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1.
Shintaro Kamiya Sachiko Esaki Naoko Shiba 《Bioscience, biotechnology, and biochemistry》2013,77(8):2207-2214
To investigate the substrate specificity of β-l-rhamnosidase, the following β-l-rhamnopyranosides were synthesized: 1-(β-l-rhamnopyranosyl)-dl-glycerol (1), methyl β-l-rhamnopyranoside (2), methyl 2-O-(β-l-rhamnopyranosyl)-β-d-glucopyranoside (3) and methyl 2-O-β(β-l-rhamnopyranosyl)-α-l-arabinopyranoside (4). The synthesis of 3 was performed using l-quinovose with neighboring group participation, which lead stereoselectively to the β-l-quinovoside. The 2-OH of the l-quinovo-unit was selectively deblocked, oxidized to the keto group, and then stereoselectively reduced, whereby 3 was produced. 相似文献
2.
The electrophoretically homogeneous glucomannan isolated from konjac flour was composed of d-glucose and d-mannose residues in the approximate ratio of 1: 1.6. Controlled acid hydrolysis gave 4-O-β-d-mannopyranosyl-d-mannose, 4-O-β-d-mannopyranosyl-d-glucoseT 4-O-β-d-glucopyranosyl-d-glucose(cellobiose), 4-O-β-d-glucopyranosyl-d-mannose(epicellobiose), O-β-d-mannopyranosyl-(1→4)-O-β-d-mannopyranosyl-(1→4)-d-mannose, O-β-d-glucopyranosyl- (1→4)-O-β-d-mannopyranosyl-(1→4)-d-mannose, O-β-d-mannopyranosyl-(1→4)-O-β-d-glucopy- ranosyl-(1→4)-d-mannose and O-β-d-glucopyranosyl-(1→4)-O-β-d-glucopyranosyl-(1→4)-d-mannose. 相似文献
3.
A glucomannan isolated from konjac flour was hydrolyzed with commercially available crude and purified cellulases. The following oligosaccharides were isolated from the hydrolyzate and identified: (a) 4-O-β-d-mannopyranosyl-d-monnose (b) 4-O-β-d-mannopyranosyl-d-glucose (c) O-β-d-mannopyranosyl-(1→4)-O-β-d-mannopyranosyl-(1→4)-d-mannose (d) O-β-d-mannopyranosyl-(1→4)-O-β-d-mannopyranosyl-(1→4)-d-glucose (e) O-β-d-mannopyranosyl-(1→4)-O-β-d-mannopyranosyl-(1→4)-O-β-d-mannopyranosyl-(1→4)-d-mannose (f) O-β-d-mannopyranosyl-(1→4)-O-β-d-mannopyranosyl-(1→4)-O-β-d-mannopyranosyl-(1→4)-d-glucose (g) O-β-d-mannopyranosyl-(1→4)-O-β-d-mannopyranosyl-(1→4)-O-β-d-mannopyranosyl-(1→4)-O-β-d-mannopyranosyl-(1→4)-d-glucose (h) 4-O-β-d-glucopyranosyl-d-glucose(cellobiose) (i) 4-O-β-d-glucopyranosyl-d-mannose (epicellobiose) (j) O-β-d-glucopyranosyl-(1→4)-O-β-d-mannopyranosyl-(1→4)-d-mannose. Of these saccharides, (h), (i) and (j) were isolated from the hydrolyzate by purified cellulase, while (g) was isolated from the hydrolyzate by crude cellulase. The others were all present in the hydrolyzates both by crude and by purified cellulases. 相似文献
4.
Acremonium sp. 15 a fungus isolated from soil, produces an extracellular enzyme system degrading cyclic (1→2)-β-d-glucan. This enzyme was found to be a mixture of endo-(1→2)-β-d-glucanase and β-d-glucosidase. The (1→2)-β-d-glucanase was purified to homogeneity shown by disc-electrophoresis after SP-Sephadex column chromatography, Sephadex G-75 gel filtration, and rechromatography on SP-Sephadex. The molecular weight of the enzyme was 3.6 × 104 by SDS-polyacrylamide gel electrophoresis. The isoelectric point of the enzyme was pH 9.6. The enzyme was most active at pH 4.0—4.5, and stable up to 40°C in 20 mm acetate buffer (pH 5.0) for 2 hr of incubation. This enzyme hydrolyzed only (l→2)-β-d-glucan and did not hydrolyze laminaran, curdlan, or CM-cellulose. The hydrolysis products from cyclic (1→2)-β-d-glucan were mainly sophorose.The β-d-glucosidase was purified about 4000-fold. The rate of hydrolysis of the substrates by this β-d-glucosidase decreased in the following order: β-nitrophenyl-β-d-glucoside, sophorose, phenyl-β-d-glucoside, laminaribiose, and salicin. This enzyme has strong transfer action even at the low concentration of 0.75 mm substrate. 相似文献
5.
