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111.
A polyuronide, main component of the water extract of achine of Ficus awkeotsang MAKINO (on-gyo-tye), was purified by ion-exchange chromatography on DEAE-cellulose. The polyuronide (Fraction IB) is homogeneous electrophoretically and consists mainly of galacturonic acid. Optical rotation of Fraction IB is and content of methoxyl group is trace. In periodate oxidation of Fraction IB, molar ratio of galacturonic acid residue and periodate consumption was 1, and formic acid formation was very small. Periodate oxidation product of Fraction IB was oxidized further with bromine and the resulted substance was hydrolyzed. In the hydrolyzate, presence of large amount of tartaric and glyoxylic acids and small amount of tartronic acid were detected by paper chromatography. Reduced viscosity of aquous solution of Fraction IB increased with decreasing of the concentration of Fraction IB solution. From these results, it was deduced that Fraction IB has a linear structure of 1→4 linkage of d-galacturonic acid, probably α-linkage. 相似文献
112.
Yoshimitsu Ueno Takao Ikami Ryo Yamauchi Koji Kato 《Bioscience, biotechnology, and biochemistry》2013,77(11):2623-2629
An α-galactosidase from tubers of S. affinis was purified about 130 fold by ammonium sulfate fractionation, chromatography on DEAE-cellulose and gel filtration on Sephadex G-75. The purified enzyme showed a single protein band on disc gel electrophoresis. The molecular weight of the enzyme was determined to be approximately 42,000 by gel filtration and 44,000 by SDS disc gel electrophoresis. The optimum reaction pH was 5.2. The enzyme hydrolyzed raffinose more rapidly than planteose. The activation energy of raffinose and planteose by the enzyme was estimated to be 7.89 and 11.4 kcal/mol, respectively. The enzyme activity was inhibited by various galactosides and structural analogs of d-galactose. Besides hydrolytic activity, the enzyme also catalyzed the transfer reaction of d-galactosyl residue from raffinose to methanol. 相似文献
113.
Minora Nakajima Junichi Oda Hiroshi Fukami 《Bioscience, biotechnology, and biochemistry》2013,77(10):695-699
Nodakenetin and marmesin were synthesized from β-resorcylaldehyde through 2-(α-hy-droxyisopropyl)-6-hydroxycoumaran. 相似文献
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115.
Takao Terashita Kōhei Oda Matashi Kōno Sawao Murao 《Bioscience, biotechnology, and biochemistry》2013,77(9):1937-1943
A Streptomyces-pepsin inhibitor (S-PI or Pepstatin Ac), and DAN-insensitive carboxyl proteinase was found in a still culture filtrate of Lentinus edodes. The new carboxyl proteinase was purified, and about 9 mg purified enzyme was obtained from 19 liters of culture filtrate, with 11% recovery. The enzyme showed a single band on polyacrylamide gel electrophoresis. The molecular weight and isoelectric point were 40,000 and pH 4.2, respectively. The enzyme did not contain histidine and was composed of 387 amino acid residues. The enzyme was most active between pH 2.7 ~ 2.9, and stable over a pH of 3.2 ~ 5.2 for 3 hr at 37°C. The enzyme was not inhibited by S-PI or synthetic pepsin inhibitors such as DAN and EPNP. The physicochemical and enzymological properties were very similar to those of Scytalidium lignicolum carboxyl proteinase A, which was reported to be an S-PI-, and DAN-insensitive carboxyl proteinase. 相似文献
116.
Hiroshi Fukui Ryoichi Nemori Koichi Koshimizu Yoshimitsu Yamazaki 《Bioscience, biotechnology, and biochemistry》2013,77(1):181-187
The structures of three new gibberellins A30, A48 and A49 and a new kaurenolide, isolated from seeds of Cucurbita pepo L., were elucidated. The structures of GA39, GA48 and GA49 were shown to be ent-3α,12β-dihydroxygibberell-16-ene-7,19,20-trioic acid (1), ent-2α,3α,10,12α-tetrahydroxy-20-norgibberell-16-ene-7,19-dioic acid 19,10-lactone (5) and the epimer at C–12 of GA48 (8), respectively. The kaurenolide was shown to have the structure: ent-6β,7α,12β-trihydroxykaur-16-en-19-oic acid 19,6-lactone (14). 相似文献
117.
Kohei Oda Takanori Imanishi Yoshito Yamane Yoshie Ueno Yoshiharu Mori 《Bioscience, biotechnology, and biochemistry》2013,77(5):882-890
Addition of γ-aminobutyric acid (GABA) and angiotensin converting enzyme (ACE)-inhibitory peptides to the pickles was studied in order to develop a new type of pickles that reduce blood pressure. Based on the outcome of these studies, a new type of fermentation bed composed of rice bran and white miso has been successfully developed. The advantage of such pickles is that they not only contain both GABA and ACE-inhibitory peptides, but also that their taste and flavor are excellent, with colors close to the original ones. The new type of pickles could temporarily reduce blood pressure in two types of rats, spontaneously hypertensive rats and NaCl-sensitive model rats. Thus, the newly developed pickles appear to be beneficial for pickle business. 相似文献
118.
Takao Takahashi Toshiharu Yagi Toyohiro Oda Irvin E. Liener 《Bioscience, biotechnology, and biochemistry》2013,77(4):865-867
(+)-Biotin was synthesized from D-glucosamine in a sequence of 13 reactions. 相似文献
119.
120.