
UEKI Shoko
HaV infect and lyse its host,
Heterosigma akashiwo. The
virus was identified as a bloom
terminating factor.

H. akashiwo bloom is known to be terminated by algicidal bacteria
and viruses. Heterosigma akashiwo virus (HaV) was identified as oneof such bloom-terminating factors. We completed the sequencing of
its genomes. The virual genome was characterized to be a linear double stranded DNA (dsDNA), with an estimated size of ~290 kbp. It is amember of Phycodnaviridae, one of the viral families regarded as “giant
dsDNA viruses” that possess genomes larger than several hundred-kbp
in size.
We are particularly interested in studying about the infection mechanismof HaV at cellular and molecular level. The study will provide insights
into infection strategies of a giant dsDNA virus, and the molecular mechanism of a major environmental phenomenon, bloom termination.
Graduate School of Environmental and Life Science, Okayama University

57

■ Introduction to Research〓 Research Area : Plant Diversity Analysis

Preservation and application of genetic and genomic
resources in barley
Ca. 15,000 accessions of wild and cultivated barleys
and a wide range of experimental strains are preserved with a support from the National Bioresrouce
Project. Genomic libraries and extensive cDNA resources have been developed for genomic analysis ofbarley which contributed to estimate gene regions on
the draft barley genome sequence published in 2012.
These genetic and genomic resources are used to
identify agriculturally important genes on barley genome. We also found that barley and diploid wheatshared the same genomic structure and barley canbe used as a diploid model of the Triticeae species,
including wheat, barley and rye.

Gene isolation in barley
The study focuses on isolation and characterization ofgenes controlling industrially important traits using the
genome diversity of barley. A recent example is a genecorresponding for barley seed dormancy (Qsd1), whichis associated with pre-harvest sprouting and malting for
brewing beer. Our analysis using a wild barley accession
harboring a strong grain dormancy revealed novel insight
into the genetic mechanism regulation grain dormancy inbarley (Sato et al. 2016 Nat. Commun.).
The orthologous genes are also existed in wheat genomes which will be important to control seed dormancy
in wheat.

〓 Prof.
SATO Kazuhiro〓 Research Area : Plant Diversity Analysis

Study on genetic diversity of crop species towardachieving sustainable crop productivity
Genetic diversity of target species is indispensable sources to breed new crop varieties to overcome food shortages under global environmental changes and population explosions. IPSR
preserves more than 10,000 barley germplasm as not only for the research materials for plantscience but also future resources to improve this crop species. The aims of our seed-bank activity
as well as our research projects are to grasp the degree of the variation of traits associated withstress tolerance and ‘high-yield’ productivity and to understand genetic structure of the trait formining the phenotypic diversity.
Deciphering the genetic diversity of domesticated barley spreading the entire world, we are evaluating agronomic traits such as vernalization requirement and salt tolerance at the germination
stage. Genomic variation of the barley materials is explored using the next generation sequencing(NGS) technologies to make advances in our barley domestication history research. To uncover
the genetic structure of the agronomic traits, multiple mapping populations such as recombinant
inbred lines (RIL), chromosome segment substitution lines (CSSL) and nested association mapping population (NAM) are also developing, and the quantitative trait loci (QTL) corresponding to
the agronomic traits are identifying.

〓 Assoc. Prof.
SAISHO Daisuke

58〓 Research Area : Plant Diversity Analysis

Identification of the genes responsible fortransformation amenability in barley
Different plant cultivars of the same genus and species
can exhibit vastly different genetic transformation efficiencies. However, the genetic factors underlying these differences in transformation rate remain largely unknown. Inbarley (Hordeum vulgare), ‘Golden Promise’ is the mostuseful and well-studied cultivar for genetic transformation.
By contrast, cultivar ‘Haruna Nijo’ is recalcitrant to genetic
manipulation, although numerous genomic resources
have been developed for this haplotype. Recently, we
identified three major genomic regions on chromosomes
2H and 3H in barley important for successful transformation with Agrobacterium, utilizing the ‘Haruna Nijo’ ×‘Golden Promise’ F2 generation. We termed these loci as
Fig. Green shoots regenerating
Transformation Amenability (TFA) responsible for Agrofrom callus of barleybacterium-mediated transformation.
The genomic regions identified herein likely include necessary factors (i.e. regeneration from
callus) for Agrobacterium-mediated transformation in barley. The potential to introduce these lociinto any haplotype of barley opens the door to increasing the efficiency of transformation for target alleles into any haplotype of barley by the TFA-based selection method. Now we are trying toisolate the genes responsible for TFAs.

〓 Assoc. Prof.
HISANO Hiroshi

Genome editing in barley

Genome editing is a new technology of genetic engineering in which DNA is inserted, replaced,or removed from a target genome sequence using artificial restriction enzymes (nucleases). We
are now developing a method of mutagenesis by the Clustered Regularly Interspaced Short Palindromic Repeats /CRISPR-associated proteins 9 (CRISPR/Cas9) or other techniques for future
breeding and functional genomics in barley.

〓 Research Area : Plant Functional Genomics

Molecular dissection of beneficial genes in barley
Barley is typically characterized by grains with inseparable chaffs. A single mutation event produced
a free-threshing variant, called naked barley, about
8,000 years ago somewhere in the Near East. We
clarified the genes controlling naked caryopsis(nud), which is suitable for food rich in soluble
dietary fiber (wax.b). We are also interested in photosynthesis of non-foliar tissues, such as awns andspikes for improved productivity and quality. Using
short awn (lks2) mutants and white spike (albino
lemma 1) mutants, we are clarifying their contribution to photosynthesis and grain yield in barley.

