紫心甘薯多糖的分离及组分抑癌活性研究

Anti-tumor activity of components isolated from purple sweet potato polysaccharides

目的:分离紫心甘薯的多糖(Polysaccharide of purple sweet potato,PPSP)组分,并对其组分的抑癌活性进行初步研究。方法:采用DEAE-Cellulose和CM-Cellulose离子交换柱分离紫心甘薯多糖,收集分离PPSP组分;MTT法检测PPSP各组分对肿瘤细胞的体外抑制活性;薄层层析法分析PPSP各组分的单糖组成;利用傅里叶红外光谱技术检测PPSP组分的结构特征。结果:选用弱阴离子交换柱DEAE-Cellulose分离,并经NaCl溶液梯度分段洗脱,得到4个紫心甘薯多糖组分,分别命名为PPSPⅠ、PPSPⅡ、PPSPⅢ和PPSPⅣ;观察PPSPⅠ、PPSPⅡ、PPSPⅢ对Hela和HepG2肿瘤细胞的抑制作用,检测发现PPSPⅡ、PPSPⅢ组分有一定的抑癌活性。结构分析结果表明,PPSPⅠ主要由葡萄糖和半乳糖这两种单糖组成;PPSPⅡ由葡萄糖组成,并具有β-D-葡萄吡喃聚糖的红外特征吸收峰;PPSPⅢ具有蛋白吸收峰。结论:成功分离得到PPSP的4种多糖组分,其中检测到PPSPⅡ、PPSPⅢ组分对Hela和HepG2肿瘤细胞具有一定的体外抑制作用。推测PPSPⅡ、PPSPⅢ组分抑癌活性可能与其含有β-D-葡萄吡喃聚糖或糖蛋白的结构有关。

Objective:To isolate and purify components from polysaccharides of purple sweet potato(PPSP) and to test their anti-tumor activity.Methods:DEAE-Cellulose and CM-Cellulose exchange chromatography were applied to separate components of PPSP.The anti-tumor activities of each component were measured by MTT assay on Hela and HepG2 cells and their monosaccharide composition were analyzed by TLC chromatography,followed by infrared spectroscopy studies.Results:Through weak anion exchange chromatography and gradient elution by sodium chloride solution,four components were separated and named as PPSP,PPSPⅡ,PPSPⅢ and PPSPⅣ,respectively.MTT tests showed that PPSPⅡ and PPSPⅢ inhibited Hela and HepG2 tumor cells in a certain extent.The structural analysis revealed that PPSPI was mainly composed of glucose and galactose,PPSPⅡwas composed of glucose and had a typical absorption peak of β-D-glucose chitosan pyranose,PPSPⅢ was a glycoprotein showing a protein absorption peak.Conclusion:Four components were separated from PPSP successfully,among which PPSPⅡ and PPSP Ⅲ shows anti-tumor activities on Hela and HepG2 cells in vitro.