bluuebunny/crossref_metadata_2025 huggingface dataset:
Management Strategies to Protect Coastal Areas from Oil-Polluted Seawater (A Case Study of Coastal Areas in Bekasi Regency)
Authors: Agustine P , Parung H , Davey P , Frid C
Published: December 2021

Following an oil spill in the western Java Sea, in July 2019, the issue of oil pollution has received heightened interest. More and more people in Indonesia are increasingly aware that environmental damage will be a severe threat to the sustainability of ecosystems and environmental services. Given that oil pollution does endanger not only the aquatic ecosystem but also the surrounding terrestrial ecosystem, it is essential to encourage the involvement of stakeholders to contribute to efforts to prevent and minimize the impact of oil pollution in coastal areas that may arise in the future. Thus, since oil pollution is extremely harmful not only to aquatic ecosystems but also terrestrial ecosystems, coastal management strategies are urgently required to minimize the impact of oil pollution in the future. The overall aim of this research is to provide recommendations for policy formulations that may be adopted by the relevant local government to protect coastal areas from seawater contaminated with oil. This research uses both qualitative and quantitative approaches, including Statistical analysis, Strength-Weakness-Opportunity-Threat (SWOT) analysis and Analytical Hierarchy Process (AHP). The type of data collected will be primary data and secondary data which are sourced from experts and agencies engaged in the management of the coastal and marine environments.
Interactions of Growth Environmental and Application of GA3 Concentration On Shallot Productivity
Authors: Handayani A R , Syam’un E , Ulfa F
Published: December 2021

The purpose of this study was to evaluate the combination of technology using GA3 and agro-climate-based growing environment to increase shallot production in the lowlands. The study was designed with a nested factorial design, where the replicates were nested in an agro-climatic environment. The growing environment used consists of three conditions, namely open nature (e1), screen house (e2), UV plastic (e3). Meanwhile, the GA3 concentration (g) factor used consists of 4 levels, namely 0 ppm (g0), 100 ppm (g1), 200 ppm (g2) and 300 ppm (g3). This research design will be repeated 3 times for each treatment, so that the total experimental plot is 36 experimental units. The characters observed consisted of six characters, namely the number of leaves, absorption, reflection, tuber fresh weight, tuber diameter and tuber production. The results of this study indicate that GA3 treatment and UV application are very influential in increasing the productivity of shallots. The combination of 200 ppm GA3 concentration with the use of UV is the recommended technology in shallot cultivation. The fresh weight character of the tuber is a recommended secondary character in evaluating the potential of shallot cultivation technology. Hasanuddin University, Jl. Perintis Kemerdekaan No. KM.10, Tamalanrea Indah, Kec. Tamalanrea, Kota Makassar, Sulawesi Selatan 90245.
Analysis mixed characterization of Kalimantan coal and mangrove wood charcoal character as briquette raw material
Authors: Rahman R , Azikin B , Tahir D , Widodo S
Published: December 2021

This study using three types of coal from East Kalimantan and South Sulawesi Mangrove Wood Charcoal which consisted of various compositions. In sample analysis using analysis, namely: proximate, ultimate, and calorific value. Proximate analysis: ash content, volatile matter, moisture content, fixed carbon; ultimate analysis: carbon and sulfur content and the calorific value using the bomb calorimeter method. The results of the proximate analysis showed that the fixed carbon content was obtained in the mixture of MWC 75% + KJA 25% = 52.45%, while the lowest was obtained at IC 100% = 32.86%; The highest volatile matter was obtained at KJA 100% = 44.23%, the lowest was at MWC 75% + KJA 25% = 31.90%, the highest ash content was IC 100% = 9.14% the lowest was at MWC 75% + KJA 25% = 5.94% and the highest moisture content was seen at IC 100% = 15.17% but MWC 75% + IC 25% = 9.52%. The results of the ultimate analysis showed that the lowest sulfur content was in the mixed variation of MWC 75% + KJA 25% = 0.168%, while the highest sulfur content was obtained at IC 100% = 0.874%. However, it was still in the low sulfur category <1. The highest calorific value is obtained by varying the composition at MWC 75% + IC 25% = 5919 cal/gram, while the lowest was obtained at KJA 100% = 4913 cal/gram. So based on this research, the addition of mangrove charcoal is very good for increasing the calorific value.
Multi-Disaster Management Strategy in Indonesia
Authors: Maulana A
Published: December 2021

Managing natural disasters amid the Covid-19 pandemic needs a special strategic approach. Indonesia, as a natural disaster-prone country, is now facing a problem due to areas with high vulnerability and a lack of disaster literacy. A multi-disaster e.g., the occurrence of natural disasters in the middle of Covid-19) management strategy is badly needed to face up to this situation. This paper offers a multi-disaster management strategy based on empirical experience as a reference for stakeholders, especially government at all levels. Five strategies are offered to overcome the impacts of a multi-disaster event, especially in natural disaster-prone areas with high Covid-19 case rates. Strengthening government institutions is the first priority to be addressed as coordination among government at all levels (from central to regency and city governments) will minimize the casualties. Logistic and infrastructure arrangements should be well managed to avoid any panic and chaos during multi-disasters. Recruitment of volunteers could be very helpful during the emergency response stage. Provision of evacuation sites and temporary shelters that meet the Covid-19 requirements is a must to prevent virus spread during evacuation and emergency response stages. Last but not least, increasing individual disaster literacy should be considered an essential component of a multi-disaster management strategy. Finally, well-managed coordination between all stakeholders is paramount, especially in natural disaster-prone areas with a high level of Covid-19 spread.
Rainwater Harvesting to Increase Freshwater Carrying Capacity on Small Islands (A Case Study of Pramuka Island)
Authors: Girdayanto P , Davey P , Munir A
Published: December 2021