Chromosome manipulation of wheat with introduced
barley segments
Through intergeneric hybridization between wheat
and barley, we aim to produce unique wheat lines
with introduced tiny barley chromosome segmentswith useful genes. These target genes are expected to confer higher dietary fiber content in seeds
and improved disease resistance.

〓 Prof.
TAKETA Shin

Graduate School of Environmental and Life Science, Okayama University

59

■ Introduction to Research〓 Research Area : Integrated Genomic Breeding

Development of remote cross breeding in rice via polyploidization
For breeding of super rice varieties with useful new genes,
it is important to promote allelic exchange in existing cultivars by crossing them with wild or genetically remotecultivars. However, hybrids are rarely obtained from such
distant crosses due to multitude of reproductive barriers.
Interestingly, we found a fertile tetraploid progeny derived
from anther culture of Asian rice cultivar, O. sativa , and African rice cultivar, O. glaberrima . Using genomic and phenotypic analyses, we now aim to clarify mechanisms involved
in recovery of seed set in these plants. Furthermore, we
hope to establish a novel remote cross breeding strategy inrice that overcomes reproductive barriers by introduction ofpolyploidization and haploidization.

Genetic dynamics in rice multiparent cross population
The expansion of genetic diversity in crossed
populations is essential for faster and more
efficient crop improvements. To overcome alimiting factor of biallelic gene combinations
in rice breeding that depends on classical
2-way crosses, we developed a new multiparent population using 8-way cross strategy.
By comparing genomic and phenotypic dynamics of this population, with those found inusual 2-way populations or parents, we aim
to demonstrate the usefulness of multiparent
populations for genetic improvement and development of novel breeding approaches inrice.

〓 Prof.
YAMAMOTO Toshio〓 Research Area : Integrated Genomic Breeding

Analyses of kinetochore components of plant and its applications
We have been conducting molecular cytogenetic studies on the
structure and function of nuclei and chromosomes using plant species. Kinetochores have been our main research subjects among
functional chromosomal elements. We have been conducting basic
research on the kinetochores, and have identified kinetochore components from various plant species including many crops. Additionally, we have conducting applied research including “constructionof plant artificial chromosome (chromosome vector)” and “haploid
production” using knowledge of the basic researches.

Analyses of epigenetic status in plants
Epigenetic regulation plays important roles in all aspects of plant life activities including development and stress responses. Epigenetic modifications of individual cells in plant organs/tissues
are considered to be individually controlled, but it is difficult to know how each cell is modified bycurrent methods. In order to solve this problem and to obtain epigenetic modification informationof individual cells, we are developing epigenetic modification analysis methods using immunohistochemical staining, which provides a bird's-eye view and single cell-level resolution keeping
positional information of individual cells in organs/tissues.

〓 Assoc. Prof.
NAGAKI Kiyotaka

60〓 Research Area : Integrated Genomic Breeding

Boosting up crop breeding by integrated bioinformatics
and statistical genetics
Along with drastically changing our lives, computers have also brought a paradigm shift in plant
breeding. “Genomic breeding” is a state-of-the-art method which integrates genome-wide genotype information to model and predict phenotypic variation in populations. Although modern computer-based methods have strong potential for accelerating the development of new varieties,
statistical models used in the method still need improvements to capture in detail events happening in real nature.
At present, we try to integrate all useful environmental
and biological data into new statistical models for genomic breeding that will allow accurate phenotype prediction
within relatively small datasets. We apply a large variety
of modeling methods that also include machine learning
strategies. We hope that our work will boost up breedingin the future, helping to overcome the global shortage infood production experienced worldwide.

Exploring genetic diversity for discovery of novel beneficial
genes and improved crop productivity
In addition to methodological approaches, we also use real plants to discover novel genes leading to practical improvements of rice. Currently, African cultivated rice Oryza glaberrima is our main genetic target and sourcefor variety of stress tolerance-related genes. In particular, we hope that O.
glaberrima will provide us with beneficial genes to promote rice yield evenunder harsh environments that spread as a result of global warming in thecurrent era.

〓 Asst. Prof.
FURUTA Tomoyuki〓 Research Area : Plant Diversity and Evolution

Evolution of photoreceptors
Modifying sensitivities to environmental signals is one of fundamental mechanisms for plants to optimize
adaptive responses to environmental differences and lead to their diversification on the earth. Since photoreceptors play pivotal roles for plants to sense environmental signals and adjust their physiological responses such as germination and flowering, natural variations on photoreceptors are possibly responsible
for such adaptive evolution in plants.
By focusing on phytochromes, we performed multiple approaches including molecular evolution, plant
physiology, and genetics and attempt to (1) explore
natural variation on phytochrome genes, (2) investigate
physiological as well as phenotypic changes that wereconferred by amino-acid changes on phytochromes, (3)unravel molecular mechanisms underlying phenotypicvariations.

Phylogeography of alpine plants and molecular basisof adaptation to regional environments〓 Assoc. Prof.
IKEDA Hajime

Alpine as well as arctic-alpine plants have specifically extensive ranges in
the northern hemisphere and plausibly encounter various environments atsome parts of their ranges. We are interested how alpine plants adapt tosuch various environments.
By conducting phylogeographic studies, (1) we attempt to examine whether
adaptation is responsible for genetic changes or phenotypic plasticity. If genetic changes are responsible for adaptive divergences, we have two further
questions: (2) what kind of genes are important for adaptive divergence and(3) is there any mechanisms (genes) that are shared across various species.
In addition to these evolutionary interests, we are interested in how alpine
communities have been established following the past climate changes, especially glacial and interglacial cycles during the late Pleistocene.

