淡红侧耳子实体多糖的分离纯化及结构探析

Purification and structure analysis of polysaccharides from Pleurotus djamor

以淡红侧耳子实体为原料,采用水提醇沉法进行提取,大孔阴离子交换树脂D315脱色,Sevage法脱蛋白,得到淡红侧耳子实体粗多糖;利用DEAE-纤维素-52和Sephadex G-150对粗多糖进行纯化;采用高效凝胶过滤色谱法和柱前衍生高效液相色谱法进行分子质量测定和单糖组成分析;通过紫外光谱扫描、红外光谱扫描及刚果红实验对其结构进行初步测定;并对其理化性质进行研究。结果表明,经纯化后得到3种组分PDP-1-1、PDP-2-1和PDP-3-1;相对分子质量分别为12. 9、10. 6和2 753. 7 k Da; PDP-1-1由甘露糖、葡萄糖、半乳糖、阿拉伯糖和岩藻糖5种单糖组成,PDP-2-1由甘露糖、葡萄糖、半乳糖、木糖、阿拉伯糖和岩藻糖6种单糖组成,PDP-3-1由甘露糖、葡萄糖、半乳糖和岩藻糖4种单糖组成;紫外扫描三组分均不含蛋白质和核酸,红外扫描均显示具有多糖特征吸收峰; PDP-1-1和PDP-3-1具有三股螺旋结构。

Polysaccharides were obtained from Pleurotus djamor by hot water extraction and alcohol precipitation.After removal of pigments and proteins by macroporous anion exchange resin D315 and Sevage method respectively,polysaccharides were purified by DEAE-cellulose-52 and Sephadex G-150. Molecular weight distribution and monosaccharide composition were analyzed by high performance gel filtration chromatography( HPGFC) and pre-column high performance liquid chromatography. The structures were preliminarily analyzed by ultraviolet,infrared spectrum and Congo red experiments. Their physicochemical properties were further determined. The results showed that three components were obtained with the molecular weights 12. 9,10. 6,2753. 7 k Da respectively. PDP-1-1 was composed of mannose,glucose,galactose,Arabia sugar and fucose; PDP-2-1 was composed of mannose,glucose,galactose,xylose,Arabia sugar and fucose; PDP-3-1 was composed of mannose,glucose,galactose and fucose. Ultraviolet spectrum confirmed that the fractions were free of protein and nucleic acid and the infrared spectrum showed the characteristic absorption peak of polysaccharides. PDP-1-1 and PDP-3-1 had triple-helical structure.