苦瓜多糖的提取、分离纯化及组成性质

正交实验确定提取工艺后,用热水提取法得到苦瓜多糖(MCP).对MCP进行DEAE-32离子交换层析分离,得到3个多糖组分MCP1、MCP2和MCP3. 进一步采用Sephacryl S-400凝胶层析进行分离,经凝胶层析和高效液相色谱检测表明,MCP1、MCP2为均一性多糖组分.通过高效液相凝胶色谱法测定了两者的相对分子质量分别为1.16×106和7.45×105.用PMP衍生化法测定其单糖,结果表明: MCP1系由Man、Rham、GlcUA、GalUA、Glu、Gal、Xyl、Ara等单糖组成的杂多糖,摩尔比为1.03:2.93:1.00:14.95:2.16:30.70:2.85:4.50.MCP2系由Rham、GalUA、Gal、Xyl、Ara等单糖组成的杂多糖,对应的摩尔比为1.63:21.88:4.66:1.00:1.29.紫外光谱表明该多糖不含蛋白质和核酸.

Extraction, isolation, purification and composition of Momordica charantia polysaccharide

Crude polysaccharides were extracted from Momordica charantia with hot water.Three main fractions of Momordica charantia polysaccharides（MCP）： MCP1,MCP2 and MCP3 were obtained through purification on DEAE-32 ion exchange column.The fractions were further isolated by Sephacryl S-400 gel-permeation chromatography.The results by Sephacryl S-400 and HPLC showed that MCP1 and MCP2 were both homogeneous.The molecular weight of MCP1 and MCP2 were 1.16×10 6 and 7.45×105,respectively measured by high performance gel permeation chromatography.The components of MCPs were determined by HPLC after PMP-derivatization.The results showed that MCP1 was heteropolysaccharides composed of Man,Rham,GlcUA,GalUA,Glu,Gal,Xyl and Ara,with respective molar ratios of 1.03∶2.93∶1.00∶14.95∶2.16∶30.70∶2.85∶4.50.MCP2 was composed of Rham,GalUA,Gal,Xyl and Ara,with respective molar ratios of 1.63∶21.88∶4.66∶1.00∶1.29.No typical absorption of nucleic acid or protein was detected by UV scanning.