Graduate School of Environmental and Life Science, Okayama University

61

■ Introduction to Research〓 Research Area : Plant Diversity and Evolution

Study on taxonomic reevaluation and conservation ofwild plants

Previous plant taxonomic systems based on morphology had often disagreed with the molecularphylogenetic trees. I have advanced taxonomical reevaluation based on morphology and molecularphylogeny on family Asparagaceae, Tofieldiaceae, Dioscoreaceae, Cyperaceae, etc.
For conserving local populations of endangered plant
species, I am investigating their fluctuation, and studying
on hybridization and genetic disturbance of the species.
For ex-situ conservation, frozen seeds from the local
populations of endangered plants have been preserved.
For example, I have surveyed a lot of wild populations of
Rumex nepalensis subsp. andreaeanus in Okayama andadjacent area, and found new hybrids of the subspecies.

Genetic resources of wild plants
About 17,000 frozen seed accessions of 3,500 wild plant species
from wild populations are available for scientific studies. Those are notguaranteed for survival rate. Exchanging MTA is needed before using
the seeds. An herbarium is also available for studies on weekdays.
About 80,000 specimens of 6,000 wild plant species from Japan andother countries have been preserved under APG system. They include
various weeds from the world, naturalized plants in Japan, endangered
species, plants of Ryukyu, and so on. About 30,000 dried seed specimens are also available. Please contact me (junyama@okayama-u.
ac.jp) to access the genetic resources and herbarium.

〓 Asst. Prof.
YAMASHITA Jun〓 Research Area : Genetic Engineering

Role of flagella, flagellin glycosyation and flagella-mediated chemotaxis in virulence of Pseudomonas syringae pv. tabaci 6605 (Pta6605)
Understanding the mechanisms by which phytopathogens express their virulence is crucial forcontrolling plant diseases. Using Gram-negative phytopathogen Pseudomonas syringae pv.
tabaci 6605 (Pta6605) as a model pathogen, we revealed that flagella-defective mutant (∆fliC)
lost surface motility and reduced virulence. Furthermore, flagellin-glycosylation-defective mutant(∆fgt1) remarkably reduced surface motility and virulence. These results indicate that flagellaand flagellin glycosylation are important for surface motility and virulence. To examine whether
motility with directionality is required in virulence we generated several mutants for chemotaxis.
Although there are two sets of chemotaxis gene cluster (cheⅠ and cheⅡ ), we found that cheⅡ
is required for virulence in Pta6605. In general, compared with animal pathogenic bacteria, plant
pathogenic bacteria have a large number of chemotactic receptor genes, mcp. Pta6605 also
has 53 mcp genes and among them we revealed that one mcp encoding the chemoreceptor
for gamma-aminobutyric acid and two mcp encoding the chemorecepotrs for amino acids areimportant for bacterial infection.
Analysis of role of other Mcp
proteins in plant infection is now
under investigation.

〓 Prof.
ICHINOSE Yuki

62〓 Research Area : Genetic Engineering

Elucidation of the regulatory mechanism of plant immune
responses by focusing on MAMP-responsive phosphoproteins

Plants have a defense mechanism to protect themselves from infection
by various pathogens. An understanding of the defense mechanismsof plants is essential for efficient plant breeding. Pattern recognition
receptors (PRRs) on the cell membrane recognize the basic structure(Microbe-associated molecular pattern: MAMP) of the microorganismand exert resistance. Many PRRs contain protein kinase domains and,after MAMP recognition, transmit signals downstream via protein phosphorylation. In other words, if we can elucidate the function of proteins
whose phosphorylation changes with MAMP recognition, it will help
us to understand the molecular mechanism of disease resistance. We
have identified several MAMP-responsive phosphoproteins and areinvestigating the role of their resistance mechanisms.

Elucidation of the virulence regulatory mechanism ofphytopathogenic bacteria
Plant pathogens have evolved various molecular mechanisms
to establish infection in the host plant. On the other hand, evenplant pathogenic bacteria that can establish infections in plants
have different pathogenicity to host plant. The clarification of themolecular mechanisms involved in the exertion of pathogenicity
is expected to lead to the development of more efficient drugs
and the establishment of infection prevention methods. Currently, we are clarifying the differences in pathogenicity between
multiple strains and searching for gene regions important for
pathogenicity through comparative genomic analysis.

〓 Assoc. Prof.
MATSUI Hidenori〓 Research Area : Plant Genome Dynamics Analysis

Study on genetic and genomic analyses for plant
breeding
We are engaged in genetic and breeding research by using next-generation sequencing technology (NGS) for various crop species. Our research has been mainly conducted on the hexaploid

crop species called sweetpotato (Ipomoea batatas (L.) Lam.). Sweetpotato is one of the mostimportant crop species in the world, and the annual production in the world exceeds 100 million

tons (FAO). There is a need to develop high value-added varieties to which excellent traits suchas pest resistance, yield and taste have been imparted. However, sweetpotato is geneticallycomplicated, and its genetic analysis has been considered extremely difficult. In such a situa-tion, our groups succeeded in genome-wide genetic analysis by using NGS in sweetpotato. We
identified genetic regions related to agricultural traits such as disease and pest resistance byperforming QTL analysis and GWAS (Genome-wide association study). Using these research
results, we developed selective DNA markers useful for breeding.