Pramuka Island is a small island that is covered with dense settlements, inhabited by 1,715 people, and experiencing rapid population growth with increasing visits by tourists every year ]. As a result, there is a high demand for freshwater, leading to a large-scale exploitation of groundwater on the island. Yet, a research conducted by [1] had indicated that groundwater on Pramuka Island is below the minimum standards for drinking water. This report discusses the effectivity of a rainwater harvesting system as a solution to the freshwater carrying capacity of Pramuka Island. The discussion involves analysis of freshwater carrying capacity based on water balance calculations between freshwater supply with rainwater harvesting and potential freshwater demands for domestic usage, tourism, and other activities. The results revealed that the scenario of the whole island as a rainwater catchment area is enough to supply local freshwater demand for approximately 27 years.
Evaluation of potential liquefaction based on Cone Penetration Test (CPT) data
Authors: Amaliah R , Harianto T , Muhiddin A B
Published: December 2021

An earthquake can inflict a liquefaction hazards which can damage buildings and infrastructure. Furthermore, earthquakes are difficult to predict when and where earthquakes will occur and happen suddenly without being preceded by signs. Therefore, we must do a geological investigation before building a construction to evaluate the potential liquefaction in that area. Evaluation of the potential liquefaction using Cone Penetration Test (CPT) is one method can be used because repeatable, provided a continuous profile, and economic. This method needs peak ground acceleration (amax) value at an interval of 0.1 g to 0.6 g and earthquake magnitude of 6.2 scale richter. Based on the results of the research was obtained in this research area, there were potential liquefactions when the peak ground acceleration (amax) value was above 0.3 g.
Permeability Measurement of Hot Mix Cold Laid Containing Asbuton as Porous Asphalt
Authors: Tumpu M , Gusty S , Tjaronge M W , Parung H
Published: December 2021

Porous asphalt is a pavement layer structure with aggregate gradations with a coarse fraction greater than 70-85% of the total weight of the mixture so that the resulting structure is more open and porous, which prevents water from stagnating on the road surface reduces water splash and makes the road less slippery. This study aims to analyze the permeability properties of a mixture of hot mix cold laid containing Asbuton in the form of porous asphalt. The research used was an experimental laboratory method. This study used Buton granular asphalt (Buton granular asphalt) with variations in BGA content of 4.5%, 5%, 5.5%, 6%, and 6.5%. The use of BGA is aimed at improving the performance of porous asphalt mixtures without using oiled asphalt. Manufacture of test objects through permeability tests. The results showed that the permeability value for the BGA content of 4.5% was 0.05 cm/s, the BGA content of 5% was 0.06 cm/s, the BGA content of 5.5% was 0.06 cm/s, the BGA content was 6%. is 0.03 cm/s and the BGA content of 6.5% is 0.02 cm/s.
Volumetric Characteristics of HRS-WC Mixed Using Petroleum Bitumen Grade 60/70 as Binder
Authors: Irianto  , Tumpu M , Parung H
Published: December 2021

This study aims to determine the volumetric values consisting of VIM, VMA and VFB on the binder layer mixture using HRS-WC gradation using petroleum bitumen as a binder. The method used in this research is experimental method in laboratory. In this study, variations of asphalt content used were 5.5%, 6.0%, 6.5%, 7.0% dan 7.5%. These variations were obtained from the calculation of effective asphalt level of 5.9%. The results show that the VIM values decreases along with the increase of bitumen content used. VIM values obtained were 6.69%, 5.82%, 5.18%, 4.42% and 3.34%, respectively. The VMA values obtained were 18.12%, 18.38%, 18.84%, 19.21% and 19.30% for each bitumen content. Besides that, the value of VFB is also taken into account and the values obtained for each quality of bitumen content are 63.10%, 68.41%, 72.57%, 76.99% and 82.71%.
The Effect of Loading Rate on Fracture Toughness of Concrete using Type I Fracture Toughness Test Flattened Brazilian Disc (FBD) Mode
Authors: Yaqin A , Djamaluddin  , Qaidahiyani N F
Published: December 2021

Mining activities in open pit and underground mines will always be associated with rock breaking or stripping activities (both mechanical and blasting), so that this can affect the structure and strength of rocks. The strength of the rock is strongly influenced by the presence of initial cracks (pre-existing cracks) and rock anisotropy conditions associated with discontinuous plane conditions. Fracture mechanics is a science that illustrates how a fracture can occur and propagate during applied stress on material. The main parameter in fracture mechanics is called fracture toughness which shows the resistance of the material to propagate the crack. There are several mode in determining type I fracture toughness, one of which is type I fracture toughness Flattened Brazilian Disc (FBD) mode. Type I fracture toughness test is carried out using a compression machine in a laboratory and is conducted on concrete samples consisting of 3 (three) various samples, with a ratio of cement and sand composition of 1:1, 1:2, and 2:1. This test also uses different loading rate values, namely 2.50 mm/min, 2.70 mm/min, and 2.83 mm/min. The results of the type I fracture toughness value from each loading rate will be compared to determine the effect of the loading rate on the value of type I fracture toughness. The obtained fracture toughness value is also related to the physical and mechanical properties of the samples. Based on the results of tests, it can be seen that the loading rate affects the value of fracture toughness, the increase in fracture toughness value is followed by the higher loading rate. In addition, it can be seen that the fracture toughness value is directly proportional to the uniaxial compressive strength value and the indirect tensile strength value. The average correlation value obtained is R2 = 0.9884 (indicating a strong relationship).
Spatial Mapping of Aedes Sp. Densities and Endemicity Level of Dengue in Three Villages in South Sulawesi, Indonesia
Authors: Ishak H , Mallongi A , Birawida A B , Syahribulan
Published: December 2021

