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51.
Purification and Chemical Analysis of Microbial Cell Flocculant Produced by Aspergillus sojae AJ7002
Junji Nakamura Shigeyoshi Miyashiro Yoshio Hirose 《Bioscience, biotechnology, and biochemistry》2013,77(3):619-624
A bio-flocculant was isolated from the culture broth of Asp. sojae AJ 7002. It was partially purified by acetone or ethanol precipitation, by ion-exchange and gel chromatography, and by dialysis. The isolated polymer possessed chemical characteristics of a poly-hexosamine and a protein. Glucosamine and galactosamine were not acetylated. The flocculant contained 2-ketogluconic acid, but sulfur or phosphorus was not detected. This flocculant was thermo-stable and its activity varied with pH. It was suggested that the hexosamine moiety in the polymer played a major role in bio-flocculation, assisted by protein portion in enlargement of the molecular weight of the flocculant, and by 2-ketogluconic acid in endowing it with amphoteric character. 相似文献
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Abstract A simple classical model is used for the study of the structural transformations of ice under high pressures, such as ice VIII to VII and X, via classical molecular dynamics (MD) simulation. In the present MD simulation, pair potentials of a simple form between pair of atoms and a thee-body potential representing the H-O-H angle dependence, originally developed by Kawamura et al., were used. Starting with a stable ice VIII at low pressure and low temperature, we have carried out two different MD runs, one with increasing pressure keeping the temperature constant (simulation I) and the other with increasing temperature under constant pressure (simulation II). From these MD simulations we have obtained the structural transformations from ice VIII to VII for both simulations; the former was finally transformed into ice X for the simulation I. The present results are compatible with recent experiments on high pressure ices. 相似文献
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Tadamichi Sonoda Hiroyuki Osada Junji Magae Kiyoshi Isono 《Bioscience, biotechnology, and biochemistry》2013,77(5):1259-1263
To investigate the immunosuppressive effects of glutarimide antibiotics including a new antibiotic named epiderstatin, we tested these antibiotics for inhibition of the blastogenesis of mouse spleen cells induced by mitogen stimulation (concanavalin A or lipopolysaccharide). The inhibitory activity was measured by colorimetric MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay. Among the glutarimide antibiotics tested, epiderstatin and acetoxycycloheximide especially strongly inhibited the blastogenesis of mouse spleen cells induced by concanavalin A and lipopolysaccharide, however, selectivity between T and B lymphocytes was not observed. 相似文献
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Dong Ki Park Junji Terao Setsuro Matsushita 《Bioscience, biotechnology, and biochemistry》2013,77(11):2443-2448
Trilinoleoylglycerol (TL) was autoxidized at 37°C in the dark. Monohydroperoxides (MHP) obtained from the oxidized products were analyzed by high performance liquid chromatography (HPLC). Several peaks which appeared in the chromatogram were identified by infrared (IR), gas chromatography mass spectrometry (GC-MS) and enzymatic hydrolysis. Some positional and geometrical isomers of their hydroperoxy fatty acid components were separated using both absorption and reversed phase systems. Furthermore, 1-hydroperoxylinoleoyl-2,3-dilinoleoyl-glycerol and 1,3-dilinoleoyl-2-hydroperoxylinoleoylglycerol were partly separated by HPLC using an absorption system. MHP obtained from autoxidized corn oil, safflower oil and soybean oil were separated into some peaks by HPLC, although resolution into the individual isomers was incomplete. When oxidized oils were subjected to HPLC analysis directly, a linear relationship was observed between the peak areas of MHP and peroxide value in the range of 10 ~ 50 meq/kg. 相似文献
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Junji Morita Naoki Kashimura Tohru Komano 《Bioscience, biotechnology, and biochemistry》2013,77(4):883-890
The inactivation of bacteriophage ?X174 by d-fructose 6-phosphate was investigated. This inactivation was inhibited by EDTA or reducing agents, and stimulated by Cu2+ but other metal ions could not be substituted for Cu2+. The reaction was also inhibited by superoxide dismutase (EC 1.15.1.1), catalase (EC 1.11.1.6) and various free radical scavengers.No detectable changes were observed in adsorption capacity of phage and in the conformation of the virion. The viral DNA in the virion was, however, found to be cleaved. This strand scission was also enhanced by Cu2+ and protected by catalase. Similar results were obtained when ?X174 DNA was directly treated with d-fructose 6-phosphate.It is concluded that the inactivation of ?X174 is due to DNA strand scission in the virion by the free radical of d-fructose 6-phosphate or oxygen radicals generated during autoxidation of d-fructose 6-phosphate. 相似文献
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Atushi Kato Hiroo Ueda Yohei Hashimoto 《Bioscience, biotechnology, and biochemistry》2013,77(1):28-31
(–)-Menthyl carbinol (1-(R)-methyl-3-(R)-hydroxymethyl-4-(S)-isopropylcyclohexane) (4) was prepared stereospecifically in good yield by treatment of formaldehyde with the Grignard reagent from (–)-menthyl chloride (2), which was prepared from (–)-menthol-(1-(R)-methyl-3-(R)-hydroxy-4-(S)-isopropylcyclohexane) (1) by chlorination using the Lucas reagent (HCl+ZnCl2). The configuration of 4 was assigned by the chemical method. 相似文献
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