〓 Assoc. Prof.
MONDEN Yuki

Graduate School of Environmental and Life Science, Okayama University

63

■ Introduction to Research〓 Research Area : Plant Pathology

Unrabeling plant disease susceptibility to fungal
pathogens

Multi-layered defense barriers ensure that a plant is the host to only a few adapted pathogens.
Thus, the host range of a particular plant pathogen relies on its ability to fully suppress plant
defense responses such as the pattern-triggered immunity (PTI). One of the common pathogen
strategies to overcome PTI is the production of a plant defense suppressor. In the case of Mycosphaerella pinodes , a causal agent of Mycosphaerella blight on pea, this fungus can avoid hostdefense responses by secreting at least two suppressors named supprescins A and B (Fig. 1),
which manipulate the physiology of the host cells, including JA biosynthesis through targetingthe host’s ATPase. In parallel, a constituent(s) similar to the fungal supprescins has been discovered in healthy leaves of pea. Such a constituent was also found in the healthy leaves of barleyand Arabidopsis plants, and collectively referred to as an endogenous suppressor (ES). Actually,
the purified ES can suppress or delay PTI, enabling the non-adapted pathogen to cause disease
symptom on corresponding plants. Interestingly, the action of the pea ES is quite similar to thatof the supprescins A and B secreted by M. pinodes . Consistently, the ES can severely inhibit
host’s ATPase, temporarily reducing the ability of the host cell to defend itself. The putative roleof the ES is assumed to be involved in the trade-offs between plant growth and defense by preventing excessive defense responses against pathogen attack. Alternatively, it is likely used bya pathogen to promote disease susceptibility. We are now focusing on the host cell physiology
altered by a pathogen- and/or plant-derived suppressors in relation to the convergent evolution
between pathogen and host.

〓 Prof.
TOYODA Kazuhiro

Chemical structures ofFig. 1.
Supprescins A and B from Mycoso phaerella pinodes . (a) Chemical structures of Supprescin A (upper ) and B(lower ). The common moiety consistingof O-glycosyl portion attached to theserine (GalNAc-Ser-Ser-Gly) is proposed to be essential for suppressor activity. (b) A predicted structure (left ) of the Supprescin B, a major
suppressor of M. pinodes and its distribution of charge around this molecule (right ).

〓 Research Area : Plant Pathology

For the control of crop diseases caused by a fungal
pathogen Rhizoctonia solani
Rhizoctonia solani is a soil-borne fungal phytopathogen causing rice
sheath blight as well as seedling damping-off or root rot in various
crops. Management of this pest is difficult and it gives rise to serious
damage in agriculture and economies. An experimental pathosystemusing Brachypodium distachyon, an emerging model plant, revealed
plant immunity mechanism against this pathogen leading to a novel
insight into the fungal infection strategy. Fungal proteinaceous weapons
called effectors are now being investigated.

Molecular basis of a biological control agent for crowngall disease in grapevine
Grape is one of the major fruits produced in Okayama. It suffers serious damage from grown gall disease which is caused by Rhizobium
vitis Ti strain. A non-pathogenic strains of R. vitis have been isolated
as biological control of this pest. The molecular mechanism underlying
this suppression activity is investigating and we found a potential causal substance produced by this biocontrol agent.

〓 Assoc. Prof.
NOUTOSHI Yoshiteru

64

Isolation and characterization of plant defense activators for sustainable agriculture
Plant defense activators exhibit cop protection activity by priming or inducing plant
immune response. We established a quantitative assay method for plant defense
response and identified potential compounds through a high-throughput screeningof several commercial libraries of organic small molecules as well as a laboratory-made small cyclic peptides. They can be used for not only lead compounds todevelop agrochemicals but also molecular probe to understand plant immunity.

〓 Research Area : Plant Genetics and Breeding

Genetic study on instability of flowering time in wheat
and barley under global warming conditions
Global climate change has a huge impact on crop production. For wheat and barley productionin Japan, warm winter has been arising as a serious problem which would cause yield decrease
and low quality.
So far, early-flowering (heading) varieties of wheat and barley have been developed to avoid
pre-harvest sprouting and Fusarium head blight, which could often be caused by monsoonal rain
during maturing and harvesting stages. However, most of early-flowering varieties show “instabilityof flowering time” in response to ambient temperature. They differentiate young spike primordium
extremely earlier in warmer winter than in ordinary years. Unexpectedly precocious spike development will result in yield decrease due to less biomass production and frost injury caused bytransient chills in early spring.
To solve the problem, it is necessary to disclose genetic mechanism underlying the instability offlowering time. For this goal, we are working on (1) identification of novel flowering-time genes
and their interaction with other flowering-time genes, (2) finding genes which do not promote
flowering very much even under warm winter condition, and (3) disclosing the genetic mechanism
underlying the instability of flowering through molecular genetic study.

〓 Assoc. Prof.
NISHIDA Hidetaka〓 Research Area : Postharvest Horticulture

Prediction of qualities and disorders of fruits and vegetables, by “DEEP LEARNING”
Deep learning system enables us to reproduce professionaleyes on the qualities & disorders of fruits and vegetables,
potentially acting as prompt prediction. This technique also
might be applicable to prediction of the preferences in marketing or of patterns of DNA sequences, etc. Furthermore, recent progress in back propagation of neural network enabledvisualization of “what is a deep learning model looking”, developing further utilization of this technology.

Research on fruit “shapes” and “ripening”

As major characters affecting fruit quality, shape and ripening
are our research targets, with genome-wide transcriptomic or
genetic approaches. Persimmon ( 柿 ) shows a wide diversity intheir fruit shape and ripening. Utilizing their genetic diversities,
with GWAS and/or transcriptomic network analyses, we areattempting to identify genetic factors conferring various shapes
and ripening characters. Also, planning to launch onto tomato
ripening system, focusing on evolutionally conserved ethylene
receptors and chemical compounds accessible to them.

Study on sex determination in horticultural crops〓 Assoc. Prof.
AKAGI Takashi

Sexuality is one of the most important strategies to maintain the genetic
diversity within a species. In horticultural crops, the sexuality also involves
breeding, cultivation, and fruit qualities. Harnessing various sexual systems (or sex expressions) would derive many applications. We have been
researching on the sex determination systems of persimmon, in which thefirst finding of plant sex determining gene was made, kiwifruit, and white
campion. Their independent but convergent evolution of the sexualities tells
us potentially various ways to artificially modify sex expressions in crop.

