bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of fungicidal activity of extracellular filtrates of cyanobacteria – possible role of hydrolytic enzymes
Authors: Prasanna Radha , Nain Lata , Tripathi Ravindramani , Gupta Vishal , Chaudhary Vidhi , Middha Sheetal , Joshi Monica , Ancha Radhika , Kaushik Brahma D. 
Published: May 2008

AbstractA set of seventy axenised and unicyanobacterial isolates belonging to the genus Anabaena were evaluated for biocidal activity against a set of phytopathogenic fungi. Among them, 35 Anabaena strains showed zone of inhibition against one or more fungi. The extracellular filtrates from 4 and 8 weeks old cultures of these Anabaena strains were further evaluated in terms of hydrolytic enzymes, proteins and IAA employing standard methods. Significant differences were also observed among the strains in terms of their FPase, chitosanase and xylanase activity, while low and relatively similar values of CMCase, cellobiase and protease activity were recorded in the strains analyzed. IAA production was also observed in all the strains. Comparative evaluation of activity of hydrolytic enzymes and antifungal activity revealed that such enzymes may contribute to the fungicidal activity of the cyanobacterial strains, besides other bioactive compounds, including IAA, which are established promising traits for biocontrol agents. This study is a first time report on the production of hydrolytic enzymes by these oxygenic photosynthetic prokaryotes, which can be potential candidates for the development of biocontrol agent(s) against selected phytopathogenic fungi. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Isolation, characterization of heavy metal resistant strain of Pseudomonas aeruginosa isolated from polluted sites in Assiut city, Egypt
Authors: Hassan S. H. A. , Abskharon R. N. N. , Gad El‐Rab S. M. F. , Shoreit A. A. M. 
Published: May 2008

AbstractSixty six isolates of Pseudomonas spp. were isolated from wastewater of El‐Malah canal located in Assiut, Egypt and were checked for their heavy metal tolerance. One isolate has tested for its multiple metal resistances and found to be plasmid mediated with molecular weight 27 Kb for nickel and lead. It was identified as Pseudomonas aeruginosa ASU 6a. Its minimal inhibitory concentration (MIC) for Cu2+, Co2+, Ni2+, Zn2+, Cr3+, Cd2+and Pb2+ were 6.3, 5.9, 6.8, 9.2, 5.8, 4.4, and 3.1 mM, respectively. Growth kinetics and the maximum adsorption capacities were determined under Ni2+ and Pb2+ stress. The latter heavy metals induced potassium efflux and were used as indicator for plasma membrane permeabilization. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Production of an extracellular thermohalophilic lipase from a moderately halophilic bacterium, Salinivibrio sp. strain SA‐2
Authors: Amoozegar Mohammad Ali , Salehghamari Ensieh , Khajeh Khosro , Kabiri Mahbube , Naddaf Saied 
Published: May 2008

AbstractFifty strains of moderately halophilic bacteria were isolated from various salty environments in Iran. A strain designated as SA‐2 was shown to be the best producer of extracellular lipase and was selected for further studies. Biochemical and physiological characterization along with 16S rDNA sequence analysis placed SA‐2 in the genus Salinivibrio. The optimum salt, pH, temperature and aeration for enzyme production were 0.1 M KCl, pH 8, 35 °C and 150 rpm, respectively. The enzyme production was synchronized bacterial growth and reached a maximum level during the early‐stationary phase in the basal medium containing 1 M NaCl. Triacylglycerols enhanced lipase production, while carbohydrates had inhibitory effects on it. The maximum lipase activity was obtained at pH 7.5, 50 °C and CaCl2 concentration of 0.01 M. The enzyme was stable at pH range of 7.5–8 and retained 90% of its activity at 80 °C for 30 min. Different concentrations of NaNO3, Na2SO4, KCl and NaCl had no affect on lipase stability for 3 h. These results suggest that the lipase secreted by Salinivibrio sp. strain SA‐2 is industrially important from the perspective of its tolerance to a broad temperature range, its moderate thermoactiviy and its high tolerance to a wide range of salt concentrations (0–3 M NaCl). (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Prehistoric rock crystal artefacts from Lower Silesia (Poland)
Authors: Sachanbiński M. , Girulski R. , Bobak D. , Łydżba‐Kopczyńska B. 
Published: May 2008

