蛹虫草多糖的分离纯化及促胆固醇逆向转运研究

Separation,purification and primary reverse cholesterol transport study of Cordyceps militaris polysaccharide

对蛹虫草子实体多糖进行分离纯化、相对分子质量测定、单糖组成分析和体内胆固醇逆向转运活性研究。采用阴离子交换色谱、分子排阻色谱分离纯化多糖,高效凝胶渗透色谱法测定相对分子质量,高效液相色谱结合柱前衍生法测定单糖组成,同位素示踪技术评价胆固醇转运活性。最终获得3种纯多糖组分CMBW1,CMBW2和CMYW1,糖含量依次为87%,89%,95%,蛋白含量依次为6.5%,1.3%,2.8%,相对分子质量依次为772.1,20.9,13.2 kDa;CMBW1由Man,GlcN,Rha,GlcUA,Glc,Gal和Ara构成,摩尔比例为7.25:0.17:1.29:0.23:6.30:11.08:0.79;CMBW2由Man,GlcN,Gal和Ara组成,摩尔比例为2.40:0.16:2.92:0.24;CMYW1由Man,GlcN,GlcUA和Glc组成,摩尔比例为0.59:0.57:0.45:25.61;蛹虫草多糖50 mg·kg^(-1)即可显著促进~3H-胆固醇向小鼠血液转运和经由粪便排出。所得3种蛹虫草多糖组分均为杂多糖,所得蛹虫草多糖具有促胆固醇逆向转运功能。

The authors designed to separate, purify and determine the monosaccharide composition of the polysaccharide from Cordyceps militaris, and study its effect on reverse cholesterol transport in vivo by isotope tracing assay. Polysaccharides were separate and purify by ion exchange column Q-sepharoseTM Fast Flow and size exclusion column Sephacryl S200HR; the molecular weight and monosaccharide composition of the polysaccharides were determined by high performance gel permeation chromatography and high performance liquid chromatography coming with pre-column derivation, respectively. Finally, three purified polysaccharides CMBW1, CMBW2 and CMYW1 were obtained, their total carbohydrate contents were 87%, 89%, 95%, respectively; their protein contents were 6. 5%, 1.3% , 2. 8%, respectively; their molecular weights were 772. 1, 20. 9 , 13.2 kDa, respectively; CMBW1 was composed of mannose, glucosamine, rhamnose, glucuronic acid, glucose, galactose and arabinose with a molar ratio of 7. 25：0. 17： 1.29： O. 23： 6. 30：11.08： 0.79; CMBW2 was composed of mannose, glucosamine, galactose and arabinose with a molar ratio of 2. 40： 0. 16： 2. 92： 0. 24; CMYW1 was composed of mannose, glucosamine, glucuronic acid and glucose with a molar ratio of 0. 59：0. 57： 0. 45： 25.61. Polysaccharide at 50 mg · kg^-1 could significantly improve the transport of ^1H- cholesterol to blood and excretion from feces. All of the three purified polysaccharides CMBW1, CMBW2 and CMYW1 were heteropolysaccharide; and they could improve reverse cholesterol transport in vivo, the underlying mechanisms are being studied.