Graduate School of Environmental and Life Science, Okayama University65

■ Introduction to Research〓 Research Area : Pomology

Studies on relationship between fruit constituents andits taste
A fruit contains various taste active compounds, such as sugars, organic acids, amino acids,
polyphenols, and aromas. We have been studying to clarify the effects of juice constituents on
the fruit taste and developing quantitative evaluation system for fruit taste.

Studies on the mechanism of gibberellic acid induced
seedlessness in grapes
Gibberellic acid (GA3) is widely used in the production seedless grape in Japan. We have been
studying to clarify the mechanism involved in seedlessness of gibberellic acid treated grapes.

〓 Assoc. Prof.
HIRANO Ken〓 Research Area : Pomology

Effects of timing of flowering on fruit quality and incidence of physiological disorders in peach
We are trying to clarify physiological aspects and mechanisms of various problems or improved
points in high quality fruit production and to develop their solution.
Stability of fruit size and Soluble solid content (SSC) level is important in high quality peach fruit
production. Also, severe flesh disorder causes economic loss. We found that “the fruit from earlytiming of flowering” shows worst qualities and the severe flesh disorder symptom within a tree
awe to inferior accumulationof mineral nutrition and assimilates during the latter halfof fruit development. These
results are utilized to improve
the skill thinned flowers or
fruit.

Researches on detection of incidence of internal fruit physiological disorderand estimation of fruit maturity on the tree using an acoustic vibration method〓 Assoc. Prof.
FUKUDA Fumio

66

To accomplish the stable fruit production, removal ofabnormal fruit in orchard during immature stage andinformation of optimal harvesting was needed. Therefore, it is important to develop nondestructive method
which can be utilized on the tree. By using an acoustic
vibration measurement, split-pit occurrence could be
detected from the ratio of resonant frequencies (f3 / f2),
and progress of fruit maturity (decrease in flesh firmness) could be associated with the decline of f3 value
measured without removal of fruit bag.

〓 Research Area : Vegetable Crop Science

Research on the environmental control for greenhouseproduction using ICT
Greenhouse production is important for
supplying vegetable and ornamental plants.
In our country, the environmental control ingreenhouse using microcomputer has notbeen spread until recently. A controller forenvironmental control was too expensive forsmall scale greenhouse, which was popularin Japan. So, the low cost controller named“Yoshi Max” was developed by our laboratory. This controller is conforms to the Ubiquitous Environment Control System (UECS)
communication protocol (https://uecs.jp/index-e.html). UECS is beginning to spread inJapan as an environmental control systemusing ICT.

〓 Prof.
YASUBA Ken-ichiro〓 Research Area : Control of Flowering

Development of compacted medium using heat fusion fiber

Fig. Medium and leaf
temperature in potless culture.
Medium temperature decreased about 7℃.
Leaf temperature decreased about 2℃.

We found that medium could be hardened using
heat fusion fiber. We demonstrated that use of
hardened medium could enable cell transplants
production and bedding plant production without polyethylene pots. Pansy and garden-type
cyclamen plants grown in compacted medium
without polyethylene pots in the summer season
were bigger than those grown in compacted medium with polyethylene pots. The temperature of
the medium without polyethylene pots was lower than that with polyethylene pots. This could
be due to the evaporative cooling effect from thesurface of compacted medium without polyethylene pots.

Improvement of growth and flowering of Eustoma
grandiflorum by low temperature treatment〓 Prof.
GOTO Tanjuro

It is important to establish a suitable method for rosette avoidance and cost reduction in Eustoma seedlings production insummer. We found that intermittent low temperature storage
treatment could be available as a supplemental method toprevent rosette of Eustoma seedlings after application of low
temperature treatment to imbibed seed. However, suitable temperature and cycle have not been clarified. We confirmed thatthe cycle of 15-15 day stored at 10˚C was a suitable treatment
to avoid rosette, promote growth and decrease labor for Eustoma growing.

Graduate School of Environmental and Life Science, Okayama University67

■ Introduction to Research〓 Research Area : Control of Flowering

Study on the vein structures that increase water transportation in plant decorative organs

Some plant species show characteristic vein structure in decorativefloral organs, development of sclerified parenchyma cells.
The sclerified parenchyma cells increase water transport in decorative organs and flowering longevity on plant or vase life.
We are studying the mechanisms underlying sclerified parenchyma
cell differentiation and trying to use them for increasing the flower
longevity.

A: Flower before the sclerified parenchyma cell differentiation.
B: Flower after the the sclerified parenchyma cell differentiation.

A, C: Vein cells before the sclerified
parenchyma cell differentiation.
B, D: Vein cells after the sclerified
parenchyma cell (SP) differentiation.

Research on flavone synthesis regulation in flower〓 Assoc. Prof.
KITAMURA Yoshikuni

Flower color of a dahlia cultivar, ‘Nessho’.
A: Normal red-colored flower.
B: Orange colored flower of ‘Nessho’.

Plants of a dahlia cultivar ‘Nessho’ produces solid red colored flower from spring to autumn. However, they produce orange colored flower in winter. The color change is owing to the increase in
the flavone accumulation and decrease in the anthocyanidin accumulation.
We are studying the underlying mechanisms of seasonal change of the pigment accumulation.