Fumio Yagi Kenjiro Tadera Akira Kobayashi 《Bioscience, biotechnology, and biochemistry》2013,77(10):2985-2990
transglucosylation by a β-d-glucosidase from cycad seeds. These azoxyglycosides, named neocycasin H, I, and J, were identified as O-β-d-glucopyranosyl-(1→4)-O-β-d-glucopyranosyl-(l→3)-O-β-d-glucopyranoside of methylazoxymethanol (MAM), O-β-d-glucopyranosyl-(1→3)-[O-β-d-glucopyranosyl-(1→6)]-O-β-d-glucopyranoside of MAM, and O-β-d-glucopyranosyl-(1→3)-[O-β-d-xylopyranosyl-(1→6)]-O-β-d-glucopyranoside of MAM, respectively. On the basis of their structures, the mechanism of the formation of these neocycasins is also discussed. 相似文献
6.
Koya Kawano Kazuki Sakai Hiroji Sato Sadao Sakamura 《Bioscience, biotechnology, and biochemistry》2013,77(10):1999-2002
During an examination of components contributing to the bitter taste of asparagus bottom cut (Asparagus officinalis L.), two new furostanol saponins were isolated from roots extractives. Their chemical structures were established as 5β-furostane-3β,22,26 triol-3-O-β-d-glucopyranosyl (1→2)-β-d-glucopyranoside 26-O-β-d-glucopyranoside and 5β-furostane-3β,22,26 triol-3-O-β-d-glucopyranosyl (1→2) [β-d-xylopyranoxyl (1→4)]-β-d-glucopyranoside 26-O-β-d-glucopyranoside respectively. 相似文献
7.
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
8.
Rubusoside derivatives by transgalactosylation of various β-galactosidases were isolated and their structures were analyzed. Escherichia coli β-galactosidase produced mainly 13-O-β-d-glucosyl-19-O-[β-d-galactosyl-(1→6)-β-d-glucosyl]-steviol (RGal-2). Bacillus circulans β-galactosidase produced mainly 13-O-β-d-glucosyl-19-O-[β-d-galactosyl-(1→4)-β-d-glucosyl]-steviol (RGal-1a) in the early stage of the reaction and then produced 13-O-[β-d-galactosyl-(1→4)-β-d-glucosyl]-19-O-β-d-glucosyl-steviol (RGal-1b). With decreasing the amount of these products (RGal-1a and RGal-1b), RGal-2 was produced. 相似文献
9.
《Nucleosides, nucleotides & nucleic acids》2013,32(5-8):751-753
Abstract 9-(3-Deoxy-β-d-erythro-pentofuranosyl)-2,6-diaminopurine (2) was synthesized by an enzymatic transglycosylation of 2,6-diaminopurine using 3′-deoxycytidine (1) as a donor of the sugar moiety. Nucleoside 2 was transformed to 3′-deoxy guanosine (3), 9-(3-deoxy-β-d-erythro-pentofuranosyl)-2-amino-6-oxopurine (3′-deoxyisoguanosine; 4), and 9-(3-deoxy-β-d-erythro-pentofuranosyl)-2-fluoroadenine (5). Compounds 2–5 were evaluated for their anti-HIV activity. 相似文献
10.
Ryutaro Utsumi 《Bioscience, biotechnology, and biochemistry》2013,77(8):2129-2130
The substrate specificity of α-d-xylosidase from Bacillus sp. No. 693–1 was further investigated. The enzyme hydrolyzed α-1,2-, α-1,3-, and α-1,4-xylobioses. It also acted on some heterooligosaccharides such as O-α-d-xylopyranosyl-(1→6)-d-glucopyranose, O-α-d-xylopyranosyl-(1→6)-O-β-d-glucopyranosyl-(1→4)-d-glucopyranose, O-α- d-xylopyranosyl-(1→6)-O-d-glucopyranosyl-(1→4)-O-[α-d-xylopyranosyl-(1→6)]-d-glucopyranose, and O-α-d-xylopyranosyl-(1→3)-l-arabinopyranose. The enzyme was unable to hydrolyze tamarinde polysaccharides although it could hydrolyze low molecular weight substrates with similar linkages. 相似文献
11.
