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Water-soluble polysaccharides and pectin substances have been isolated from various organs ofA. neglectus and their quantitative amounts and monosacchardie compositions have been determined. Native acetylated glucomannans (A, B, and C) containing 13, 15, and 20% of acetyl groups and being homogeneous according to the results of gel chromatography have been isolated from the roots. On the basis of the results of periodate oxidation, methylation, and IR spectroscopy it has been established that the neutral polysaccharides of the roots ofA. neglectus is a mixture of three glucomannans consisting of -14 linear-bound D-gluco- and D-mannopyranose residues.Deceased.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 702–706, November–December, 1981.  相似文献   

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The polysaccharides of the tuberous roots ofBiebersteinia multifida D. C. have been isolated and characterized. The neutral polysaccharide consists of a mixture of three glucans — A, B, and C — with molecular weights of 4100, 2200, and 1100, respectively, formed by D-glucopyran residues linked by bonds.Deceased.Institute of the Chemistry of Plants Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 755–757, November–December, 1985.  相似文献   

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Summary 1. The amounts of glucofructans in 15 species of plants of the genusAllium L. growing in Central Asia have been studied.2. The polydispersity of all the glucofructans isolated has been established. Fractionation of the glucofructan fromA. sativum L. yielded homogeneous fractions with mol. wt. 1900 and 5000. On the basis of their IR spectra and the results of periodate oxidation, they have been assigned to the glucofructans of the inulin type.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 137–142, March–April, 1979.  相似文献   

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The polysaccharides of the tuberous roots ofBiebersteinia multifida D. C. have been isolated and characterized. The neutral polysaccharide consists of a mixture of three glucans — A, B, and C — with molecular weights of 4100, 2200, and 1100, respectively, formed by D-glucopyran residues linked by α bonds.  相似文献   

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Water-soluble polysaccharides have been isolated from two species ofEremurus — E. lactiflorus andE. luteus — with yields of 13.5% and 20.5%, respectively. They contained mainly glucose and mannose in ratios of 1:5 and 1:3.1. The polysaccharides ofE. lactiflorus were separated from a column of DEAE-cellulose. The yield of neutral fraction was 10.3%. Gel filtration of the polysaccharides on Sephadex G-200 showed their polydispersity. Homogeneous fractions were obtained by fractional precipitation with ethanol. They have been characterized with respect to monosaccharide composition, molecular weight, and IR spectra.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 604–608, September–October, 1979.  相似文献   

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Water-soluble polysaccharides and pectin substances have been isolated from various organs ofA. neglectus and their quantitative amounts and monosacchardie compositions have been determined. Native acetylated glucomannans (A, B, and C) containing 13, 15, and 20% of acetyl groups and being homogeneous according to the results of gel chromatography have been isolated from the roots. On the basis of the results of periodate oxidation, methylation, and IR spectroscopy it has been established that the neutral polysaccharides of the roots ofA. neglectus is a mixture of three glucomannans consisting of β-1→4 linear-bound D-gluco- and D-mannopyranose residues.  相似文献   

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Several fractions of alkali-soluble polysaccharides have been isolated from the seeds ofIris sogdiana Bge. The separation of one of the fractions has yielded a glucomannan consisting of glucose and mannose residues in a ratio of 1:1.2. On the basis of the results of oxidation with chromium trioxide of the acetate of the glucomannan, and of periodate oxidation and methylation, it has been established that its molecule consists of a linear chain composed of -D-glucopyranose and -D-mannopyranose residues connected by -14 bonds, although the presence of branching is not excluded. The possibility has been shown of isolating D-mannose by the hydrolysis of the seeds.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 466–471, July–August, 1979.  相似文献   

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Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (3712) 89 14 75. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 313–314, March–April, 1995. Original article submitted November 7, 1994.  相似文献   

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Human calcitonin. I. Isolation and characterization   总被引:1,自引:0,他引:1  
Two highly active calcitonin peptides, M with 32 amino acids, and D a dimer of M, were isolated from a large human mediastinal C cell tumour. D can easily be transformed into M by the action of 1N ammonia; D and M afford two different sulphoxides, but all four peptides yield the same product upon oxidation with performic acid. Both D and M have a potency of about 120 MRC units/mg dry weight; their sulphoxides, by contrast, are almost inactive. Tryptic digestion of M produces an N-terminal octadecapeptide (TrI) and a C-terminal tetradecapeptide (TrII), the latter being also obtained from D. Amino acid analysis and other analytical data are presented. The structure of the human calcitonin peptides D and M is thus very different from that of porcine α-thyrocalcitonin.  相似文献   

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A phytotoxic PLPC has been isolated from the mycelium of the fungusVerticillium dahliae Kleb., strain 614. The polysaccharide component has been split out from the PLPC by mild acid hydrolysis. The polysaccharide has been fractionated and the monosaccharide compositions of the fractions have been determined. A phytotoxic polysaccharide homogeneous according to gel chromatography and chromatography on DEAE-cellulose has been isolated which consists of an -glucan containing a minor amount of D-glucosamine.Tashkent State University. All-Union Scientific-Research Institute of Agricultural Microbiology, Leningrad. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 774–777, November–December, 1979.  相似文献   

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Water-soluble polysaccharides, pectin substances, and hemicelluloses have been isolated from the epigeal part ofLagochilus zeravschanicus and characterized. The pectins isolated are characterized by a high degree of esterification of the carboxy groups, and their base consists of a fragment constructed from -14-linkedD-galacturonic acid residues.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (3712) 40 64 75. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 569–572, July–August, 1997.  相似文献   

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Ten oligosaccharides have been isolated from the products of the partial hydrolysis of a native acetylated glucomannan obtained fromEremurus lactiflorus O. Fedtsch. Their structures have been studied with the aid of acid hydrolysis before and after reduction with NaBH4, by the GLC method, and also by chromatography with markers. The compositions and sequence of the monomers in tetra- and heptaoligo-saccharides have been determined by the13C NMR method. The glucommannan ofE. lactiflorus differs from theEremurus glucomannans studied previously by the ratio of monosaccharides, the presence of 0-Ac groups, the degree of polymerization, and the presence of a cellobiose unit (Glcp-Glcp) in the polymer chain. The repeating unit consists of 14 hexose residues.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 680–684, November–December, 1982.  相似文献   

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