〓 Research Area : Crop Science

Studies on Salinity Tolerance Relating Grain Productivity in Cereals
An adequate food supply from agricultural crops is essential to the quality of human life. Salinity
is one of the most serious environmental stresses severely limiting crop growth and grain productivity. Salt-affected land occupies about 19.5% of irrigated agricultural land. Rice, a major staple food for the ever-increasing world population, is one of the most salinity-sensitive crops. As
such, improving the salinity tolerance of rice is desired to increase productivity on salt-affectedsoil. However, genetic and physiological knowledge of salinity tolerance relating grain productivity in rice is still limited. We study salinity tolerance in rice at both physiological and molecularlevels. We found several quantitative trait loci (QTLs) for salinity tolerance relating high plant dry
weight and grain yield under long-term saline conditions by using chromosome segment substitution lines carrying segments from a salinity-tolerant variety in the genetic background of a salinity-sensitive variety. Our research advance will contribute to developing rice varieties with highyield under salinity stress conditions.

〓 Prof.
HIRAI Yoshihiko

Varietal difference in salinity tolerance

68

Salinity-induced white head〓 Research Area : Reproductive Physiology

Study on uterine function of cattle under heat stresscondition
Global warming affects agriculture and foodsupply. In livestock industry, extraordinarily
high temperature in summer season gives
stress to livestock species and reduces
their productivity, such as daily gain of bodyweight and milk production.
Recently, it is becoming a big issue thatthe heat stress decrease pregnancy rate ofdairy cows in summer not only in Japan but
also all over the world.

〓 Prof.
KIMURA Koji

To solve this problem, we are investigating theeffect of heat stress on uterine functions of
cattle.
In our current study, it is shown that the heatstress disrupts endocrine function of bovine
uterus such as prostaglandins secretion andinfluences the mechanism for the recognitionof pregnancy in cattle, resulting in low pregnancy rate.
Now we study how the heat stress affect uterine function of cattle.

Immunohistochemistry of bovine endometrium.
Green signals indicate the localization of heatsensor proteins.

〓 Research Area : Reproductive Physiology

Transport systems of gametes and embryo
in mammalian oviducts
Oviduct is an important organ as a site
for sperm capacitation, fertilization andearly embryonic development. It is also
the pathway of gametes and embryo connecting the ovary to the uterus. In spiteof the essential organ for establishmentof pregnancy, regulating mechanisms ofoviductal function are unclear.
Our aim is to clarify the physiologicalmechanisms which control the oviductal
functions.

〓 Assoc. Prof.
YAMAMOTO Yuki

Spontaneous contraction of oviduct is necessary for transport of gametes and embryos,
since it produces peristaltic movement. Oviduct contains endogeneous pulse generator
for contraction called as “pacemaker”. Pacemaker cells generate rhythmic spontaneous
deporalization leading to the contraction ofsmooth muscle cells. In our project, the factors involved in spontaneous contraction areinvestigated using bovine oviductal tissues. In
additon, we also try to identify the pacemakercell in mammalian oviducts.

Graduate School of Environmental and Life Science, Okayama University

69

■ Introduction to Research〓 Research Area : Animal Development and Reproductive Biotechnology

Basic and applied research on mammalian gametes(maturation, fertilization and early development)
We are studying on gametes in mammals including humans during gametogenesis, maturation,
fertilization and early development, to develop efficient systems for embryo production in vitro. We
are also undertaking basic and applied studies to improve the efficiency in the production of morevalue-added useful animals.
Distribution ofphosphodiesterase-5(green) in different
mammalian sperm(right, boar; center,bull; right, mouse)
Intracytoplasmic sperm injection

Development of new systems to produce embryos in vitro〓 Prof.
FUNAHASHI Hiroaki

from oocytes collected from small diameter follicles
For in vitro embryo production in mammals, especially domestic animals, usually oocyte-cumulus complexes derived
from middle follicles with a diameter of 3-6 mm have beenused. However, a large number of small follicles with lessthan 3 mm in diameter, rather than middle follicles, dominantly exist on the surface of ovaries. On the other hand, thedevelopmental competence of the oocytes from small follicles(in meiosis and early development following fertilization) has
been known to be much lower than those from middle follicles. We're trying to make clear the molecular reasons about
differences in the developmental competence and to makeeffort to improve the ability by various modifications.

mtDNA copy number in porcine oocytes

Microinjection of mitochondria〓 Research Area : Animal Development and Reproductive Biotechnology

Basic and applied research on organelles in mammalian oocytes and embryos
Gametes (oocytes and spermatozoa) are highly specialized cells for the transmission of genes to the progeny. Ourlaboratory is interested in understanding the mechanismsof oocyte development, maturation and fertilization in
mammals. Problems in oocyte quality cause the infertility,
and the development of organelles, such as mitochondria
and endoplasmic reticulum, is a key determinant for the
successful fertilization and subsequent embryonic development. We are using several techniques to address theroles of organelles in oocytes including in vitro maturation,
fertilization, genetic manipulation and live cell imaging.
Drp1〓 Assoc. Prof.
WAKAI Takuya

Mito Tracker

Expression of Drp1
protein, which is a criticalfactor associated with thedivision of mitochondria,
in mouse embryos andthe co-distribution withmitochondria
Expression of H2B-mCherry RNA
injected into porcine immature oocyte

70

MergedNormal (right) and sex-reversed
mice (left) by genome editing of Sry.
Both animals had morphologicallynormal uterus and ovaries.

Actin cap in mouse oocyte〓 Research Area : Animal Physiology

Study on sexual differentiation of birds
The sex of animals, including birds, is determined by genes. However, gonads and sexual differentiation of the brain are influenced by hormones and are determined. The mechanism of sex
differentiation in birds differs in many respects because the sex chromosomes are ZW, unlike the
XY type in mammals, and the details are still unknown in many respects. In the gonads, the gene
expression of the enzyme that synthesizes estradiol (aromatase) is overwhelmingly higher infemales than in males, but there is almost no difference in estradiol content between males andfemales. In addition, especially for sexual differentiation in the brain, aromatase gene expression
may be higher in females than in males, and it is possible that sexual differentiation is self-sustaining.