A xyloglucan (MBXG) from the cell walls of etiolated mung bean hypocotyls was characterized by analyzing the fragment oligosaccharides from controlled degradation products of the polymer with acid and enzyme.Cellobiose, cellotriose and cellotetraose were isolated from the partial acid hydrolyzate of MBXG. Isoprimeverose (6-O-α-d-xylopyranosyl-d-glucopyranose) and a pentasaccharide, α-l-fucosyl-(1 → 2)-β-d-galactosyl-(1 → 2)-α-d-xylosyl-(1 → 6)-β-d-glucosyl-(1 → 4)-d-glucose, were isolated from the hydrolyzate of MBXG with an Asp. oryzae enzyme preparation. 相似文献
12.
Akira Hasegawa Shuichi Hara Makoto Kiso Ichiro Azuma 《Bioscience, biotechnology, and biochemistry》2013,77(8):2095-2099
A variety of the lipophilic derivatives at C-1 and C-6 in N-[2-O-(2-acetamido-2,3-dideoxy-1-thio-β-d-glucopyranose-B-yl)-d-lactoy]-l-alanyl-(N1-fatty acyl)-d-isoglutamine methyl esters were synthesized from 2N-acetyl-1-S-acetyl-4,6-O-isopropylidene-1-thiomuramoyl-l-alanyl-d-isogluta-mine methyl ester. Their immunoadjuvant activity in guinea-pigs, and the protective effect in mice infected with Escherichia coli (E-77156) were examined. 相似文献
13.
Teruo Amachi Shoji Imamoto Hajime Yoshizumi 《Bioscience, biotechnology, and biochemistry》2013,77(8):1222-1230
A growth factor (TJF) for a malo-lactic fermentation bacterium has been isolated from tomato juice, and found to be a β-glucoside. The NMR spectra of TJF and its acetate revealed that the glucosyl residue linked to the hydroxyl group at C-2′ or C-4′ of d- or l-pantothenic acid moiety. Then, 2′-O-(β-d-glucopyranosyl)-dl-pantothenic acid (I), 4′-O-(β-d-glucopyranosyl)-dl-pantothenic acid (II) and 4′-O-(β-d-glucopyranosyl)-d(R)-pantothenic acid (II-a) were synthesized, and Il-a and 4′-O-(β-d-glucopyranosyl)-l-pantothenic acid (II-b) were obtained by the optical resolution of the acetate of II. Among the above compounds, II-a was identical with natural TJF regarding to the biological activity, NMR and ORD spectra, and thin-layer chromatography. 相似文献
14.
Kenji Sakai Takashi Tachki Hidehiko Kumagai Tatsurokuro Tochkura 《Bioscience, biotechnology, and biochemistry》2013,77(9):2287-2293
Two β-d-glucosidases were purified to homogeneity from Bifidobacterium breve 203: one ( β-d-glucosidase I; molecular weight, 96,000) showed reactivity toward p-nitrophenyl (p-NP) β-d-fucoside, 74% of that to p-NP β-d-glucoside, and the other ( β-dglucosidase II; molecular weight, 450,000) did not. They also differed in their thermal and pH stabilities. Laminaribiose, cellobiose and gentiobiose were hydrolyzed by β-d-glucosidase I, with 53%, 34% and 3% of the reactivity in the case of p-NP β-d-glucoside, and by β-dglucosidase II, with 53%, 6% and 107% of the reactivity. The reaction of β-dglucosidase I with p-NP β-dfucoside was enhanced by the addition of glucose and other monosaccharides to the reaction mixture, whereas that with p-NP β-dglucoside was not affected. The activity of β-dglucosidase II with p-NP β-dglucoside was inhibited by glucose. 相似文献
15.
《Bioscience, biotechnology, and biochemistry》2013,77(3):560-565
Partial acid hydrolysis of Saccharomyces cerevisiae mannan gave 2-O-α-d-Manp-d-Man (1), 3-O-α-d-Manp-d-Man (2), 6-O-α-d-Manp-d-Man (3), O-α-d Manp-(1→2)O-α-d-Manp-(1→2)-d-Man (4), O-α-d-Manp-(1→2)-O-α-d-Manp-(1→6)-d-Man (5), O-α-d Manp-(1→6)-6-O-α-d-Manp-(1→6)-d-Man (6), O-α-d Manp-(1→2)-O-α-d-Manp-(1→2)-6-O-α-d-Manp-(1→6)-d-Man (7), O-α-d-Manp-(1→2)-O-α-d-Manp-(1→6)-O-α-d-Manp-(1→6)-d-Man (8), and O-α-d-Manp-(1→6)-O-[α-d-Manp-(1→2)]-O-α-d-Manp-(1→6)-d-Man (9). 相似文献
16.
