茶多糖的分级纯化及组成分析

Purification of Tea Polysaccharide and its Physicochemical Characteristics

从粗老绿茶中提取茶叶粗多糖,经DEAE-纤维素DE-52和SephacrylS-300柱层析纯化,获得三个纯化的茶多糖组分:TPS2-H2O、TPS2-0.25和TPS2-0.40;此三个组分的中性糖含量分别是:41.23%、29.33%和21.39%,糖醛酸含量分别是:19.5%、22.5%和56.4%,蛋白质含量分别是:未检出、0.8%和未检出;GC-MS分析了三个分级组分均由鼠李糖、阿拉伯糖、木糖、甘露糖、葡萄糖和半乳糖等六种单糖构成的杂多糖,其摩尔比分别是TPS2-H2O(21.3:13.8:1.8:23.3:6.9:32.9),TPS2-0.25(60.7:13.4:1.6:2.0:1.2:21.1),TPS2-0.40(60.2:10.8:4.4:3.2:5.7:15.7);HPGPC-ELSD法分析了各组分的分布及所占比重。

CTPS（Crude tea polysaccharide, CTPS） were extracted from coarse tea, CTPS were purified by DEAE-cellulose and Sephacryl S-300 column chromatography, there fractions of TPS were obtained, TPS2-H2O, TPS2-0.25 and TPS2-0.40. The contents of neutral saccharide of them were 41.23%, 29.33% and 21.39% respectively, and the contents of uronic acid, 19.5%, 22.5% and 56.4%, and the contents of protein, not detected, 0.8% and not detected. By means of GC, the monosaccharide composition and its molar ratio of the polysaccharides were confirmed, and they are rhamnose, arabinose, xylose, mannose, glucose and galatose. Relative molecular mass and its mass ratio were determined using high performance gel permeation chromatography （HPGPC） with the ELSD detector.