〓 Prof.
SAITO Noboru

Gonadal aromatase gene expression in quail embryos(left) and gonad estradiol content (right).

Expression of aromatase gene in the cerebral
hypothalamus of quail embryos.

〓 Research Area : Animal Physiology

1. Study on host-pathogen relationship and pathophysiology
in parasite infection
We are exposed to the infectious diseases. We need to develop a cheaper, effective, and safety
ways to control the infectious diseases because these incur a heavy economic loss. One of the
problems is that we have a little information to the infectious diseases. Hence, our mission is tounderstand the pathophysiological and immunological mechanisms of infectious diseases. In
near future, we hope that the results of our research are applied to vaccine development and new
strategies for disease control.
Our targets are parasites as follows:
1. Avian coccidia: Our research is to understand 1) the molecularmechanisms of parasite invasion, 2) the pathological mechanisms
in the intestine, and 3) immunological mechanisms.
2. Leishmaniasis: We are studying to understand 1) the molecularmechanisms of disease development, 2) analysis of virulence factorsof the parasites, and 3) the parasitic mechanism.

Eimeria tenella in Cecum

2. Food Science: physiological analysis of food ingredients〓 Assoc. Prof.
HATABU Toshimitsu

Food ingredients have important roles to our health. However, we have a little knowledge ofthem scientifically. Our mission in this research area is to understand the physiological effects offood ingredients, especially polyphenols
and carotenoids,
and to develop theinnovative and useful way for humanand animal health.

Graduate School of Environmental and Life Science, Okayama University71

■ Introduction to Research〓 Research Area : Animal Breeding and Genetics

Genetic parameters for calf mortality in JapaneseBlack cattle
The Japanese Black cattle is the predominant beef breedin Japan. In Japan, calves are sold at action, so, the deathof calves is an economic loss for the reproductive farm. In
spite of the economic importance of calf mortality, studies of
the genetic parameters of calf mortality are few. Because,
calf mortality is not a continuous trait such as body weight,
but a threshold trait, classified only as live or dead. However, in recent years, the genetic parameters of thresholdtraits can be analyzed. Therefore, we investigate the genetic parameters of calf mortality in Japanese Black cattle.

Genetic parameters for reproduction traits in JapaneseBlack cattle
In recent years, Japanese Black cattle have been
selected mainly for their meat quality, especiallythe degree of (intramuscular) marbling. In practice, genetic improvement for meat quality is veryhigh. On the other hand, fertility performance isfalling. Therefore, it is very important for genetic
improvement of fertility performance to investigate
the genetic parameters for reproduction traits
and the genetic correlation between reproduction
traits and carcass traits in Japanese Black cattle.
Moreover, we investigate the genes responsible
for reproduction traits with another institute.

〓 Assoc. Prof.
IBI Takayuki〓 Research Area : Animal Nutrition and Feed Science

Health promotion and disease prevention of animals
Mastitis, an inflammation of the mammary gland regarded as the most important disease affecting
dairy herds, is triggered by pathogens derived
from infectious and environmental bacteria.
Milk microbiota is shown to be influenced by
the microbiota present on teat skin, bedding,feed, and in the surrounding air. Region, season, and hygiene of the milking practices also
influence the microbiota. We characterize themicrobiota of the gut, milk, and cowshed environment to gain insights into improved cow
management and mastitis prevention.

Integrating genomic approaches to upgrade the value ofdairy products〓 Prof.
NISHINO Naoki

72

Various projects have been progressed to improve the productivity of dairy cows and the value ofdairy products using genomic approaches. Hiruzen,a northern region of Okayama Prefecture, is a wellknown area where dairy farming performs with Jersey cows. Jersey milk has a rich taste and high-fat
content, making it suitable for the production of dairy
products such as butter, cheese, and yogurt. β-casein
is one of six milk proteins produced by the CSN2
gene, and the variants can be classified into A1 andA2. We identify the CSN2 gene variants and evaluate
the quality and function of A1 and A2 milk products
using rodent models.

〓 Research Area : Animal Nutrition and Feed Science

Research of the mechanism by which food microorganisms anddietary fiber intake prevent and improve obesity-related disorders
Excess energy intake and lack of exercise not only cause obesity, but various lifestyle-relateddiseases caused by obesity. Although correction of lifestyle is the most important to prevent andimprove them, intake of food microorganisms and dietary fiber is effective as an additional preventive measure. In our laboratory, we are searching for new food microorganisms and dietaryfibers that prevent and improve obesity-related disorders, and we are also studying how thesefood materials act on gut microbiota and gut immune system to exert their effects.

Effect of fat and oil intake on gut microbiota andimmune system〓 Assoc. Prof.
TSURUTA Takeshi

We daily consume a variety of fats and oils such as lard, beef fat, and vegetable oil. The fatty
acid composition of these fats and oils differs greatly, which affects the physiological effects ofeach fat and oil. In our laboratory, we evaluate the effect of type of fats and oils and their intake
amount on gut microbiota composition, secretion of immunoglobulin A (IgA), a major molecule
responsible for gut immune system, and the IgA reactivity to gut microbiota.

〓 Research Area : Animal Applied Microbiology

Study on human gut microbiota to contributefor health
1. Research history and analytical methods of gut microbiota
2. Gut microbiota and the bacterial composition and diversityof human gut microbiota
3. Symbiosis with the host of the gut microbiota
4. Effect of food ingredients on the human gut microbiota
5. Gut microbiota and disease (effect of gut microbiota to host)
6. Metagenome analysis and gene function of gut microbiota

Research on probiotics/prebiotics effects and complete
genome analysis of lactic acid bacteria and bifidobacteria
1. Complete genome analysis of lactic acid bacteria andbifodobacteria
2. Functional bacterial genome analysis
3. Research on probiotics/prebiotics effects by using
gnotobiotic mice
4. Effect of dietary fiber as prebiotics〓 Prof.
MORITA Hidetoshi
A scanning electron microscope(SEM) photograph of this lactic acidbacterium whose complete genome
was analyzed by me.

