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991.
Koichi Koshimizu Toshio Fujita Tetsuo Mitsui Jiro Kato 《Bioscience, biotechnology, and biochemistry》2013,77(3):221-225
1-Naphthoic acid derivatives substituted with chlorine, bromine, methyl or nitro groups at various positions of the ring were assayed for their activities in the pea straight-growth and the callus formation tests. Their growth activities are discussed from two points of view, i.e. the spatial structure hypothesis of Veldstra and the ortho reaction hypothesis advanced for benzoic acid derivatives proposed by Hansch and Muir. It appears that a combination of these two views are appropriate for the present authors’ results. 相似文献
992.
Takashi Watanabe Jiro Ohnishi Yuko Yamasaki Sumiko Kaizu Tetsuo Koshijima 《Bioscience, biotechnology, and biochemistry》2013,77(8):2233-2252
Lignin-carbohydrate complexes (LCC; nor-C-1-M, com-C-1-A) isolated from normal and compression woods of Pinus densiflora were hydrolyzed with two types of cellulase preparations, and the hydrolyzates formed were fractionated by adsorption chromatography on polyvinyl gel into water-soluble materials and LCC fragments. To elucidate the binding sites between the lignin and carbohydrate, the cellulase-degraded LCC fragments were subjected to acetylation, and then oxidation with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), which was confirmed to oxidatively cleave the benzyl ether linkages between the lignin and carbohydrate. The DDQ-oxidized fraction was then methylated by the method of Prehm, hydrolyzed, reduced and acetylated. A GC-MS analysis of the methylated sugar revealed that alditol acetates from 6-O-methyl mannose, 6-O-methyl galactose, 6-O-methyl glucose and a small amount of their 2-O- or 3-O-methyl isomers existed in both methylated fractions. 2-O-Methyl xylose and 3-O-methyl xylose were also identified in the fraction from the acidic LCC (com-C-1-A). These results led to the conclusion that acetylglucomannan and β-1,4-galactan were preferably bound to the lignin at C-6 position of the hexoses, and that arabinoglucuronoxylan did likewise at the C-2 and C-3 positions of xylose units. 相似文献
993.
994.
995.
Akihiko Matsuo Mitsuru Nakayama Tetsuo Nakamoto Yasuto Uchio Shûichi Hayashi 《Bioscience, biotechnology, and biochemistry》2013,77(4):925-927
One hundred fifty strains of actinomycetes were isolated from soils on plate cultures containing beet arabinan as the sole carbon source. About one-third of the culture fluids were found to have arabinosidase activity. A wild-type strain, Streptomyces sp. No. 17-1, was selected as the best producer of arabinosidase. The highest enzymatic activity was obtained in the culture fluid when the initial pH was adjusted to 9.0. An α-l-arabinofuranosidase was highly purified from the culture filtrate of No. 17-1 by combining column chromatography on DEAE-cellulose, gel filtration on Sephadex G-100, and isoelectric focusing. The molecular weight of the purified enzyme was estimated to be about 92, 000, and its isoelectric point was pH 4.4. The enzymatic activity was maximum at pH 6.0 and was completely inhibited by Hg2+. The apparent Km value of the enzyme for p-nitrophenyl-α-l-arabinofuranoside was determined to be 3.6 mM. 相似文献
996.
Shoji Shinomiya Kunio Yamane Touru Mizukami Fujio Kawamura Hiuga Saito 《Bioscience, biotechnology, and biochemistry》2013,77(7):1733-1735
Using a method consisting of two repetitions of “prophage transformation,” the thermostable α-amylase gene in Bacillus subtilis has been cloned in temperate phage ρ11. 相似文献
997.
Tetsuo Muro Takumi Murakami Yoshio Tominaga Shigetaka Okada 《Bioscience, biotechnology, and biochemistry》2013,77(2):607-609
We introduced efficient incorporation of unsaturated fatty acids into volicitin [N-(17-hydroxylinolenoyl)-L-glutamine] and N-linolenoyl-L-glutamine, insect-derived elicitors of plant volatiles, in the common cutworms Spodoptera litura by the incubation of larval gut tissues with unsaturated (linolenic, linoleic, and oleic acids) or saturated fatty acids (palmitic and stearic acids) sodium salt, and L-[α-15N]glutamine. 相似文献
998.
Koichi Koshimizu Satoshi Matsubara Toshiatsu Kusaki Tetsuo Mitsui 《Bioscience, biotechnology, and biochemistry》2013,77(7):795-801
A new cytokinin was isolated from methanol extracts of immature lupin seeds (Lupinus luteus) through successive purification of charcoal adsorptions, silver precipitations, ion exchange and paper chromatography. The structure was confirmed by spectral data and synthesis as (?)-6-N-(4-hydroxy-3-methylbutylamino)purine, (?)-dihydrozeatin (I). 相似文献
999.
1000.
Kazuyoshi Kawazu Makoto Inaba Tetsuo Mitsui 《Bioscience, biotechnology, and biochemistry》2013,77(4):494-506
A fish-killing component, which was named callicarpone, C20H28O4, m.p. 111°C, ?180° (chloroform) was isolated from the leaf of Callicarpa candicans and was found to have conjugated carbonyl groups, double bond and one hydroxyl group. The toxicity to fish was evaluated to be as strong as rotenone and ten times stronger than sodium pentachlorophenoxide.It was deduced from the spectral data of callicarpone (I), the tetraol (IV), the chlorohydrin (VII) and the anhydro-diacetyl derivative (II) that I was a tricarbocyclic diterpene having an ene-l,4-dione and an α-hydroxy-isopropyl attached to an oxide ring. The structure of the rearranged product obtained by treatment with sodium carbonate was established to be IX by converting it to 11-methoxy-ferruginol methyl ether. As this rearrangement was assumed to be initiated by proton abstraction by base, the structure I was required for callicarpone to explain the formation of IX. 相似文献