枸杞多糖的纯化及相对分子质量研究

Study on purification technology and molecular weight of polysaccharides in Lycium Barbarum L.

旨在研究枸杞多糖(LBP)的纯化,并测定其相对分子质量。采用色谱法和溶剂法研究了LBP的脱色条件;利用HPLC法分别考查了醇沉、DEAE纤维素色谱柱和SephedexG-75葡聚糖凝胶色谱柱对LBP的纯化效果,并测定了多糖的相对分子质量。结果表明:最佳脱色条件为多糖溶液(0.2%,g/v)∶氯仿∶正丁醇=25∶5∶1(v/v/v)。5次醇沉可有效减少LBP中的小分子杂质;DEAE纤维素色谱柱可将枸杞多糖分为6个组分,其中以0.15mol/L和0.20mol/L的NaCl溶液为洗脱液获得的组分(LBP-4、LBP-5)含量较高;采用Sephedex G-75色谱柱对LBP-4和LBP-5进行纯化,分别得到LBP-4a和LBP-5a,经琼脂糖凝胶电泳及HPLC检验证明其为纯品,M珚n分别为866130D和1412100D。

Purification technology of polysaccharides from the Lycium Barbarum L.was studied.The molecular weights were determinate.The decoloration methods of chromatography and menstruum were compared.The purification effects of ethanol precipitation method,DEAE-cellulose chromatography and Sephadex G-25 chromatography on LBP were observed.The of LBP was determined by HPLC.The results showed that the best decoloration method was menstruum method with the conditions of：LBP（0.2%,g/v）,Chloroform：N-Butanol=25 ∶5 ∶1（v/v）.Precipitated with ethanol for 5 times,LBP was purified significantly.LBP was separated into 6 components by DEAE-cellulose column.The LBP-4 and LBP-5,eluted by 0.15mol/L and 0.20mol/L NaCl,are higher than other components.LBP-4 and LBP-5 was further purified by sephadex G-75 as LBP-4a and LBP-5a.The n of LBP-4a and LBP-5a were 866130D and 1412100D,respectively.