The study aim to analyze the spatial map of the density ofAedessp., several measurement methods, and the relationship between environmental factors with mosquito density in Makassar City, Maros and Gowa Cities. The research method used an ecological study design. In this study, surveys of larvae, ovitrap and Lighttrap were be used to measure the density ofAedessp. Data processing using SPSS version 22 and Arview GIS 10.5. The results that spatial analysis showed a random pattern or spread of density of larvae, ovitrap and adult mosquitoes. the Larva and Ovitrap survey methods were specific measured the density of Dengue vectors (larvae, eggs and adult mosquitoesAedes aegypti) while the Light Trap method was not specific. There was a significant relationship between temperature, humidity and egg density andAedes aegyptimosquitoes in three DHF endemic sub-districts; except humidity and mosquito density was not significant in Bontoa Village of Maros Regency (p> 0.05). There was no significant relationship between the wire netted ventilation factor and the density ofAedes aegyptimosquitoes in the three DHF endemic sub-districts except for the mosquito density there was a significant relationship in Bontoa Village, Maros Regency.
Application of Bacillus subtilis on red onion (Allium ascalonicum)
Authors: Gau A D T , Syam’un E , Ulfa F
Published: December 2021

The increase of public consumption of red onion urge the increased production in order to meet consumer needs. To increase red onion production, it is necessary to formulate cheap and easy technology. This study aims to examine the effect of Bacillus subtilis on the growth and production of red onion (Allium ascalonicum). The research was conducted at the Laboratory of Plant Diseases, Department of Plant Pests and Diseases and Experimental Fam Land, Faculty of Agriculture, Hasanuddin University Makassar. The study was conducted from February to April 2020. 80-days old red onion were treated with Bacillus subtilis bacteria consisting of 4 levels, namely control (p0), 104 density (p1), 108 density (p2), and 1012 density (p3). The results showed that the application of Bacillus subtilis affected the number of leaves, number of stems (tillers), number of bulbs, bulbs diameter (mm), and bulbs wet weight per plant (grams) with the best treatment at a density of 108 (p2). The rate of sprouting was not affected by the application of Bacillus subtilis.
Marketing Efficiency In Rice Commodity Supply Chain Management In Kalukku District, West Sulawesi Province
Authors: Said S A , Darma R , Tenriawaru A N
Published: December 2021

The market performance measure that is often used is efficiency in marketing. Marketing efficiency can be improved by applying the concept of supply chain management in agriculture. This study aims to analyze the efficiency of marketing in rice supply chain management. The research was conducted in August 2018 in Kalukku District, Mamuju Regency. The sampling method was carried out by purposive sampling, obtained as many as 8 farmers with the criteria of owner or confinement farmers who have farming experience and several farmers who serve as heads and members of farmer groups, where information on farmers, it is known that the flow of products that involve other marketing agencies is also used. respondents in this study were determined by snowball sampling. Data analysis used is marketing efficiency analysis. The results showed that there were 3 rice marketing channels in Kalukku District, Mamuju Regency. The marketing channel has been efficient, where in supply chain channel 1 with an efficiency level of 12.9%, on marketing channel 2 with an efficiency level of 12.2%, and marketing channel 3 with an efficiency level of 13.2%.
The Potential of Hydro Renewable Energy Technology to Electricity Remote Villages in Papua and Maluku Islands, Indonesia
Authors: Sudibyo H , Pikra G , Fudholi A
Published: December 2021

The islands of Papua and Maluku are eastern Indonesia which consists of remote islands and villages. The Papua Islands consist of 3,749 islands divided into two provinces, namely Papua and West Papua, while the Maluku Islands are 1,735 islands into two provinces of Maluku and North Maluku, the number of inhabited islands in Papua and Maluku around 230 islands and around 100 newly electrified islands. The electrification ratio for Papua is 47.69%, West Papua is 89.94%, Maluku is 87.02% and North Maluku is 88.68%. The electrification ratio is still below the national average. Maluku Islands and Papua Indonesia has abundant renewable energy natural resources, namely hydro potential. The total hydro energy potential of Papua and Maluku is 808 MW. To overcome this shortage of electricity, it is necessary to develop a renewable energy generation system according to the potential of the area, namely hydro power. Energy generation technology that is environmentally friendly, efficient, effective, and reliable can be a solution for electrification in Papua and Maluku. Hydro power plants using vortex turbines, picohydro turbines and axial turbines for permanent magnet generators can be a solution to electrify areas or villages remote in Papua and Maluku.
Solar Tracker and Wind Guide Designs to Improve the Energy Conversion in a Hybrid Energy Harvester System
Authors: Ekawati Estiyanti , Gita Putra Gusnul Andria , Reza Muhammad Fahrur , Budi Eko Mursito
Published: December 2021

