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101.
In the course of investigation of alicyclic hydrocarbon-utilizing microorganisms, five strains of ethylcyclohexane-utilizing bacteria were isolated from soil samples.Among those bacteria, the strain S6B1 that was identified as Alcaligenes faecalis, showed the best growth in shaking culture.The strain S6B1 was found to produce 4-ethylcyclohexanol from ethylcyclohexane.This substance separated from culture broth was purified and identified to be trans-4-ethylcyclohexanol by the use of NMR. 相似文献
102.
Yoshikazu Izumi Kuninori Sato Yoshiki Tani Koichi Ogata 《Bioscience, biotechnology, and biochemistry》2013,77(11):2683-2684
Vitamin B6 is synthesized by green Cytisus scoparius callus and green Phellodendron amurense callus cultured on Linsmaier and Skoog Agar-medium with 10?5m of ±-naphthaleneacetic acid (NAA) and 10?6 m of 6-benzyladenine (BA). Even when thiamine and inositol were omitted from this medium, the growth and vitamin B6 content of Cytisus scoparius callus did not change. Vitamin B6 contents of clones of the calluses varied and were unstable during long-term subculture. Clonal selection was repeated to obtain stable strains with high vitamin B6 content, and the vitamin B6 content of one strain of green Cytisus scoparius callus became 4-times higher than that of the green leaves. 相似文献
103.
Shuuji Yamamoto Yasuji Minoda Koichi Yamada 《Bioscience, biotechnology, and biochemistry》2013,77(12):2097-2103
Some chemical and physicochemical properties of the purified phytase preparation produced by Asp. terreus were investigated. From the results of the examination of amino acid analysis, it was suggested that there existed some components other than amino acids in the purified enzyme. Examination of the neutral sugar analysis, therefore, was made by gaschromatography, and it was found that the purified enzyme preparation contained mannose, galactose and a small amount of inositol.The molecular weight of the enzyme was found to be 214,000 by the Archibald method, and 2.2~2.3×105 by gel-filtration on a Sephadex G–200 column. It was found that by guanidine hydrochloride or by urea, the purified enzyme preparation was dissociated into only one kind of subunit. The native enzyme was supposed to be a homohexamer of the subunits whose molecular weight is 37,000. 相似文献
104.
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
105.
Takashi Matsumoto Daisuke Yoshida Shigenobu Mizusaki Hideo Tomita Koichi Koshimizu 《Bioscience, biotechnology, and biochemistry》2013,77(4):861-864
The mutagenic activities of quinoline, isoquinoline, phenanthridine, benzo(f)quinoline, benzo(h)quinoline and their α-amino derivatives were compared in relation to the effect of structural changes using the Salmonella typhimurium test system. All mutagenic compounds tested require the liver microsomal fraction for their mutagenic activity. Phenanthridine, two benzoquinolines and quinoline were mutagenic. α-Amination of two benzoquinolines and quinoline resulted to increase their mutagenic activity intensively. Addition of a benzene ring to the benzene moiety of 2-aminoquinoline, so that two carbon atoms are shared, affected distinctly the increase in the mutagenic activity. The co-existence of benzoquinoline series with 2-aminobenzo(f)quinoline showed the clear synergistic action. 相似文献
106.
107.
Hiroshi Fukui Hiroshi Egawa Koichi Koshimizu Tetsuo Mitsui 《Bioscience, biotechnology, and biochemistry》2013,77(2):417-421
A new isoflavone having antifungal activity was isolated from immature fruits of Lupinus luteus (Leguminosae), and named luteone. The structure was shown to be 5,7,2′,4′-tetrahy-droxy-6-(3,3-dimethylallyl)-isoflavone by degradative and spectroscopic studies. 相似文献
108.
Kichitaro Kawaguchi Koichi Ogata Tatsurokuro Tochikura 《Bioscience, biotechnology, and biochemistry》2013,77(6):908-918
Effects of various factors including incubation time, water content of airdried cells, concentration and pH of KH2PO4–K2HPO4 mixture, d-glucose concentration, MgSO4 concentration, GMP concentration, cell concentration, aeration and various kinds of carbohydrates on the fermentative production of GDP-mannose, GDP and GTP from 5′-GMP by air-dried cells of baker’s yeast were investigated. The water content of air-dried cells was the most important factor in the fermentation. When the air-dried cells of baker’s yeast (100 mg/ml) were incubated with 5′-GMP (20 μmoles/ml), d-glucose (800 μmoles/ml), potassium phosphate buffer (360 μmoles/ml, pH 7.0), and MgSO4 (20 μmoles/ml), 2-hr incubation gave GDP in 20% yield and GTP in 61.1% yield, GDP-mannose being produced in 45% yield after 8-hr incubation. The phosphorylation of 5′-AMP, 5′-dAMP, 5′-dGMP 5′-CMP and 5′-UMP was also observed in high yields under the same conditions. 相似文献
109.
Fusako Kawai Kensei Maezato Hideaki Yamada Koichi Ogata 《Bioscience, biotechnology, and biochemistry》2013,77(9):1675-1679
The formation of D-pantothenic acid-α-glucoside (PaA-α-G) was found from D-pantothenic acid (PaA) and maltose in incubation mixtures of microorganisms, especially Saccharomyces yeasts and Sporobolomyces coralliformis IFO 1032. The reaction conditions were investigated for formation of PaA-α-G by resting cells of Spor. coralliformis. The formation of the compound increased with PaA concentration (3~20 mg/ml). The yield was maximum at 5~10 mg/ml of PaA. Cetyl trimethyl ammonium bromide (0.1 %) promoted the formation of PaA-α-G. Sucrose was the optimal α-glucosyl donor. When 30 mg/ml of sucrose was fed to the reaction mixture (initial sucrose, 100 mg/ml; and PaA, 10 mg/ml) at 12-hr intervals, 5.74 mg/ml (3.30 mg/ml as PaA) of PaA-α-G was formed in 48-hr incubation at 28°C with shaking. PaA-α-G was also formed by yeast α-glucosidase, mold maltase and the cell-free extract of Spor. coralliformis. The compound showed approximately 9~10% and 0.1~0.3% (molar ratio) of activity of PaA for Saccharomyces carlsbergensis ATCC 9080 and Lactobacillus plantarum ATCC 8014, respectively. The compound had the same microbiological activity as authentic 4′-O-(α-D-glucopyranosyl)-D-pantothenic acid. 相似文献
110.
Kenji Aoki Motoo Arai Yasuji Minoda Koichi Yamada 《Bioscience, biotechnology, and biochemistry》2013,77(12):1913-1920
The Acid-stable α-amylase and the acid-unstable α-amylase from Aspergillus niger contained one mole of sulfhydryl group per one mole of enzyme, which probably existed correlating with calcium atom that was essential for the amylase activity.Iodine reacted at acidic pH specifically with the sulfhydryl group of both enzymes and oxidized it to considerably high degree, since about 4 eq of iodine per mole of sulfhydryl group of both enzymes were consumed. The modification of the sulfhydryl group of the acid-stable α-amylase did not affect the amylase acitvity, while, that of the acid-unstable α-amylase reduced it to 70 per cents intact enzyme. It was difficult to carry out carboxy-methylation of the sulfhydryl group of the acid-stable α-amylase under mild conditions maintaining its activity, but that of the acid-unstable α-amylase was easily achieved.These facts suggested that some differences existed in the neighborhood of the sulfhydryl group of both enzymes, and that the sulfhydryl group of them was not the active site. 相似文献