山茱萸酸性多糖FCP5-A的分离纯化与结构表征

从山茱萸中提取出水溶性粗多糖, 经柱色谱分离纯化得到一种酸性多糖组分FCP5-A. 采用高效凝胶渗透色谱法(HPGPC)测定其为均一性多糖, 平均分子量为8.7×104. 经IR、GC、部分酸水解、13C NMR及甲基化分析等方法对该多糖的化学结构进行了表征. 结果表明, 该多糖由鼠李糖、阿拉伯糖、半乳糖及半乳糖醛酸组成, 其摩尔比为1∶5.7∶0.6∶1.2. FCP5-A为多分支结构, 由-2)Rha(1-及-4)GalA(1-构成主链, 在鼠李糖的4位存在分支; 支链主要由高度分支的阿拉伯糖构成, 此外还存在-3)Gal(1-; 末端残基为Ara(1-及Gal(1-. 结果提示, FCP5-A为一种新的山茱萸酸性分支多糖.

Isolation and Purification and Structural Characterization of Acidic Polysaccharide FCP5-A from Fruit of Cornus officinalis

Fruit of Cornus officinalis has been used in Chinese traditional medicine for over two thousand of years. Polysaccharides, as important components of Cornus officinalis, have attracted much attention. An acidic polysaccharide FCP5-A was isolated from fruit of Cornus officinalis with water extraction and column chromatography. HPGPC shows that it was homogeneous polysaccharide with an average molecular weigh of 8.7×104. Monosaccharide analysis by GC shows that it was composed of rhamnose, arabinose, galactose and galacturonic acid with a molar ratio of 1∶ 5.7∶ 0.6∶ 1.2. By means of IR, GC, partial hydrolysis with acid, uronic acid reduction, methylation, GC-MS and 13C NMR analysis, the results indicate that FCP5-A was a branched polysaccharide rich in arabinose. The backbone was composed of 1,2-linked Rha and 1,4-linked GalA, with side chains attached to O-4 of the rhamnosyl residues. The side chains contained highly branched arabinan and short linear 1,3-linked galactan. It was concluded that FCP5-A was a new acidic branched polysaccharide of Cornus officinalis.