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871.
Hitoshi Enei Hiroshi Matsui Hidetsugu Nakazawa Shinji Okumura Hideaki Yamada 《Bioscience, biotechnology, and biochemistry》2013,77(3):493-499
Reaction conditions for the synthesis of L-tyrosine or L-dopa from DL-serine and phenol or pyrocatechol were studied with intact cells of Erwinia herbicola (ATCC 21434) containing high tyrosine phenol lyase activity. The optimum pH for this reaction was around 8.0, and the optimum temperature range was between 37~40°C for the synthesis of L-tyrosine and between 15~25°C for that of L-dopa. Sodium sulfite and EDTA were added to protect the synthesized L-dopa from decomposition. As high concentrations of phenol or pyrocatechol denatured the enzyme, each substrate was fed to maintain the optimum concentration during incubation.The reaction mixture (100 ml) containing 4.0 g of DL-serine, 1.0 g of phenol or 0.7 g of pyrocatechol, 0.5 g of ammonium acetate and the cells, was incubated. During incubation, phenol or pyrocatechol was fed at intervals to maintain the substrate at the initial concentration. 5.35 g of L-tyrosine or 5.10 g of L-dopa was synthesized in 100 ml of the reaction mixture. 相似文献
872.
A method for the determination of allethrin and other pesticides in mosquito coils was developed by the combination of shaking extraction and gas chromatography (GC). Allethrin and other pesticides were adequately extracted by shaking for only half an hour with a mixture of toluene and 99% formic acid (5:1). This shaking extraction method was more effective for shortening the extraction time compared with the Soxhlet extraction method, and accurate determination was achieved without the interference from inert materials in the mosquito coils. The recovery of allethrin in various contents from the coils was 96.6 to 97.1%, with a 1.2 to 1.5% coefficient of variation. Furthermore, the recoveries of other pesticides and synergists from the coils were 94 to 102% by this shaking extraction method. 相似文献
873.
Kenji Mori Michiaki Tominaga Masanao Matsui 《Bioscience, biotechnology, and biochemistry》2013,77(8):1551-1552
Four types of amino acid related compounds were examined on their plant growth-regulating activity. These compounds were N-acylamino acids (N-acyl), N-alkylamino acids (N-alkyl), amino acid higher alkyl esters (ester) and amino acid higher alkyl amides (amide). Every compound, when the number of carbon atoms of the acyl or alkyl radical was 10 to 12, was most effective in inhibiting the root and shoot elongation of rice plant (Oryza sativa L.) in Petri dish. Ester and amide were much more effective than N-acyl and N-alkyl. Ester and amide also showed herbicidal activity against barnyardgrass (Echinochloa crusgalli) grown in pot filled with paddy soil and irrigated, especially, lauryl dl-valinate-HCl being most effective. 相似文献
874.
Yasuhiro Yamada Kota Hatano Masanao Matsui 《Bioscience, biotechnology, and biochemistry》2013,77(10):1536-1540
(±)-Lamprolobine, the (+)-enatiomer of which was isolated from the leaves of Lamprolobium fruticosum, and (±)-epilamprolobine were synthesized from δ-valerolactam. 相似文献
875.
Masayuki Sakakibara Masanao Matsui 《Bioscience, biotechnology, and biochemistry》2013,77(5):1139-1143
A newer method of the N-acylation of lactams via N-trimethylsilyl lactams is described. 相似文献
876.
Takashi Nara Hirotoshi Samejima Shukuo Kinoshita 《Bioscience, biotechnology, and biochemistry》2013,77(2):120-124
The effect of penicillin G(k) was first investigated on l-homoserine production by Micrococcus glutamicus 534-Co 147 (a threonine requiring mutant). The addition of 4 u/ml of penicillin, 7 to 9 hours after inoculation, brought about the conversion of l-homoserine to l-glutamic acid production. Similar phenomena were observed in l-lysine and l-valine fermentations. In these cases, a homoserine requiring and a leucine requiring mutant of M. glutamicus were used respectively. A marked conversion from lysine and valine to glutamate accumulation occured by penicillin addition. However, in l-isoleucine fermentation with Brevibacterium ammoniagenes ATCC 6871, no glutamate accumulation took place and isoleucine yields were remarkably decreased. 相似文献
877.
