杜仲叶多糖的提取分离、抗补体活性及结构研究

Isolation,Anti-complement Activities,and Chemical Structures of Polysaccharide from Eucommia ulmoides Leaves

经石油醚脱脂、除胶后,采用热水提取、分步醇沉工艺获得杜仲叶水溶性多糖PsEUL1、PsEUL2、PsEUL3,分别经S-8大孔树脂脱色,Sevag法脱蛋白及透析,其中PsEUL1经DEAE-52纤维素柱层析分离得多糖组分PsEUL11、PsEUL12、PsEUL13,抗补体活性实验表明,其中有多个组分有不同程度的抗补体活性,并呈一定的剂量效应关系。活性多糖PsEUL13经硫酸-咔唑反应及气相色谱法测定,单糖组成为:L-鼠李糖、D-岩藻糖、D-阿拉伯糖、D-木糖、D-葡糖糖、D-半乳糖、糖醛酸,含量比为11.8∶1.6∶37.7∶4.2∶10.7∶12.8∶21.2。

After removal of resin and gutta percha under petroleum ether reflux,Eucommia ulmoides Leaves were decocted with distilled water and the extract was concentrated and fractionally precipitated by adding the one-fold,two-fold and three-fold volumes of alcohol to obtain three groups of crude polysaccharides,PsEUL1,PsEUL2,and PsEUL3.Of them,the group of polysaccharides,PsEUL1,was decolourized on a macro-porous resin（S-8） column and deproteinized using Sevag reagent.After dialysis,the refined PsEUL3 was applied to a diethylaminoethyl（DEAE）-cellulose anion exchange column and isolated into three monomeric polysaccharides,PsEUL11,PsEUL12,and PsEUL13.The assays of anti-complement activities indicated many fractions of polysaccharides have different extent of inhibitory activities with dose-effect relationships.PsEUL13 was demonstrated to be an acidic polysaccharide by reacting with sulfuric acid and carbazole,containing 21.2% of uronic acid.The gas chromatography revealed that it was composed of L-rhamnose,D-fucose,D-arabinose,D-xylose,D-glucose and D-galactose besides uronic acid,their percentage composition being 11.8,1.6,37.7,4.2,10.7 and 12.8,respectively.