This study focused on improving the energy conversion of hybrid solar panels and a wind turbine system. The improvement was produced by enhancing the system with a solar tracker and a wind guide. A microcontroller operated the single-axis solar tracker based on a solar elevation database at -6.91N, 107.61E. The wind guide was an Omni Directional Guide Vane (ODGV), designed to support the drag-type Savonius turbine. The ODGV’s inside and outside diameters were 540 mm and 1000 mm, respectively. The wind guide had a 30° polar angle between fins and produced a torque of 0.128 Nm at a wind speed of 4 m/s. The solar tracker increased the system performance by 47% and the wind guide by 166%.
Modeling Radiation Exposure from Normal Release of 137Cs Radionuclide to Groundwater for Post-Closure Assessment of Serpong Near Surface Disposal Demo Facility
Authors: Anggraini Zeni , Rachmadetin Jaka , Shadrina Nazhira , Sucipta Sucipta , Sriwahyuni Heru
Published: December 2021

Near-surface disposal (NSD) has been applied in several countries to dispose of low-level radioactive waste. The demo plant of this disposal type is planned to be constructed in Serpong Nuclear Area, Banten. An assessment of radiation exposure is necessary to ensure the safety requirement of the facility in order to support this program. This study aims to estimate radionuclide migration from the proposed NSD demo facility to the environment and the corresponding total human dose using AMBER mathematical modeling. The representative radionuclide,137Cs, was selected because of its high mobility in the environment and the relatively long half-life in the low-level waste inventory. The scenario considered in the modeling was the normal release to the environment through groundwater. Parameters such as initial radionuclide concentration, soil physical parameters of the study site, and disposal design were entered into AMBER software to be calculated using mathematical formulas. The results show that the radionuclide concentration value in the environment is below the safe limit recommended by the Environmental Supervisory Agency. Likewise, the maximum dose received by the community around the facility is 7.40×10-11 mSv/y, 550 years after the post-closure of the facility, which is also below the regulatory limit of 1 mSv/y for the public.
Solar Irrigation System in Indonesia: Practical Assessment and Evaluation for Converting Fossil Fuels with Solar Energy
Authors: Aini Zulfatri , Kunaifi  , Wenda Alex , Ismaredah Ewi , Anjarjati Wahyu
Published: December 2021

This study proposes a sustainable solar-powered irrigation system (SPIS) for a 75-hectares rice farm in Krandegan Village, Purworejo Regency, Indonesia. The existing water pumping system uses diesel engines which cost around Rp. 200 million per year that cannot be provided by the farmers. The SPIS was designed based on water requirements calculated according to the Food and Agriculture Organization (FAO). The technical design of SPIS used Lorentz Compass considering local solar energy sources and the availability of SPIS components in the local markets. The entire farm in Krandegan requires 11 SPISs with a total capacity of the solar panel of 20.8 kWp. Also, the SPISs use 11 centrifugal DC pumps; 10 surface and 1 submersible type. The SPIS in Krandegan would require a total cost of Rp. 1.29 billion. Without the financial support of the capital costs from other parties, the simple payback time (SPT) would be around 6.5 years, which is good for a solar photovoltaic (PV) project. SPIS is not only a viable solution to replace diesel engines in supplying water to the rice farm in Krandegan, but is also in line with the seventh target of Indonesia’s Village sustainable development goals (SDGs).
Effect of organic substrate type in electricity production from microbial fuel cell (MFC) inoculated by Staphylococcus saprophyticus ICBB 9554
Authors: Khoirunnisa NS , Anwar S , Sudadi U , Santosa DA
Published: December 2021

Microbial Fuel Cells (MFCs) are bioelectrochemical devices that can directly transform the chemical energy from organic matter into electrical energy using microbial metabolic activity, so microbes play an essential role. This study explores some organic substrate alternative cost-effective for Staphylococcus saprophyticus ICBB 9554 as an exoelectrogen for electricity production in MFCs. The organic substrates that were chosen were sugar, molasses, and palm sugar. The best performance in electricity production was in molasses which showed output voltage, electrical current, and power density of 789 mV, 0.48 mA, and 68 mW/m2, respectively. The COD removal, Coulombic efficiency, and bacterial density in molasses also the highest that was about 68.18 ± 0.00%, 45.80 ± 2.17%, and 1.09×108 cfu/ml, respectively. Molasses is a potentially cost-effective alternative organic substrate for MFCs inoculated by Staphylococcus saprophyticus ICBB 9554.
The Effect of Temperature on Solvent Recycle Process using Stripping of CO2 from MDEA, Ethylene Glycol, and Water
Authors: Mindaryani Aswati , Rahayuningsih Edia , Wijayanto Nikodemus Bambang , Masulili Alwan Naufal
Published: December 2021