Sonoe Ochiai Yanagi Masako Kito Maria A. M. Galeazzi 《Bioscience, biotechnology, and biochemistry》2013,77(10):2561-2563
The acylated, amidated and esterified derivatives of N-acetylglucosaminyl-α(1 → 4)-N-acetylmuramyl tri- and tetrapeptide were synthesized and examined as to their protective effect on pseudomonal infection in the mouse and pyrogenicity in the rabbit. Modifications of the terminal end function of the peptide moieties in their molecules caused enhancement of resistance to pseudomonal infection and reduction of pyrogenicity. Among the compounds tested, sodium N-acetylglucosaminyl-β(1 → 4)-N-acetylmuramyl-l-alanyl-d-isoglutaminyl-(l)-stearoyl-(d)-meso-2,6-diaminopimelic acid-(d)-amide and sodium N-acetylglucosaminyl-β(1 → 4)-N-acetylmuramyl-l-alanyl-d-isoglutaminyl-(l)-stearoyl-(d)-meso-2,6-diaminopimelic acid-(d)-amide-(l)-d-alanine were found to be advantageous and conceivably worthwhile for further investigation as immunobiologically active compounds. 相似文献
17.
Shintaro Kamiya Sachiko Esaki Reiko Ito-Tanaka 《Bioscience, biotechnology, and biochemistry》2013,77(8):2251-2358
To investigate the substrate specificity of α-l-rhamnosidase from Aspergillus niger, the following seven substrates were synthesized: methyl 3-O-α-l-rhamnopyranosyl-α-d-mannopyranoside (1), methyl 3-O-α-l-rhamnopyranosyl-α-l-xylopyranoside (2), methyl 3-0-α-l-rhamnopyranosyl-α-l-rhamnopyranoside (3), methyl 4-0-α-l-rhamnopyranosyl-α-d-galactopyranoside (4), methyl 4-O-α-l-rhamnopyranosyl-α-d-mannopyranoside (5), methyl 4-0-α-l-rhamnopyra-nosyl-α-d-xylopyranoside (6), and 6-0-β-l-rhamnopyranosyl-d-mannopyranose (7). Compounds 1~6 were well-hydrolyzed by the crude enzyme, but 7 was unaffected. 相似文献
18.
A new procedure which involves 1-trichloroacetyl sugars as the starting material has been developed for the synthesis of purine nucleosides. 7-β-d-Glucopyranosyl-, 7-β-d-xylopyranosyl-, 7-β-d-ribopyranosyl-theophylline, 9-(tetra-O-acetyl-β-d-glucopyranosyl)-2,6,8-trichloropurine and 9-β-d-glucopyranosyl adenine were prepared in good yields by the reaction in fusion of purine bases with 1-trichloroacetyl sugars, using zinc chloride, p-toluenesulfonic acid, or ethyl polyphosphate as catalyst. 9-d-Ribofuranosyl adenine was also prepared by the same procedures, although the anomeric configuration of the compound is not yet definite. The effect of catalysts on the yields of purine nucleosides is discussed. 相似文献
19.
The transxylosylation reaction products of β-xylosidase-1, excreted by Penicillium wortmanni IFO 7237 using β-(1→4)-xylobiose as substrate, have been separated by chromatography on activated charcoal into four fractions, designated as P-1, P-2, P-3, and P-4, respectively. They were further purified by preparative paper chromatography. The characterization and structural analysis were done by measurement of the degree of polymerization (DP) and specific rotation followed by methylation analysis. Moreover, the enzymatic structural analysis of transxylosylation products, with high performance liquid chromatography (HPLC), allowed the confirmation of each structure. The first product, P-1, was β-(1→3)-xylobiose and the second, P-2, was β-(1→4)-xylotriose, but, P-3 was O-β-d-xylopyranosyl-(1→3)-O-β-d-xylopyranosyl-(1→4)-d-xylopyranose or isomeric xylo-triose and P-4 was assumed to be O-β-d-xylopyranosyl-(1→4)-[O-β-d-xylopyranosyl-(1→3)]-O-β-d-xylopyranosyl-(1→4)-d-xylopyranose. 相似文献
20.
Harukazu Fukami Shoji Ikeda Hideki Kohno Minoru Nakajima 《Bioscience, biotechnology, and biochemistry》2013,77(12):2383-2388
Methyl 2,5-di-O-p-nitrobenzoyl-β-d-ribofuranoside was prepared via methyl 2,3-O-ethoxyethylidene-β-d-ribofuranoside from d-ribose. It was condensed with 3,4,6-tri-O-acetyl-2-deoxy-2-(2′,4′-dinitroanilino)-α-d-glucopyranosyl bromide and 3,4-di-O-acetyl-2,6-dideoxy-2-(2′,4′-dinitroanilino)-6-phthalimido-α-d-glucopyranosyl bromide by a modified Königs-Knorr reaction to give neobiosamine analogs. The condensation reaction gave α-glucosides as the minor product, and the corresponding β-glucoside as the major product. 相似文献