桑黄子实体多糖的分离纯化及结构鉴定

Isolation, purification and structural elucidation of polysaccharide from the fruiting bodies of Phellinus baumii Pilát

目的:对桑黄子实体多糖进行分离纯化,并采用现代仪器分析方法对桑黄多糖的结构进行解析,为桑黄多糖的进一步应用提供理论基础。方法:桑黄子实体经水提、醇沉、冷冻干燥得水溶性多糖,经DEAE-Sepharose FastFlow离子柱和Sephacry lS-400 High Resolution凝胶柱进行分离纯化得纯多糖PBF6,采用紫外光谱、红外光谱、气相色谱、气质联用、核磁共振等技术分析桑黄多糖PBF6的结构。结果:桑黄多糖PBF6分子量为3.23×105u,不含蛋白质和核酸,糖组成研究表明PBF6仅含有葡萄糖,以1,6和1,3连接2种形式存在,其摩尔比为1:2,主链结构为→3)-β-D-Glcp-(1→3)-β-D-Glcp-(1→6)-β-D-Glcp-(1→。结论:PBF6是一种葡聚糖,建立的方法可用于多糖的分离纯化及结构分析。

Objective： To study the isolation, purification and structural elucidation of the polysaccharides from the fruiting bodies of Phellinus baumii Pilat. Methods： The process of isolating and purifying a water soluble polysaccharide PBF6 was achieved by hot water extraction, ethanol precipitation and freeze- drying. The water soluble polysaccharide was separated by chromatography on a DEAE-Sepharose Fast Flow column and Sephacryl S-400 High Resolution column. The structural of polysaccharide was elucidated by UV, IR, GC, GC-MS and NMR. Results： The molecular weight of PBF6 was 3.23×10 u. Sugar analysis showed this polysaccharide was composed of glucose only. Methylation analysis revealed 1,6-1inked Glcp and 1,3-1inked Glcp in a molar ratio of 1.0：2.0. NMR analysis further showed that the structure consist mainly of a backbone of （1,3）-Iinked-D-glucopyranosyl residues and （1,6）-Iinked-D- glucopyranosyl residues with the following structure： →3）-β-D-Glcp-（1→3）-β-D-Glcp-（1→6）-β-D-Glcp Conclusion： PBF6 was a glucan. The established method can be used to purify and structure analysis of the polysaccharides.