鸡腿菇子实体多糖分离纯化工艺及结构研究

Optimum Isolation and Structural Analysis of Polysaccharide from the Fruiting Bodies of Coprinus comatus

摘要:

以多糖得率为指标，用正交试验对鸡腿菇子实体多糖的提取纯化工艺进行优化。用离子色谱和凝胶渗透色谱对粗多糖进行分离纯化，利用化学和光谱学方法对均一多糖CC30w-1进行结构分析。结果表明鸡腿菇子实体多糖最佳提取工艺为：提取次数为3次，提取时间为 1.5h，提取温度为95℃，料液比为1∶12；最佳脱蛋白条件：样品-氯仿+正丁醇为3∶1(V/V)，氯仿-正丁醇为3∶1(V/V)，反应时间为20min，脱蛋白次数为7；结构分析的结果表明：CC30w-1分子量为1.94×10⁴ Da，糖组成为Fuc∶Gal = 1∶4.02；岩藻糖以端基方式连接，半乳糖主要以1,6-和1,2,6-两种方式连接,3个主要的连接方式的摩尔比为1.15∶2.88∶1；主要由(1,6)-α-D-Galp糖残基构成主链，在O-2位被α-Fucp糖残基取代的5个单糖残基组成的结构重复单元。

Abstract:

Optimum technique of isolation and purification of Coprinus comatus polysaccharides was investigated by orthogonal tests. DEAE-Sepharose F. F. and gel-filtration chromatography were used to separate and purify the Coprinus comatus polysaccharides, and get the homogeneous polysaccharide CC30w-1.The structure of CC30w-1 was studied with chemical and spectral methods. The results showed that the optimum conditions for the isolation was as follows： times of extraction 3, time 1.5h, temperature 95℃, material to water ratio 1∶12.The optimum deproteinization condition is that crude polysaccharide solute in the mixed solvent of chloroform and n-butanol (3∶1) whose volume 3 times that of the former, the reaction time and times of purification were 20 minutes and 7 times, respectively. CC30w-1 molecular weight was estimated to be 1.94×10⁴ by HPLC. HPAEC showed CC30w-1 was composed of fucose and galactose in molar ratios of 1∶4.02. Methylation analysis and NMR data showed that it possess a pentasaccharide repeating unit have a backbone of (1→6)-linked galactose residues, and is substituted at 2-position by fucose residue.