Graduate School of Environmental and Life Science, Okayama University73

■ Introduction to Research〓 Research Area : Animal Applied Microbiology

Studies on protein metabolism of lactic acid bacteria
Lactic acid bacteria (LAB) are known as fastidious microorganisms that require a wide variety ofexogenous free amino acids or peptides as nitrogen sources for growth. Most of Food stuffs suchas milk generally contain proteins but very low amount of free amino acids and peptides. Therefore, LAB first hydrolyze the proteins to get nutritious oligopeptides using their own cell-envelope
proteinases (CEP). The oligopeptides released are subsequently taken up by the LAB cells via
specific transport systems for further degradation into shorter peptides and free amino acids
using various intracellular peptidases. The CEP, transporters and peptidases are species- or
strain-specific, and their functional and enzymatic differences are an important factor to produce
the diversity on taste, flavor and health-promoting effect of fermented food products. In our laboratory, we are studying the protein metabolism of LAB; particularly focusing on characterizationof CEP and function of the oligopeptides released by CEP on fermented foods.

Studies on antimicrobial substances produced bylactic acid bacteria〓 Assoc. Prof.
ARAKAWA Kensuke

Lactic acid bacteria (LAB) are known as safe producers of antimicrobial substances such aslactic acid and bacteriocins. Bacteriocins, ribosomally biosynthesized antibacterial peptides,
have strong activity with a very small quantity and are easily degraded by digestive enzymes in
the animal gut. Food-derived antimicrobial peptides are also produced by LAB. Food proteinssuch as milk caseins are good origins of functional peptides, including with antimicrobial activity, released by hydrolysis using cell-envelope proteinases (CEP) of LAB. These antimicrobial
peptides are expected to be used as a safe natural preservative (biopreservative) for foods andfeeds. In our laboratory, we isolated some LAB strains with bacteriocin productivity and high
CEP activity for production of food-derived antimicrobial peptides, and characterized the bacteriocins and the food-derived antimicrobial peptides for application to foods and feeds.

〓 Research Area : Assisted Reproductive Medicine

The meiotic abnormalities in mouse and humanoocytes and their mechanisms
During the maturation process of human oocytes, numerous genes are responsible for meiosis. Recent studies
have begun to reveal that defects in some interrelated genes are the cause of female infertility. We aim to perform functional analyses of the process of oogenesis, during the first and second meiosis using oocytes frommutant mice, which present with a mutation, leading to genetically developed abnormalities on chromosomal
crossing-over during meiosis. In this way, we hope to contribute to the existing body of therapeutic strategies and preventive measures which can be taken against human infertility.
As ten to twenty percent of cases of infertility are considered
to be idiopathic, we also aim to perform a comprehensive
analysis of meiotic DNA mutations and thereby elucidate thecauses of infertility derived from those mutations.

The elucidation of the mechanism of dysmorphic phenotypes in humanoocytes and preventive measures against those dysmorphisms〓 Assoc. Prof.
OTSUKI Junko

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The dysmorphic phenotypes to be found in human oocytes are unlike any other species, with the exception of chimpanzee oocytes. Among these dysmorphisms, we have been focusing on two phenotypes:
smooth endoplasmic reticulum clusters (sERCs) and refractile/lipofuscin bodies. We have found that theincidence of mitotic and meiotic cleavage failure during the second polar
body extrusion is significantly higher in oocytes with sERCs than that in
oocytes without sERCs. Regarding the refractile body (RB), we have reported that it presents with autofluorescence. Viewed by means of transmitted electron microscopy, the refractile bodies display the conventional
morphology of lipofuscin inclusions and consist of a mixture of lipids anddense granule materials. We aim to elucidate the mechanisms of thesedysmorphic phenotypes in human oocytes and work towards preventive
measures against them.

〓 Research Area : Assisted Reproductive Medicine

Research on the Mechanism of Oocyte Development
The mammalian ovary contains follicles in many development stages, which can be grown in vitro
to provide an additional source of mature oocytes. These processes have long periods and the development and differentiation of female germ cells require a
unique microenvironment created by surrounding somatic
cells. Our research theme is focused on the mechanism ofoogenesis/folliculogenesis by somatic cells in human andanimal ovaries. Furthermore, we are developing in vitro culture systems compatible with all stages of oocytes present
in ovarian tissue. These systems contributed to assisted
reproductive medicine, animal reproduction, and the conservation of endangered species.

Cryopreservation System of Reproductive Tissue andGerm Cell〓 Asst. Prof.
TASAKI Hidetaka

Embryo cryopreservation has become routine procedures in assisted reproductive medicine
worldwide. Recently, there has been a growing interest in cryopreservation of ovaries or oocytes
for women's career development and to protect germ cells fromcancer treatment. A few reports successful in births by obtaining
mature oocytes from the frozen ovarian tissue or immature oocytes. However, the success rates are limited, the optimizationof these freezing methods is urgently needed. To solve this problem, we investigated the effects of cryopreservation on ovariantissue and oocytes. We focused on cryoprotective substances,osmotic stress, and antioxidants during the freeze-thaw process.
Our research goal is to establish safe cryopreservation methods,
which technology will also preserve livestock and wildlife in theevent of unprecedented epidemiological problems.

Graduate School of Environmental and Life Science, Okayama University

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