Masazumi Nihmura Soji Aomori Kenji Mori Masanao Matsui 《Bioscience, biotechnology, and biochemistry》2013,77(5):889-892
A proteinous inhibitor of lipase was purified from soybean cotyledons by the procedures of ammonium sulfate fractionation, gel-filtration on Sephadex G–150 column, DEAE-cellulose column chromatography and isoelectric focusing. The inhibitor obtained by gelfiltration was separated into three active components, D–1, D–2 and D–3, by DEAE-cellulose column chromatography. The D–3 fraction after isoelectric focusing was homogeneous judged from disc electrophoresis. The inhibitory activity was more stable against treatments of heating and Pronase when the D–3 fraction was preincubated with substrate than without substrate. The extent of inhibition was varied by changing the order of addition of reactants and condition of substrate. From these results, the mode of inhibition is discussed. 相似文献
878.
Sawao Murao Akira Goto Yoshihiro Matsui Kunio Ohyama Motoo Arai 《Bioscience, biotechnology, and biochemistry》2013,77(11):2599-2604
A screening test was carried out to obtain microbes which produce hog pancreatic α-amylase inhibitor and a new inhibitor was found in culture broth of an actinomycete, strain YM-25. This inhibitor was designated as Haim, an abbreviation for hog pancreatic α-amylase inhibitor from a microbe. The determined morphological and physiological properties of strain YM-25 led to the conclusion that the microorganism was Streptomyces griseosporeus.When the microorganism was aerobically cultured at 30°C in a jar fermentor containing the most suitable medium for growth which consisted of 5% glycerol, 0.5% polypepton, 0.2% meat extract, 0.1% yeast extract, 0.4% Na2HPO4 ? 12H2O, 0.1% KH2PO4, and 0.05% MgSO4 ? 7H2O (pH 7.3), the highest activity of Haim was obtained on 23~26hr cultivation.Haim had specific inhibitory activities against animal α-amylases but not against microbial and plant α-amylases. 相似文献
879.
Eriko Yoshizawa Mai Kaizuka Ayumi Yamagami Mieko Higuchi-Takeuchi Minami Matsui Yusuke Kakei 《Bioscience, biotechnology, and biochemistry》2013,77(3):420-429
Brassinosteroids are plant steroid hormones that regulate plant organs and chloroplast development. The detailed molecular mechanism for plant development by BR signaling is yet to be revealed, and many points regarding the relationship between BR signaling and chloroplast development remain unknown. We identify here the dominant mutant Brz-insensitive-pale green3-1D (bpg3-1D) from the Arabidopsis FOX lines that show reduced sensitivity to the chlorophyll accumulation promoted by the BR biosynthesis inhibitor, Brassinazole (Brz), in the light. BPG3 encodes a novel chloroplast protein that is evolutionally conserved in bacteria, algae, and higher plants. The expression of BPG3 was induced by light and Brz. The inhibition of electron transport in photosystem II of the chloroplasts was detected in bpg3-1D. These results suggest that BPG3 played an important role in regulating photosynthesis in the chloroplast under BR signaling. 相似文献
880.
Biochemical Studies on “Bakanae” Fungus. Part 70–71. Synthesis of Substances related to Gibberellins
Kenji Mori Tomoya Ogawa Masanao Matsui Yusuke Sumiki 《Bioscience, biotechnology, and biochemistry》2013,77(4):239-247
Several gibbane-10-carboxylic acids and esters, including methyl (±)-desoxogibberate and methyl (±))-desoxoepigibberate, were synthesized. 相似文献