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AIM To study the structural characterization of an acidic polysaccharide, H3, isolated from the seeds of Cuscuta chinensis Lam. METHODS Both chemical (such as sugar component analysis, methylation analysis, reduction of uronic acid, partial acidic hydrolysis, etc.) and spectral analysis (1HNMR, 13CNMR, IR, etc.) were used to investigate the structural characterization of H3. RESULTS The molecular weight of H3 was estimated to be more than 1.0×106. The analytical results of sugar components indicated that H3 composed of Rha, Ara, Gal, and Gal A. Methylation analysis, partial acidic hydrolysis and 1H, 13CNMR further identified the linkages and sequence of the residues of H3. CONCLUSION These results suggest that H3 is a highly branched heteropolysaccharide with structure elucidation for the first time.
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The application of electron impact, chemical ionization , fast atom bombardment, electro-spray ionization, matrix-assisted laser desor ption ionization and tandem mass spectrometry in the structural analysis of sacc harides was reviewed, 53 papers were cited.
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Object To study the polysaccharides from Salvia chinensis Benth. Methods DEAE-cellulose and gel-filtration chromatography were used to isolate and purify the polysaccharides whose structures were characterized by using chemical and spectral methods. Results Two homogeneous polysaccharides,named SC5 and SC6,were obtained from the water and diluted-alkaline extract,respectively,with their molecular weights estimated by HPGPC to be 4.8?10 4 and more than 1.0?10 6. Both structures were investigated to be complicated acidic polysaccharides. Conclusion The two polysaccharides are obtained for the first time from this plant.
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Object Polysaccharide constituents in the seed of Cuscuta chinensis Lam were investigated Methods Individual constituent was isolated and purified by DEAE cellulose and gel filtration chromatography, and its structural features were further studied by physicochemical constants, and spectral analysis Results Two polysaccharides, named H6 and H8, were obtained from alkalescent or boiling water extract fractions, respectively The molecular mass of H6 was 3 14?10 5 and that of H8 was more than 1 0?10 6 Both structures were found to be complex neutral heteropolysaccharides composed of Ara, Rha, Gal and Xyl Conclusion These polysaccharides were obtained from this plant for the first time
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Object To develop a simple and reliable method to detect the presence of uronic acids in polysaccharides Methods Uronic acid containing polysaccharides and standard glucons were subjected to acid hydrosis for 2 h and 4 h respectively. Samples of the products, before and after hydrolysis were analyzed by TLC using standard uronic acid as the control and aminobenzen alizaric acid as the chromogenic agent, to compare the sensitivities in the detection of uronic acid used in the present conventional analysis. Results The fluorescent spots used as criterion in traditional TLC method were not shown by uronic acids, but by CF 3COOCH 3 and other by products in reaction 0 5 ?g of uronic acid could be detected with our method, without false positive reaction Conclusion The traditional TLC method seemed to lack theorectical background and may mislead structural study The present method in more reliable to detect uronic acids in polysaccharides by analyzing the complete hydrolytic products of polysaccharides using TLC with standard uronic acids as control and aminobenzene alizaric acid as chromogenic agent