AbstractThe analysis of inclusions utilising optical methods and micro‐Raman spectroscopy was used to address a question of provenance of prehistoric rock‐crystal artefacts excavated in Lower Silesia (SW Poland). The nature and spectroscopic features of inclusions in rock crystal from three Lower Silesian deposits were established and compared with the ones identified in the rock‐crystal artefacts. A characteristic inclusion assemblage in rock crystal from the Jegłowa–Krzywina deposit consists of anatase, kaolinite, and chlorite. Quartz from granitic pegmatites of the Jelenia Góra Valley displays the presence of dusty hematite coating. Frequent inclusions of goethite are typical of rock crystal from cavities in volcanic rocks near Kłodzko. The study established that raw material used to manufacture 16 of the artefacts investigated comes from the Jegłowa–Krzywina quartz deposit. One tool was made of the material obtained from granitic pegmatites that occur near Karpniki (Jelenia Góra Valley). Two other artefacts contain inclusions not found in crystals from any of the investigated Lower Silesian deposits. Copyright © 2008 John Wiley & Sons, Ltd.
Anti‐influenza virus activity of extract of Japanese wasabi leaves discarded in summer
Authors: Mochida Kyo , Ogawa Tetsuro 
Published: May 2008

AbstractBACKGROUND: Japanese wasabi (Wasabia japonica) is now habitually used as a spice in some kinds of Japanese foods, and its pungent taste and flavor are preferred. Generally, rhizomes and winter leaves are used as a spice and for processed foods such as pickled wasabi. Since the leaf area of summer leaves is far greater than that of winter leaves, they are not used for food, and are discarded. Thus, we need to develop an effective use for summer leaves. We investigated anti‐influenza virus activity in these summer leaves as a new function.RESULTS: Seventy percent ethanol extracts of leaves harvested in July exhibited a high replication inhibition rate (98% or higher) in the type A strain (AH1N1, A/shimane/48/2002), its subtype (AH3N2, A/shimane/122/2002), and type B strain (B/shimane/2/2002). The extracts of summer leaves exhibited the same anti‐influenza virus activity as winter leaves, and showed a stronger activity than stems, roots, and rhizomes.CONCLUSION: A potent anti‐influenza virus activity was discovered in summer leaves of Japanese wasabi. The ethanol extracts inhibited influenza virus replication regardless of the hemagglutinin antigen type. Therefore, such extracts are expected to be a promising source of a novel anti‐influenza virus agent. Copyright © 2008 Society of Chemical Industry
Effects of amounts of HMW glutenin subunits determined by capillary electrophoresis on technological properties in wheat doubled haploids
Authors: Salmanowicz Bolesław P , Surma Maria , Adamski Tadeusz , Rębarz Michał 
Published: May 2008

AbstractBACKGROUND: Knowledge of the types and amounts of individual HMW glutenin subunits (HMW‐GS) is important for predicting technological quality. In this study, 228 wheat doubled haploids were compared in respect of HMW‐GS composition, seed protein content, flour yield, rheological properties of dough, and loaf properties. The quantitative and qualitative composition of particular HMW‐GS was determined by CE. The relative amounts of x‐type and y‐type subunits encoded by individual Glu‐1 loci were considered.RESULTS: The results show that the amounts of some pairs x + y of HMW‐GS are correlated with technological properties. The importance of quantities of particular pairs of HMW‐GS for technological values depends on allele compositions in all the Glu‐1 loci. Positive correlation was found between the amount of subunits Ax1, Ax2*, Bx7 + By8 or Dx5 + Dy10 and loaf volume (r = 0.215–0.618, P < 0.05). The influence of an increasing amount of Ax1 was positively correlated with dough softening (r = 0.451, P < 0.01) and negatively with dough development time (r = − 0.209, P < 0.05) and stability (r = − 0.351, P < 0.01), whereas for subunit Ax2* these associations were opposite.CONCLUSION: The results confirm the occurrence of epistatic interactions between alleles of Glu‐1 loci. The effects of amounts of HMW subunits on bread‐making quality should be considered only within glutenin subunit compositions. Copyright © 2008 Society of Chemical Industry
Photopolymerized Injectable RGD‐Modified Fumarated Poly(ethylene glycol) Diglycidyl Ether Hydrogels for Cell Growth
Authors: Akdemir Z. Seden , Akçakaya Handan , Kahraman M. Vezir , Ceyhan Taşkın , Kayaman‐Apohan Nilhan , Güngör Atilla 
Published: May 2008

