山药多糖的提取分离和结构测定

Extraction, Isolation and Structural Determination of the Polysacchrides from Dioscorea opposita

目的 :提取分离并测定山药多糖的结构。方法 :依次用水提取 ,乙醇和十六烷基三甲基溴胺盐沉淀法得到粗多糖 ;用葡聚糖凝胶柱层析和高效液相层析纯化多糖并测定分子量 ;甲基化分析和薄层层析分析多糖酸水解产物 ,结合IR和13 CNMR确定单糖组成、连接方式和端基碳构型。结果 :从山药中得到两个均一多糖S1和S2 。结论 :S1和S2 的分子量分别为 6 30 0 0和 74 0 0Dal,它们均为 [α D Glc(1→ 4 )

AIM:To isolate and determine the structures of polysaccharides from Dioscorea opposite. METHOD: Having obtained crude polysaccharides with water extraction, alcohol and CTAB precipitation successively, gel column chromatography on Sephadex G-100 and HPLC analysis were subjected to purify the polysaccharides and determine their molecular weights. Methylation and TLC analysis on their acidic hydrolysates, together with IR and 13CNMR, were used to determine the sugar components, glycosyl linkages and configuration of anomeric carbons. RESULT:Two homogenous polysaccharides were isolated from the root of Dioscorea opposita. CONCLUSION: The molecular weights of S 1 and S 2 were 63?000 and 7?400 Dal respectively. They are all glucans with such type as [α-D-Glc(1→4)-] n