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191.
Takuo Sakai Tatsurokuro Tochikura Koichi Ogata 《Bioscience, biotechnology, and biochemistry》2013,77(8):737-741
In this study, the authors developed a simplified method for the separation and the quantitative determination of nucleosides and bases, using paper electraophoretic technique. By this method, nucleosides and bases were well separated and determined in a fairly short time. Thus, this method was expected to be as accurate as the published methods and was believed to be a better method for both quantitative determination and detection of the nucleosides and bases in a large number of samples. 相似文献
192.
Sadao Sakamura Jiro Ito Ryutaro Sakai 《Bioscience, biotechnology, and biochemistry》2013,77(1):105-110
The additional new metabolites, named phyllostine (II) and 3-chloro-2,5-dihydroxybenzyl alcohol (III) from the cultural filtrates of Phyllosticta sp. have been isolated. The chemical structure of II have been established by spectral studies and chemical conversion from the known I, and the chlorine-containing metabolite (III) by spectral and synthetic studies. The metabolite (II) exhibits the similar phytotoxic effects as I, but the metabolite III does less phytotoxicity than I and II on the leaf test. 相似文献
193.
Naomichi Nishio Kenji Sakai Koji Fujii Tadashi Kamikubo 《Bioscience, biotechnology, and biochemistry》2013,77(3):553-559
The accumulation of vitamin B6 by Pichia guilliermondii Wickerham NK–2 strain grown on hydrocarbon was investigated. Ammonium acetate was more effective than other nitrogen sources tested. Satisfactory utilization by the yeast strain was observed in n-alkanes of C10–C18, and n-pentadecane was the best for vitamin B6 production. Vitamin B6 was excreted in the cultural broth mainly in the form of pyridoxal, The maximal vitamin B6 production was approximately 25 mg per liter of the culture broth. 相似文献
194.
Seiichi Nonomura Ryotaro Kotani Rintaro Urakabe Shoji Shima Heiichi Sakai 《Bioscience, biotechnology, and biochemistry》2013,77(9):1755-1756
A series of partially and heterogeneously N-acylated chitosans was prepared and isolated in 50 ~ 100% yields. The structure of N-acyl groups influenced the gelation. The minimum requirement for the gelation was defined as ca. 0.4 N-lauroyl (C12), ca. 0.6 N-fatty acyl (C3–C10) or ca. 0.7 N-benzoyl groups per hexosaminide residue. However, the gelation did not occur with N-high fatty acyl (C14-C18) groups.1) 相似文献
195.
Takayuki Aoyama Yasukazu Nakakita Masahira Nakagawa Heiichi Sakai 《Bioscience, biotechnology, and biochemistry》2013,77(9):2369-2371
Asymmetric hydrolysis of (dl)-1-acyloxy-2-halo-1-phenylethanes by lipoprotein lipase Amano P from Pseudomonas fluorescens and the lipase from Chromobacterium viscosum afforded the optically active (R) residual substrates and (S)-2-halo-1-hydroxy-1-phenylethanes in 100% enantiomeric excess (e.e.). The length of acyl residues from acetyl to octanoyl in the substrates did not influence the enantioselectivity.Both enantiomers of optically active styrene oxides were synthesized from the enzymatic products. 相似文献
196.
197.
Juichiro Yagi Tatsuo Yamashita Kazuo Kato Yoshimasa Takagi Heiichi Sakai Katsumi Shimizu 《Bioscience, biotechnology, and biochemistry》2013,77(3):340-352
Screening was carried out for erythorbic acid (EA)-producing strains from about 5,000 newly isolated fungi and bacteria. Penicillium notatum FY 115 was screened out as most powerful EA producer. Only Penicillium, but no other genera, was obtained as EA producers from our screening program. Monospore selections and mutagenic treatments succeeded to elevate the yield of EA over 40% to glucose supplied. Various cultural conditions were studied, and pH change during fermentation process was proved to be most important for favorable EA production. Over 80% yield could be obtained when washed mycelium was used in dilute glucose solution.Abundant accumulation of EA by the strain FY 115, Penicillium sp., in fermentation broth was studied, and EA, both free and Na-salt, was obtained as crystal in the yield of about 45% to glucose supplied, in the media of 8% glucose by jar fermentor, in considering the inhibitory effect of some metal ion.Extraction processes were improved to elevate the yield and was developed the continuous multi-bed extraction system of anion-exchange resin, which resulted in the yield of 90.9% of EA from fermentation broth in sum total. 相似文献
198.
Sadao Sakamura Hiroshi Niki Yataro Obata Ryutaro Sakai Takeshi Matsumoto 《Bioscience, biotechnology, and biochemistry》2013,77(5):698-703
In the course of phytopathological studies, it has been observed that phyllosticta sp. produces a toxic compound causing wilting and simultaneous dark coloration of the clover leaf. A toxin, herein refered to as phyllosinol (mp 76~77°C) was isolated in a crystalline state from the pure culture and it was proved to be the principal toxic metabolite of the fungus. Although the melting point of phyllosinol differed significantly from that reported for epoxydon (40~45°C), the structural evidence deduced from spectrometric and chemical methods indicates that phyllosinol is substantially identical with epoxydon even in stereo-isomeric considerations. In the red clover leaf test 10 ppm phyllosinol showed the wilting effect. 相似文献
199.
200.
Yusuke Sakai Makiko Koike Hideko Hasegawa Kosho Yamanouchi Akihiko Soyama Mitsuhisa Takatsuki Tamotsu Kuroki Kazuo Ohashi Teruo Okano Susumu Eguchi 《PloS one》2013,8(7)
Cell sheet engineering is attracting attention from investigators in various fields, from basic research scientists to clinicians focused on regenerative medicine. However, hepatocytes have a limited proliferation potential in vitro, and it generally takes a several days to form a sheet morphology and multi-layered sheets. We herein report our rapid and efficient technique for generating multi-layered human hepatic cell (HepaRG® cell) sheets using pre-cultured fibroblast monolayers derived from human skin (TIG-118 cells) as a feeder layer on a temperature-responsive culture dish. Multi-layered TIG-118/HepaRG cell sheets with a thick morphology were harvested on day 4 of culturing HepaRG cells by forceful contraction of the TIG-118 cells, and the resulting sheet could be easily handled. In addition, the human albumin and alpha 1-antitrypsin synthesis activities of TIG-118/HepaRG cells were approximately 1.2 and 1.3 times higher than those of HepaRG cells, respectively. Therefore, this technique is considered to be a promising modality for rapidly fabricating multi-layered human hepatocyte sheets from cells with limited proliferation potential, and the engineered cell sheet could be used for cell transplantation with highly specific functions. 相似文献