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91.
Tomoyuki Tsuneya Masakazu Ishihara Haruyasu Shiota Minoru Shiga 《Bioscience, biotechnology, and biochemistry》2013,77(11):2495-2502
Steam distilled oil of quince fruit (Cydonia oblonga Mill.=C. vulgaris Pers., marmelo in Japanese) was analyzed by gas chromatography and gas chromatography-mass spectrometry. Sixty-two compounds, 2 hydrocarbons, 13 esters, 11 alcohols, 11 aldehydes, 11 ketones, 5 lactones and 9 miscellaneous compounds, were identified. Of them, the chemical structures of two new oxide compounds, trans- and cis-3-methyl-5-[(E)-3′-methyl-13′-butadien-1′-yl]tetrahydrofuran, were elucidated by instrumental analyses. 相似文献
92.
The glucomannan isolated from larch holocellulose was hydrolyzed by a purified endo-d-β-mannanase. The products were fractionated by gel filtration on a Polyacrylamide gel in water and partition chromatography on ion exchange resins in 80% ethanol. The following oligosaccharides were isolated and identified: (a) 4-O-β-d-Manp-d-Man, (b) 4-O-β-d-Glcp-d-Man, (c) 4-O-β-d-Glcp-d-Glc, (d) O-β-d-Manp-(1 →4)-O-β-d-Manp-(1 →4)-d-Man, (e) O-β-dGlcp-(l →4)-O-β-d-Manp-(l →4)-d-Man, (f) O-β-d-Manp-(l →4)-Oβ-d-Glcp-(l →4)-d-Man, (g) O-β-d-Manp-(l →4)-O-[α-d-Galp-(l →6)]-d-Man, (h) O-β-d-Manp-(l →4)-O-β-d-Manp-(l →4)-O-β-d-Manp-(l →4)-d-Man, and (i) O-β-d-Glcp-(1 →4)-O-β-d-Manp-(1 →4)-O-β-d-Manp-(1 →4)-d-Man. 相似文献
93.
94.
Takehiko Yamamoto Junichi Kumada Teruo Sawai 《Bioscience, biotechnology, and biochemistry》2013,77(3):185-191
The purification of yeast invertase was attempted by application of the chromatographic method using Duolite C-10, a sulfonic acid cation exchange resin. This method was found to be extremely simple in process and significantly effective for the improvement of purity of the enzyme, compared with those other methods reported, hitherto. In the present paper, the procedure of the purification and some properties of the enzyme obtained thereby, are described, and some discussion of the implications is presented. 相似文献
95.
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
96.
Keita Nishiyama Akira Kawanabe Hirofumi Miyauchi Fumiaki Abe Daigo Tsubokawa Kazuhiko Ishihara 《Bioscience, biotechnology, and biochemistry》2013,77(8):1444-1451
The aim of this study was to assess the adhesion of Bifidobacterium strains to acidic carbohydrate moieties of porcine colonic mucin. Mucins were extracted and purified via gel filtration chromatography followed by density-gradient ultracentrifugation. The presence of sulfated and sialylated carbohydrates in mucins was shown by enzyme-linked immunosorbent assays using PGM34 and HMC31 monoclonal antibodies (mAbs), respectively. Adhesion of Bifidobacterium strains to mucin preparations was markedly affected by the degree of purification. In eight of 22 strains, we observed increased adhesion to mucin preparations purified by ultracentrifugation. Moreover, in some of these eight strains, adhesion to mucin was reduced by pretreatment with sulfatase and/or sialidase, and competitively inhibited by pretreatment with PGM34 and/or HCM31 mAbs. Our results showed that some Bifidobacterium strains adhered to sulfo- and/or sialomucin and were able to recognize carbohydrate structures of the mAbs epitopes. 相似文献
97.
Junichi Ueda Takao Yokota Nobutaka Takahashi Michio Yoshida Jiro Kato 《Bioscience, biotechnology, and biochemistry》2013,77(12):3083-3086
A root growth-promoting factor was isolated from Artemisia capillaris Thunb. The chemical structure of this compound was elucidated as methyl 3-(3-methylbut-2-enoyl)-4-hydroxycinnamate (capillarol) on the basis of its spectroscopic analysis. At 5×10–4m this compound promoted rice root growth to 180% of the control value. 相似文献
98.
Molecular dynamics (MD) simulations using all-atom and explicit solvent models provide valuable information on the detailed behavior of protein–partner substrate binding at the atomic level. As the power of computational resources increase, MD simulations are being used more widely and easily. However, it is still difficult to investigate the thermodynamic properties of protein–partner substrate binding and protein folding with conventional MD simulations. Enhanced sampling methods have been developed to sample conformations that reflect equilibrium conditions in a more efficient manner than conventional MD simulations, thereby allowing the construction of accurate free-energy landscapes. In this review, we discuss these enhanced sampling methods using a series of case-by-case examples. In particular, we review enhanced sampling methods conforming to trivial trajectory parallelization, virtual-system coupled multicanonical MD, and adaptive lambda square dynamics. These methods have been recently developed based on the existing method of multicanonical MD simulation. Their applications are reviewed with an emphasis on describing their practical implementation. In our concluding remarks we explore extensions of the enhanced sampling methods that may allow for even more efficient sampling. 相似文献
99.
Kyoko Hosohama-Saito Eitoyo Kokubu Kazuko Okamoto-Shibayama Daichi Kita Akira Katakura Kazuyuki Ishihara 《PloS one》2016,11(1)
Capnocytophaga ochracea is present in the dental plaque biofilm of patients with periodontitis. Biofilm cells change their phenotype through quorum sensing in response to fluctuations in cell-population density. Quorum sensing is mediated by auto-inducers (AIs). AI-2 is involved in intercellular signaling, and production of its distant precursor is catalyzed by LuxS, an enzyme involved in the activated methyl cycle. Our aim was to clarify the role of LuxS in biofilm formation by C. ochracea. Two luxS-deficient mutants, TmAI2 and LKT7, were constructed from C. ochracea ATCC 27872 by homologous recombination. The mutants produced significantly less AI-2 than the wild type. The growth rates of these mutants were similar to that of the wild-type in both undiluted Tryptic soy broth and 0.5 × Tryptic soy broth. However, according to crystal violet staining, they produced significantly less biofilm than the wild type. Confocal laser scanning microscopy and scanning electron microscopy showed that the biofilm of the TmAI2 strain had a rougher structure than that of the wild type. Complementation of TmAI-2 with extrinsic AI-2 from the culture supernatant of wild-type strain did not restore biofilm formation by the TmAI2 strain, but complementation of LKT7 strain with luxS partially restored biofilm formation. These results indicate that LuxS is involved in biofilm formation by C. ochracea, and that the attenuation of biofilm formation by the mutants is likely caused by a defect in the activated methyl cycle rather than by a loss of AI-2. 相似文献
100.
Izumi Uno Takashi Kozaka Daisuke Miwa Yoji Kitamura Mohammad Anwar-ul Azim Kazuma Ogawa Junichi Taki Seigo Kinuya Kazuhiro Shiba 《PloS one》2016,11(1)