AbstractIn this study, photopolymerized hydrogels of fumarated poly(ethylene glycol) diglycidyl‐co‐ poly(ethylene glycol) diacrylate have been synthesized and modified with cell adhesion peptide, Arg‐Gly‐Asp (RGD). The structural and mechanical properties of the hydrogels are found to be poly(ethylene glycol) diacrylate (PEGDA) dependent. The percentage of gelation is increased from 72 to 89 wt.‐% when the amount of the crosslinker co‐monomer (PEGDA) in the hydrogel formulation is increased from 20 to 40 wt.‐%. In the present case, the equilibrium mass swelling is decreased from 216 to 93%. The viscosities of the uncured formulations have also been measured and likewise, the results were influenced by the increasing amount of PEGDA that reduced the value from 83 to 36 cP. The compressive modulus of the prepared hydrogels was improved with the addition of the PEGDA. Cell growth experiments have been performed by comparing the properties of the hydrogels with and without RGD units. The results show that RGD units enhance the adhesion of cells to the surface of the hydrogels. SEM‐EDS studies reveal that nitrogen and calcium are produced on the osteoblast‐seeded surface of the scaffold within the culture time period.magnified image
Synthesis of Fluorescent Polyisoprene Nanoparticles and their Uptake into Various Cells
Authors: Lorenz Myriam R. , Kohnle Maria‐Verena , Dass Martin , Walther Paul , Höcherl Anita , Ziener Ulrich , Landfester Katharina , Mailänder Volker 
Published: May 2008

AbstractFluorescent polyisoprene nanoparticles were synthesized by the miniemulsion technique as marker particles for cells. The uptake of the non‐functionalized polyisoprene nanoparticles, without any transfection agents, into different adherent (HeLa) and also suspension (Jurkat) cell lines is strikingly efficient and fast compared to other polymeric particles, and leads to high loading of the cells. The intracellular polyisoprene particles are localized as single particles in endosomes distributed throughout the entire cytoplasm. The uptake kinetics shows that particle internalization starts during the first minutes of incubation and is finished after 48 h of incubation. Since (unfunctionalized) polystyrene particles show a comparable, low uptake behavior in cells, the uptake rates can be tuned by the amount of polystyrene in polyisoprene/polystyrene copolymer particles. As polyisoprene nanoparticles are internalized by different cell lines that are relevant for biomedical applications, they can be used to label these cells efficiently if a marker is incorporated in the particles. As polyisoprene is not or is hardly biodegradable the particles should be suited for long‐term applications.magnified image
Fibrinolytic Poly(dimethyl siloxane) Surfaces
Authors: Chen Hong , Wang Liang , Zhang Yanxia , Li Dan , McClung W. Glenn , Brook Michael A. , Sheardown Heather , Brash John L. 
Published: May 2008

AbstractPDMS surfaces have been modified to confer both resistance to non‐specific protein adsorption and clot lyzing properties. The properties and chemical compositions of the surfaces have been investigated using water contact angle measurements, ATR FT‐IR spectroscopy, and XPS. The ability of the PEG component to suppress non‐specific protein adsorption was assessed by measurement of radiolabeled fibrinogen uptake from buffer. The adsorption of plasminogen from human plasma to the various surfaces was studied. In vitro experiments demonstrated that lysine‐immobilized surfaces with free ε‐amino groups were able to dissolve fibrin clots, following exposure to plasma and tissue plasminogen activator.magnified image
Poly(glycerol sebacate) Nanofiber Scaffolds by Core/Shell Electrospinning
Authors: Yi Feng , LaVan David A. 
Published: May 2008

AbstractThe novel biomaterial poly(glycerol sebacate) (PGS) holds great promise for tissue engineering and regenerative medicine. PGS is a rubbery, degradable polymer much like elastin; however, it has been limited to cast structures. This work reports on the formation of PGS nanofibers in random non‐woven mats for use as tissue engineering scaffolds by coaxial core/shell electrospinning. PGS nanofibers are an inexpensive and synthetic material that mimics the chemical and mechanical environment provided by elastin fibers. Poly(lactide) was used as the shell material to constrain the PGS during the curing process and was removed before cell seeding. Human microvascular endothelial cells from skin (HDMEC) were used to evaluate the in‐vitro cellular compatibility of the PGS nanofiber scaffolds.magnified image
Modification of Polymer Surfaces by Click Chemistry
Authors: Fleischmann Sven , Hinrichs Karsten , Oertel Ulrich , Reichelt Senta , Eichhorn Klaus‐Jochen , Voit Brigitte 
Published: May 2008

