柘树根多糖的分离纯化及组成初步研究

以柘树（Cudrania tricuspidata （Carr.） Bur.）的根为材料，经热水抽提、木瓜蛋白酶-Sevag法除蛋白、乙醇沉淀和凝胶柱层析分离纯化，得到1种水溶性的柘树根多糖（CTP）并研究了其单糖组成. 采用紫外光谱和红外光谱法对柘树根多糖进行了定性分析，结果表明，柘树根多糖具有多糖特征性的紫外和红外吸收峰，不含糖醛酸；高效凝胶渗透色谱法测定结果表明，柘树根多糖的峰值分子量为18881；采用气相色谱法测定柘树根多糖中单糖的种类和构成比例，结果表明，柘树根多糖主要由葡萄糖、阿拉伯糖、半乳糖、木糖等4种单糖组成，并计算出4种单糖的摩尔组成比例.

Separation, purification and component research of a polysaccharide from the roots of Cudrania tricuspidata (Carr.) Bur.

A water-soluble polysaccharide (CTP) was obtained from the roots of Cudrania tricuspidata(Carr.) Bur., by water extraction (70℃), deproteination using the enzymolysis-Sevag method, precipitation with ethanol, and fractionation through DEAE-Sephadex A-50 and Sephadex G-75 chromatography. Monosaccharide composition, preliminary structure, and molecular weight of CTP were studied by ultraviolet (UV), infrared (IR), gas chromatography (GC), and high performance liquid chromatography (HPLC). CTP had characteristic UV absorption peaks, being identical with normal polysaccharides. High performance gel permeation chromatography (HPGPC) was used to determine the molecular weight of CTP, and the result showed that the average peak molecular weight of CTP amounted to 18881. Four monosaccharides, i.e. arabinose, xylose, galactose, and glucose were detected by gas chromatography from the CTP sample. The molar ratio of the four monosaccharides was measured.