Research About Polysaccharide Component In Tuber Of Dioscorea Polystachya Turcz. From Jiangsu

Dioscorea polystachya Turcz., which is a tuber of yam, ranks in the genus of Dioscoreaceae. It has abundant nutrition and great edible and officinal value. The yam has the efficacy of opposite antiaging, decrease blood glucose level, enhance immune activity, decrease blood fattiness, resist tumor. Its mostly active component is the polysaccharide. The examination researched chiefly about the extraction technology, isolation, purification, structural analysis of the polysaccharide from the tuber of Dioscorea polystachya Turcz., and compared of the chemistry components in the 'Jiangsu yam' and the 'Tie-gun yam'. These results can be summarized as follows:1 The orthogonal tests were employed for optimum of extraction conditions. The result of analysis showed that the temperature of extraction was a significant factor for total polysaccharide contents, the optimum extraction technology was on 80℃ water and 1: 60 volume of water for six hours, and the content of total polysaccharide was 1.37%.2 The polysaccharide from the tuber of Dioscorea polystachya Turcz. was isolated and purified by CTAB deprotein, cellulose column and Sephadex G-100 column. The purities of polysaccharide were identified by Sephadex G-200, determination of specific rotatory power, and UV. The result of analysis showed that the polysaccharide was homogeneous, its specific rotary was 9.632°, and its UV scanning spectrum shows that there were no absorption peaks of protein and nucleic acid at point 280 nm and 260 ran.3 Paper Chromatogram analysis on acidic hydrolysates of the polysaccharide was used to determine the sugar components. The form of glycoside linkage was determined from the results of periodate oxidation, Smith degradation and IR. The result of analysis showed that the polysaccharide from the tuber of Dioscorea polystachya Turcz. was a kind of neutral heteropolysaccharide; its composed monosaccharide was identified by paper chromography as glucose(10.23%), D-mannose(10.64%) and D-galactose(8.69%); its IR spectrum...