Stripping is a process to separate dissolved gas in the saturated solvent to regenerate the absorption solvent. In this study, N2 gas was used to strip dissolved CO2 gas in MDEA, ethylene glycol, and water. The experiment was conducted with three variations of temperature, namely 28°C, 35°C, and 50°C, to determine the effect of solvent’s temperature entering the stripper column on the value of the mass transfer coefficient (Kla). The stripper effluent was connected to the KANE 457 Flue Gas Analyzer to measure the concentration of CO2. Data retrievals were carried out at the 0; 30; 60; 90; 120; 150; 180th second. The experimental results show the trend of mass transfer coefficient of CO2 (Kla) is higher with the increase of solvent’s temperature entering the stripper.
Design of a Photovoltaics Stand-Alone System for a Residential Load in Bunaken Island Using HOMER
Authors: Rumbayan Meita , Sompie Sherwin R U , Ruindungan Dirko G S , Panjaitan Naomi V
Published: December 2021

The purpose of this study is to design a Photovoltaics (PV) stand-alone system for a residential load in Bunaken Island using HOMER (Hybrid Optimization of Multiple Energy Resources). Bunaken Island, the case study location, is a popular tourist spot in North Sulawesi, Indonesia. This island is facing the issue of limited access to electrical energy from the grid. The design and techno-economic analysis in Bunaken island leveraged HOMER software. This software was developed by National Renewable Energy Laboratory (NREL). Furthermore, the results suggested that the techno-economical PV stand-alone system in Bunaken Island could be developed as alternative energy to support electricity as energy security issued for Indonesia.
Stator flux barriers to improving interior permanent magnet motor characteristics
Authors: Irasari P , Widiyanto P
Published: December 2021

There are many methods to improve the characteristics of permanent magnet motors. One of them is by making flux barriers on the stator or rotor, or both. This paper discusses the adding stator flux barriers on the rectangular-shaped stator of the interior permanent magnet motor. The purpose is to increase the maximum rotation of the machine. The shape of the flux barrier is circular considering the ease of the manufacturing process, with the proposed diameter is one slot pitch. Several diameters of larger and smaller sizes will also be simulated for comparison. Other parameters, which are cogging torque and stator core loss, are also investigated. Design and simulation are carried out analytically and numerically using 2D finite element analysis. The simulation results indicate that the proposed flux barrier diameter can provide the maximum rotation with only a tiny decrease in output torque. In this regard, it can be concluded that the stator flux barriers affect the speed than output torque. Additional advantages are also obtained from the decrease in cogging torque and core loss at the base speed compared to a stator without flux barriers.
Radioactive Fission Waste from Molybdenum-99 Production and Proliferation Risks
Authors: Aisyah  , Artiani Pungky Ayu , Rachmadetin Jaka
Published: December 2021

Molybdenum-99 (99Mo) is a parent radioisotope of Technetium-99m (99mTc) widely used in nuclear diagnostics. The production of this radioisotope by PT. INUKI generated radioactive fission waste (RFW) that theoretically contains239Pu and235U, posing a nuclear proliferation risk. This paper discusses the determination of radionuclides inventory in the RFW and the proposed strategy for its management. The radionuclides inventory in the RFW was calculated using ORIGEN 2.1 code. The input parameters were obtained from one batch of 99Mo production using high enriched uranium in PT. INUKI. The result showed that the RFW contained activation products, actinides, and fission products, including239Pu and235U. This result was then used for consideration of the management of the RFW. The concentration of 235U was reduced by a down-blending method. The proposed strategy to further manage the down-blended RFW was converting it to U3O8 solid form, placed in a canister, and eventually stored in the interim storage for high-level waste located in The Radioactive Waste Technology Center.
Improving the Electrochemical Performances of Supercapacitors through Modification of the Particle Size Distribution of the Carbon Electrode
Authors: Sutarsis  , Chang Jeng-Kuei
Published: December 2021

The effect of a synergetic mixture of large and small activated carbon composite particles on the performance of organic electrolyte-based EDLCs was examined in this work. Different surface areas, pore volumes, particle size distributions, and concentrations of surface functional groups were observed in bi-modal particle sizes of activated carbon composites. Using galvanostatic cycling, the cell capacitance of an activated carbon composite rose with an increase in the fraction of big particles (C8) over a wide range of rates. Due to their moderate specific surface areas, a relatively low fraction of smaller particle size, low concentration of oxygen functional groups, low contact resistance, and high ionic conductivity, the 0.25C4+0.75C8 carbon electrode composite has a high specific capacitance, high retention of high rate discharge, and long cycle life when compared to other composites and single carbon electrodes (C4, C8, and C12). The leakage current and gas evolution may be suppressed to an operating voltage of 3.0 V with an appropriate fraction of large and small particle composition on the carbon electrode, boosting the carbon cells’ reliability and stability.
Improved direct lysis PCR amplification method of microalgal culture for sequencing and species identification
Authors: Fitriyah F , Faramitha Y , Sari D A , Kresnawaty I , Panji T , Santoso D
Published: December 2021

Molecular approach plays important role in species identification for microalgae which involves sequencing of specific DNA barcode present in the genome. This approach involved preparation of template DNA for polymerase chain reaction (PCR) which is time consuming and requires large amounts of algal cells. Microalgal direct PCR have been used frequently for species identification, which simplified the DNA isolation procedure. However, the recent attempts to amplify the rbcL gene of microalga using the previously reported protocol led to poor repeatability. In this study, Nannochloropsis gaditana NIES-2587 was cultured in f/2 liquid medium. The culture growth was estimated on optical density value and the lysis process was improved using gradual temperature procedure during the PCR process. The same culture was extracted using manual DNA extraction method for comparison. The DNA obtained from both methods were amplified using RbclN primer pair to amplify 1486 bp partial sequence of Nannochloropsis rbcL gene, followed by the sequencing of the PCR product. Molecular identification based on the sequence result and BLAST analysis indicated that direct PCR and manual DNA extraction methods successfully produced high sequences result and confirmed the identity of microalgae species into N. gaditana strain CCMP527 with a genetic similarity of >99%.
The unusual sclerotium of Rhizopogon roseolus reported from pure cultures
Authors: Putra P , Hermawan R , Aimi T , Shimomura N
Published: December 2021