AbstractSilicon substrates were coated with well‐defined glycidyl and alkyne groups containing terpolymer that was synthesized by NMRP. The polymer was successfully tethered on silicon wafers and the resulting solvent stable, homogeneous, smooth thin films were characterized by means of atomic force microscopy (AFM), spectroscopic ellipsometry in the visible (Vis), and infrared (IR) spectral range. Subsequently, the films were modified in a heterogeneous reaction, converting the alkyne groups of the surface efficiently and quantitatively with azides by click chemistry. Appropriate film analysis allowed to directly verify the reaction of the alkyne groups with the azides and revealed that the chemical and physical properties of the thin films have changed while their morphology and topography is preserved.magnified image
Broadband Dielectric Relaxation Spectroscopy in Polymer Nanocomposites
Authors: Pissis Polycarpos , Fragiadakis Daniel , Kanapitsas Athanasios , Delides Kostas 
Published: May 2008

AbstractSummary: Dielectric spectroscopy in the frequency domain and thermally stimulated depolarization currents techniques, covering together a broad frequency range (10−4–109 Hz), were employed to investigate molecular dynamics in relation to structure and morphology in polymeric nanocomposites. Several systems were investigated, three of them with the same epoxy resin matrix and different inclusions (modified smectite clay, conducting carbon nanoparticles and diamond nanoparticles) and two with silica nanofiller (styrene‐butadiene rubber/silica and polyimide/silica nanocomposites). Special attention was paid to the investigation of segmental dynamics associated with the glass transition of the polymer matrix, in combination also with differential scanning calorimetry measurements. Effects of nanoparticles on local (secondary) relaxations and on the overall dielectric behavior were, however, also investigated. Several interesting results were obtained and discussed for each of the particular systems. Two opposite effects seem to be common to the nanocomposites studied and dominate their behavior: (1) immobilization/reduction of mobility of a fraction of the chains at the interface to the inorganic nanoparticles, due to chemical or physical bonds with the particles, and (2) loosened molecular packing of the chains, due to tethering and geometrical confinement, resulting in an increase of free volume and of molecular mobility.
Temperature Effect on Drying and Swelling of Kappa Carrageenan Gels: A Steady State Fluorescence Study
Authors: Tarı Ozlem , Pekcan Onder 
Published: May 2008

AbstractSummary: A novel technique based on in situ steady state fluorescence (SSF) measurements is introduced for studying drying and swelling of κ‐ carrageenan (kappa carrageenan) gels at various temperatures. κ‐ carrageenan gels were completely dried and then swelled in water vapor. Pyranine was embedded in κ‐ carrageenan and used as a fluorescence probe. Scattered light intensities, Isc and fluorescence intensities, I were monitored during the drying and swelling of κ‐ carrageenan gels. It was observed that the fluorescence intensity decreased linearly as drying time was increased. A simple model consisting of Case II diffusion was used to quantify the drying processes of the κ‐ carrageenan gels. This moving boundary model provided packing constant, k0. During swelling, fluorescence intensity increased exponentially as time is increased. The increase in I, was modeled using Li‐Tanaka equation from which swelling time constants, τc and cooperative diffusion coefficients, Dc were determined. It was observed that swelling time constants, τc decreased and diffusion coefficients, Dc increased as the swelling temperature was increased. Activation energies for drying and swelling were also obtained and found to be 53.9 and 47.2 kJ mol−1, respectively.
Vibrational Dynamics of Polyaniline Pernigraniline Base Form: A Conducting Polymer
Authors: Mishra Abhishek Kumar , Tandon Poonam , Gupta V. D. 
Published: May 2008

AbstractSummary: Polyaniline is unique among conducting polymers in that its electrical properties can be reversibly controlled both by the oxidation state of the main chain and by protonation. In the present communication we report normal modes and their dispersion in polyaniline pernigraniline base (PANI PNB) form using Urey ‐ Bradely force field which in addition to valence force field accounts for the non‐bonded interactions in the gem and cis configurations and tension terms. Some of the distinguished features of the dispersion curves such as cross‐over and Von Hove type of singularities are discussed and possible explanations are given in terms of symmetry considerations. Several new assignments, which are missing in earlier work, are reported.
ESR ‐ Spin Probe Method in Studying Natural Rubber: an Effect of the Probe Incorporation Temperature
Authors: Didović Mirna , Klepac Damir , Valić Srećko 
Published: May 2008

