香菇子实体蛋白多糖的分离纯化及组成结构分析

Isolation, purification and characterization of polysaccharides from the fruitbody of Lentinus edodes (Berk.) Sing.

香菇〔Lentinusedodes (Berk .)Sing .〕子实体经热水提取 ,乙醇沉淀 ,得多糖粗品 (Le)。Le脱游离蛋白 ,脱色 ,经DEAE 纤维素柱及纤维素凝胶柱层析分离纯化得到Le 1、Le 2和Le 3 3个级分。经聚丙烯酰胺凝胶电泳和SepharoseCL 6B柱层析鉴定为分子量分布均一的蛋白多糖。凝胶渗透色谱法测得Le 1、Le 2和Le 3分子量分别为 95 40 0 0 ,90 0 0 0和 140 0 0。3个级分均由阿拉伯糖、木糖、甘露糖、半乳糖、葡萄糖和葡萄糖醛酸组成 ,气相色谱测得Le 1的阿拉伯糖、木糖、甘露糖、半乳糖、葡萄糖的摩尔比为 0 .39∶0 .46∶1.0 0∶0 .93∶14.13;Le 2为 0 .19∶0 .41∶1.0 0∶0 .93∶10 .72 ;Le 3为 0 .31∶0 .47∶1.0 0∶1.15∶8.92。Le 1、Le 2和Le 3葡萄糖醛酸含量 (% )分别为 2 4.10、34.77和 40 .0 5 ,蛋白质含量 (% )分别为 2 .0 1、7.38和 2 5 .31,红外扫描确定Le 1和Le 2的糖苷键为α型 ,Le 3为

After being extracted with hot water and precipitated with alcohol, crude polysaccharide (Le) was obtained from fruitbody of \%Lentinus edodes \%(Berk.) Sing. Le was removed free proteins and colouring matter, then isolated and purified by DEAE\|cellulose and cellulose gel column chromatography, three pure polysaccharides (Le\|1, Le\|2, Le\|3) were obtained. Results of polyacrylamide gel electrophoresis and Sepharose CL\|6B column chromatography illustrate that they were protein\|bond polysaccharides with homogeneous molecular weights.\ Molecular weights of Le\|1,\ Le\|2 and Le\|3 were 954 000,\ 90 000 and 14 000, respectively, by gel permeation chromatography. Three fractions were composed of arabinose (Ara), xylose (Xyl), mannose (Man), galactose (Gal), glucose (Glc) and glucuronic acid. Gas chromatography illustrated that the neutral saccharides molar ratio of Le\|1 was Ara∶Xyl∶Man∶Gal∶Glc = 0.39∶0.46∶1.00∶ 0.93∶14.13; Le\|2 was Ara∶Xyl∶Man∶Gal∶Glc=0.19∶0.41∶1.00∶0.93∶10.72 and Le\|3 was Ara∶Xyl∶Man∶Gal∶Glc = 0.31∶0.47 ∶1.00 ∶1.15 ∶8.92. Glucuronic acid contents (%) of three fractions were 24.10, 34.77 and 40.05 and protein contents (%) were 2.01, 7.38 and 25.31, respectively. Infra\|red spectrum showed that the glycosidic linkages of Le\|1 and Le\|2 were α type, while that of Le\|3 was β type.