During the assessment of mycelial cords of Rhizopogon roseolus on poor nutrient of Modified Melin-Norkrans (MMN) medium, we found some sclerotia produced on the surface of extraradical mycelia. The sclerotia were 0.27 mm in average of diameter and produced after 2 months of incubation. The current knowledge defined the sclerotium as mass of hyphae and normally having no spores in or on it. However, we found and suspected the small structures like spores (1-1.5 um) inside the sclerotium. These structures were ellipsoid, hyaline, with the smooth surface. We then incubated the sclerotium and these small structures on TM7 detecting medium whether they can produced the secondary mycelia of R. Roseolus, but no germination was observed. Interestingly, the bacterial colonies which connected to hyphae of sclerotium were appeared. The colonies were transferred to Luria agar (LA) medium. The morphological observation of bacterial cells from TM7 and LA confirmed that they were the same as small structures inside the sclerotium. This is the first report on production of unusual sclerotium of R. roseolus in pure cultures. Further study is required to reveal the role of bacteria on production of sclerotium of R. Roseolus.
A new report of three parasitoids of the cogongrass gall-midge Orseolia javanica Kieffer & Van Leeuwen-Reijnvaan (Diptera: Cecidomyiidae) in Bogor West Java
Authors: Maqalina M N , Harahap I S , Hidayat P
Published: December 2021

The cogongrass gall midge, Orseolia javanica, has been identified as a biological control agent with the ability to specifically attack cogongrass (Imperata cylindrica) or known in Indonesia as alang-alang. However, in the field, the cogongrass gall midge has a high parasitism by insect parasitoids, which could lead to population collapse. Information regarding the insect parasitoids of the cogongrass gall midge is a very limited. The objectives of this study was to describe and identify the new reported cogongrass gall midge parasitoids in Gunung Gadung cemetery in Cipaku, South Bogor District, Bogor. This study was conducted by taking the cogongrass galls in the field, maintaining in the laboratory, identificating the parasitoids, and calculating the percentage of parasitism. The study has been conducted from August 2020 to May 2021. Three new reported parasitoids were identified on O. javanica in addition to five already known parasitoid, they were Eurytoma sp. (Hymenoptera: Eurytomidae), Lamprotatus sp. (Hymenoptera: Pteromalidae), and Nigeriella sp. (Hymenoptera: Agaonidae). These parasitoids may be able to reduce the effectiveness of the cogongrass gall-midge in controlling the cogongrass. Their morphological characters, descriptions, and percentage of parasitism are presented.
Cucurbit aphid-borne yellows virus (CABYV) infecting melon and bitter gourd in Java, Indonesia
Authors: Damayanti T A , Rahmatilah M , Listihani  , Hidayat S H , Wiyono S
Published: December 2021

Recently, Cucurbit aphid-borne yellows polerovirus (CABYV) had been reported firstly to infect cucumber in Java. The typical symptoms of CABYV infection are leaf yellowing with green veins and the thickening of older leaves. This study aimed to detect and identify the occurrence of CABYV infection on other cucurbit hosts in Java. A total of 600 Polerovirus-like symptomatic leaves were taken from open-fields cultivated plants in West Java, Central Java, and East Java. The virus incidence was determined serologically, RT-PCR and DNA sequencing confirmed the identity of CABYV. Based on serological test revealed six virus species in single or multiple infections with varying incidence. Among tested plants, the CABYV DNA with size ± 489 bp was successfully amplified from melon in Kediri, Tulungagung, Nganjuk (East Java), Kulonprogo, and bitter gourd in Bogor. The sequencing result confirmed the identity of melon isolates from Nganjuk showed the highest similarity with the CABYV cucumber isolate from Nganjuk and Tulungagung. In contrast, bitter gourd isolates with melon isolates from France and squash isolates from Spain. These are the first reports of CABYV infection on melon and bitter gourd in Java, indicating its rapid host expansion on Cucurbitaceae.
Habitat use and diet of the bear cuscus Ailurops ursinus (Temminck, 1824) in various forest ecosystem types in South Sulawesi
Authors: Nugraha R , Andriyani A A , Marliana S N
Published: December 2021

The population of the bear cuscus Ailurops ursinus (Temminck, 1824), an arboreal marsupial endemic to Sulawesi, Indonesia, and its satellite islands, is declining rapidly due to poaching and habitat loss, even in protected areas. However, despite concerns over its persistence, little is actually known of this secretive species. This research investigated the characteristics of the selected habitats and diet of the bear cuscus in four ecosystem types (lowland non-dipterocarp forest, lowland limestone forest, lowland monsoon deciduous forest, lowland monsoon evergreen forest). Habitat use data were collected through direct encounters and indirect observations (tracks, signs, secondary information), and analyzed using a chi-square goodness-of-fit test. Habitat characteristics and diet availability were determined using vegetation analysis. Diet data were obtained using direct observations, feed remains, and interviews. The lowland non-dipterocarp forest ecosystem was used significantly more by bear cuscus populations. Its habitats across the four ecosystem types had similar environmental conditions. Fifty-five plant species, eaten mostly as young leaves and leaf buds, encompassed the bear cuscus’ diet, with the Moraceae family being the most representative. Considering the ubiquity of Moraceae in the bear cuscus’ habitat, these results highlight the impact unchecked deforestation will continue to have on lowland Indonesia and its endemic species.
Biology and life tables of Telenomus remus (Hymenoptera: Scelionidae) as parasitoid of Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae)
Authors: Oktaviani  , Maryana N , Pudjianto
Published: December 2021

