裂壶藻(Schizochytrium limacinum)多糖的提取分离及其结构特性

Extraction,isolation and structural characterization of polysaccharides from Schizochytrium limacinum

目的从裂壶藻(Schizochytrium limacinum)中提取分离多糖并对其进行结构特性分析。方法采用热水提取并结合Q-Sepharose Fast Flow强阴离子交换柱分离,从中获得2种多糖组分(SLW1和SLW2)。运用高效液相色谱法(HPLC)、高效凝胶渗透色谱法(HPGPC)、傅里叶变换红外光谱(FTIR)、甲基化和核磁共振碳谱(13 C-NMR)法分别对其单糖组成、相对分子质量及结构特性进行了分析。结果 2种多糖均以Gal为主(>75%),且含有少量的Glc、Man和GlcN;相对分子质量分别为39.8kD和103.8kD;FTIR显示它们均属于硫酸多糖,其硫酸酯基主要位于半乳糖残基的C6位。结论结构分析表明:SLW2中含有→6)Galf(1→、→5)Galf(1→、→3,4)Galp(1→、→3)Galp(1→以及→4,6)Galp(1→等多种连接方式。

Objective To extract and purify polysaccharides from Schizochytrium limacinum and determine their structures.Methods Two polysaccharides（SLW1（2）were extracted with hot water and followed by Q-Sepharose Fast Flow strong anion exchange chromatographic purification.The monosaccharide composition,relative molecular mass and structural characters of the polysaccharides were studied by high performance liquid chromatography（HPLC）,high performance gel permeation chromatography（HPGPC）,Fourier transform infrared spectroscopy（FTIR）,methylation and 13C-NMR spectroscopy,separately.Results The two polysaccharides were mainly consisted of Gal（75 %）with a small amount of Man,GlcN and Glc.Their relative molecular masses were 39.8 kD and 103.8 kD separately.The FTIR data confirmed the existence of sulfate ester located at C6 hydroxyl groups of Gal.Conclusion The results of structural study demonstrated SLW2 contains linkages of →6）Galf（1→、→5）Galf（1→、→3,4）Galp（1→,→3）Galp（1→ and →4,6）Galp（1→.