AbstractSummary: Natural rubber (NR) latex containing 62 wt.% of solid phase was dried by evaporating the liquid phase at room temperature. 4‐hydroxy‐2,2,6,6‐tetramethyl‐ piperidine‐1‐oxyl free radical, used as the spin probe, was incorporated into the NR matrix by swelling the samples in toluene probe solution at 4 °C, 24 °C and 37 °C. The probe incorporation temperatures were constant for each set of samples. When the solvent was slowly removed, all samples were annealed at 60 °C during 72 hours. Composite ESR spectra observed in the vicinity of T5mT show a significant influence of the probe incorporation temperature on the spectral shape. More precisely, the amount of the broad component in a composite ESR spectrum increases with the increasing probe incorporation temperature. A simple model which describes the probe distribution inside the inhomogeneous NR matrix is proposed.
Micro Raman Spectroscopy of Silica Nanoparticles Treated with Aminopropylsilanetriol
Authors: Volovšek V. , Furić K. , Bistričić L. , Leskovac M. 
Published: May 2008

AbstractSummary: Micro Raman spectroscopy was used to investigate the structures formed at the surface of amorphous pirogenic silica Aerosil 200. Nanoparticles were treated with 25% water solution of aminopropylsilanetriol and dried in laboratory atmosphere and under vacuum of about 5 mbar. Spectra of pure silica nanoparticles and treated nanoparticles were recorded in the frequency range 20–1700 cm−1 and 2500–3800 cm−1. Comparative analysis reveals the existance of different structures formed at the surface of silica nanoparticles depending on drying conditions.
Thermal Degradation of Poly(ε‐caprolactone), Poly(L‐lactic acid) and their Blends with Poly(3‐hydroxy‐butyrate) Studied by TGA/FT‐IR Spectroscopy
Authors: Vogel Christian , Siesler Heinz W. 
Published: May 2008

AbstractSummary: The thermal degradation behavior of poly(ε‐caprolactone) (PCL) and poly(L‐lactic acid) (PLA) have been studied in different environment. It was found that these polymers undergo completely different degradation processes in nitrogen and oxygen atmosphere. In oxygen environment PCL and PLA mainly decompose to CO2, CO, water and short‐chain acids. In nitrogen atmosphere PCL releases 5‐hexenioc acid, CO2, CO and ε‐caprolactone, whereas PLA decomposes to acetaldehyde, CO2, CO and lactide. The polymer blends of poly(3‐hydroxybutyrate) (PHB) with PCL and PLA decompose similar to the individual homopolymers with crotonic acid as the initial decomposition product of PHB.
In situ ATR‐FTIR Spectroscopy of Poly(ethylene terephthalate) Subjected to High‐Temperature Methanol
Authors: Andanson Jean‐Michel , Kazarian Sergei G. 
Published: May 2008

AbstractSummary: In situ ATR‐FTIR (attenuated total reflection Fourier transform infrared) spectroscopy combined with a high‐pressure cell has been applied to measure IR spectra of polymers subjected to superheated or near‐critical methanol (100– 200 °C). Spectra of poly(ethylene terephthalate) (PET) have been measured under exposure to high temperature methanol using this ATR‐FTIR approach to understand at a molecular level the recycling process of PET. The evolution of the structure and the morphology of the polymer has been studied during the methanolysis. The quantity of trans PET conformer is generally used as a tracer of the crystallinity of PET. During depolymerisation of PET the evolution of crystallinity and of trans conformer appears to be different. The dependence of the rate constant on reaction temperature was correlated by Arrhenius plot, which shows activation energy of 5.8 kJ/mol.
Infrared Intensity Studies in Fluorinated Macromolecules
Authors: Radice S. , Canil G. , Toniolo P. , Guarda P.A. , Petricci S. , Milani A. , Tommasini M. , Castiglioni C. , Zerbi G. 
Published: May 2008

AbstractSummary: Functionalized perfluoropolyethers are investigated by infrared spectroscopy with the aim to give a quantitative estimate of the carboxylic acid groups species; since hydrogen bonded moieties have been observed, also the relative distribution of the associated species has been determined. The study is based both on measured and on theoretically predicted infrared intensities, as obtained by density functional theory (DFT) calculations on model systems.