Telenomus remus (Hymenoptera: Scelionidae), is an endoparasitoid on eggs of Spodoptera frugiperda (J. E. Smith). S. frugiperda. The information of T. remus as a natural enemy of S. frugiperda is very limited. The research objective is to determine some biological aspects of T. remus, i.e. longevity, fecundity, and life table variables. The demographic statistics using the jackknife method. T. remus is collected from the field identified as T. remus. The immature stage of T. remus reached 8.13 days, the longevity of the male was 10.07 days, while a female was 10.29 days with a fecundity of 75 eggs, and a sex ratio of male and female was 1:2.16. T. remus life table, i.e. gross reproduction rate (GRR) was 74.67 individuals/generation, net reproduction rate (R0) was 45260.60 females/females/generation, with generation period (T) was 8.62 days, and intrinsic rate of increase (r) was 1.24 females/female/day. The success parasitization of T. remus reaches 91%.
Flower-visiting insects to Coffea arabica flower at different temperatures and the production of the fruit of arabica coffee
Authors: Hafsah H , Iriawati I , Syamsudin T S
Published: December 2021

Temperature change may affect insect activity, including flower-visiting insects. Flower-visiting insects, particularly pollinators, have an impact on the fruits produced. This research aimed to study the relationships of flower-visiting insects at different temperatures and coffee production. The gauze experiment was carried out on the coffee plantation that consists of two sites, shaded and unshaded. The study involved 30 arabica inflorescences. The number of flower-visiting insects was recorded and captured. The results showed that the diversity of flower-visiting insects was related to the temperature differences. The flower-visiting insect on the unshaded site was more diverse than the shaded site. The formation of peaberries and the productivity of coffee fruit were also different. Peaberry production was lower (6.24 %) while the fruit mass was heavier (0.15±0.096 g/cherry) in unshaded than shaded sites. However, at the unshaded, the percentage of coffee beans defect was 0.56 % greater than the shaded one. According to these findings, more flower-visiting insects lead to the lower peaberry formation, the heavier fruit mass but potentially causing higher defective coffee beans. The increase in temperature due to climate change can be detrimental because these phenomena will increase the number of coffee fruit defects and insect pests.
Exploration of plant diversity at the forest patches in North Sulawesi and Their Conservation Strategy
Authors: Helmanto H , Siregar M , Rahmawati S U , Usman  , Sahrudin U
Published: December 2021

North Sulawesi is one of the provinces which is included in the Wallacea area which is the world’s source biological diversity and endemism hotspot. Forest fragmentation and population growth is the greatest threat to a variety of Wallacea endemic species. This study aims to explore the plant diversity in various forest patches in North Sulawesi and their conservation strategies. The research was conducted in 7 forest locations. This research uses exploration method. Exploration results found 259 collection numbers consisting of 154 species, 114 genera and 53 families. Orchidaceae is the most commonly family found (48 species and 26 genera), followed by Moraceae (18 species) and Piperaceae (16 species). Four species of Begonia were identified as endemic Sulawesi, 3 number potential as new species. Potential of new species is also likely on the Alpinia spp. (Zingiberaceae) and Piper spp. because has a large variety. Forest patches in the study area still have a high variety of species but mostly surrounded by people’s gardens and exploited potentially. In situ conservation complementary with ex situ is a conservation strategy which needs to be carried out.
Salinity stress affects growth and physiology of mulberry (Morus sp.)
Authors: Wulandari Y R E , Triadiati T , Sulistyaningsih Y C , Suprayogi A , Rahminiwati M
Published: December 2021

Mulberry (Morus sp.) plant is used to feed silkworms, and the leaves contain compounds with medicinal properties of secondary metabolites. However, the content of these compounds tends to increase under stress conditions, for instance, salt stress. This study, therefore, aimed to determine the accessions of mulberry with tolerance for salt stress. The stem cuttings of seven accessions from 5 regions, Bogor, Pati, Situbondo, Bali, and Gowa, were planted following a factorial randomized block design with 3 replications. Subsequently, the first factor using the accessions, and the second factor using NaCl solution (0.0%, 0.2%, 0.3%, and 0.4% concentrations) were performed. The variables observed were growth (leaves number, plant height, and shoots number), photosynthesis rate, total chlorophyll, and proline content. The results showed that the M6 accession exhibited tolerance under high salt stress, based on the leaves number, plant height, shoot number, photosynthesis rate, and proline content. Furthermore, an increase in salt concentration was discovered to cause a decrease in growth, photosynthesis rate, and total chlorophyll content. Also, proline accumulation stimulated by high salt stress possibly plays an important role in salinity tolerance.
Callus of Curculigo latifolia Dryand. ex W.T. Aiton: initiation, regeneration, secretory structure and histochemistry
Authors: Umar A H , Ratnadewi D , Rafi M , Sulistyaningsih Y C , Hamim H
Published: December 2021

