薯蓣多糖的分离、纯化、组成及其某些性质

中药薯蓣(Dioscorea Opposita)块茎经冷水,热水分别浸提的产物,通过脱蛋白,丙酮分级沉淀,高速离心和凝胶柱层析得到一系列性质各异的多糖。纸层析、气相色谱的结果表明热提物多糖主要由葡萄糖组成,而冷提物多糖由甘露糖组成。kunz法测得冷提物级分PF-Ⅲ和PF-Ⅳ分别含有15.6％和8.3％的乙酰基团。红外光谱显示热提物级分为α构型,而冷提物多糖为β构型。

Isolation, Purification, and some properfies of polysaccharides from Dioscorea Opposita Thunb

Extration of tubers of Dioscorea Opposita Thunb with cold water yield a mixture of polysaccharides containing mannan associated firmly with protein.The mixture was separated bydeprotein, high speed centrification, and gel filtration using a Sephadex G-75 column to obtain a series of polysaccharides, in which PF-3 and PF-4 contained 15.6％ and 8.3％acetyl groups separately by IR spectrum and chemical methods.M.W of PF-3 and PF-4 are 2x10~4 and 1.7x10~4 separately.IR indicated they have β-configuration. The residue of the cold water extract of the tubers was treated with hot water, yielding starch-like polysaccharides. They are separated by fractional precipitation with acetone, their M.W have determinated. IR indicated that they havea—configuraton.