In Indonesia, Curculigo latifolia, popularly known as lemba, is used as traditional medicine for antihypertension, antidiabetic, and as a food and drink additive. Despite the high benefits, this plant is difficult to propagate due to its low seed viability. Tissue culture offers an alternative for plant propagation, thus providing a continuous source of bioactive substances. The study aimed to establish efficient methods of explant sterilisation, callus induction and its regeneration from leaf tissues for plant multiplication. The study also investigated histochemically secondary metabolites produced by the callus. Our results showed that sterilising agents in the lowest concentrations and the shortest duration was the most suitable for getting aseptic cultures. BAP (3 mg L−1) and IBA (5 mg L−1) were the highest callus initiation, shoots, and roots regeneration. The histological sections of fresh callus showed secretory structure in the form of secretory cavities surrounded by a layer of epithelial cells and idioblasts around the secretory cavities. The histochemical tests identified phenolic compounds and essential oils in organogenic callus. Idioblasts were detected containing essential oils too. The results will contribute to C. latifolia propagation and the development of callus as a producing source of secondary metabolites.
The selection of laccase producing polypores fungi and inducer addition on the degradation of batik waste
Authors: Mantovany A F , Artika I M , Subowo YB
Published: December 2021

Research on the selection of laccase producing polypores fungi and inducer addition on the degradation of batik waste has been carried out. The objectives of this study were to obtain isolates of polypores fungi with high laccase activity and data on the inducer effect in the batik waste degradation by selected isolate. Batik waste is potential pollution to the environment. It has been found that the Polyporaceae fungus reduce water pollution caused by batik waste. Fungal fruiting bodies were collected at the Cibinong Science Center and forest park IPB Campus Darmaga, Bogor. The inducers used included 15 g/L sucrose, 200 μM CuSO4, and 1.5% sorghum waste. Seven isolates of polypores fungi were obtained. Isolate J6 with high laccase activity was obtained and identified as Coriolopsis sp. The addition of sorghum waste to the growth medium increased the laccase activity of Coriolopsis sp. J6 by 1428 U/mL. Coriolopsis sp. J6 was able to reduce the color of Poly R-478 by 83.73% after the addition of sucrose and incubation for 10 days. This fungus was able to reduce the color of batik waste by 37.17% after the addition of 1.5% sorghum waste and incubation for 10 days.
Uncovering the potential of actinobacterium BLH 1-22 isolated from marine sediment as a producer of antibiotics
Authors: Atikana A , Ratnakomala S , Nurzijah I , Sari M N , Agnestania A , Aisy II , Untari F , Fahrurozi F , Bintang M , Sukmarini L , Putra MY , Lisdiyanti P
Published: December 2021

Actinobacteria have been known as producers of many bioactive compounds. The present study examines ten marine Actinobacterial isolates, aiming to investigate their potential as producers of antimicrobial compounds. The secondary metabolites were extracted from these Actinobacteria using ethyl acetate, and the crude extracts were tested for their bioactivity againstEscherichia coli, Bacillus subtilis, andMicrococcus luteus. The antibacterial screening showed that the crude extracts of these Actinobacteria inhibit the growth of indicator strains. The extracts of isolate BLH 1-22 were further analysed using high-performance liquid chromatography (HPLC), which showed potential compounds with peak and retention time similar to the antibiotic standards (i.e., erythromycin, ampicillin, tetracycline, and penicillin). In addition to the HPLC profile, molecular identification showed that the isolate BLH 1-22 was similar toMicromonospora chalcea(99.6%). Further genome characterization of the strain, as well as purification and fractionation of the metabolite extracts, are important to obtain a comprehensive study on the potential of isolate BLH 1-22 as antibiotic compound producers. This study reported the potential ofMicromonosporaBLH 1-22 isolated from marine sediment. Hence, it also highlighted the potential of Actinobacteria isolated from Indonesian environments for bioprospecting studies.
Bioactive compounds derived from Streptomyces sp. SA32: antibacterial activity, chemical profile, and their related genes
Authors: Ryandini D , Radjasa O K , Oedjijono
Published: December 2021

Microbes which are resistant to drugs and antibiotics as well as multi-drug resistant (MDR) microbes have developed due to the improper use of antibiotics and led to explore the microbial isolates as the sources of new antibiotics or those with highly effective and stabile attack. Streptomyces sp. SA32 was selected to inhibit the growth of MDR bacteria Escherichia coli, Staphylococcus aureus, Klebsiella pneumonia, Pseudomonas aeruginosa, Enterobacter cloaceae, and Enterococcus sp. E. coli was sensitive to crude extracts of Streptomyces sp. SA32 at the concentration of 19 g.mL-1 with moderate strength against E. cloacae. The bioactive compounds analyzed using thin layer chromatography and phytochemical methods showed that the spot with Rf 0.63 and 0.68 was polyketide compound and that with Rf 0.74 was flavonoid compound. The bioautography assay on the TLC plate confirmed the absence of MDR bacterial growth on polyketide and flavonoid spots. The synthesis of antibacterial compounds was also confirmed by the successful analysis on both non-ribosomal peptide synthetase (NRPS) and polyketide synthase (PKS) gene sequences.