藏灵菇源干酪乳杆菌KL1胞外多糖抑制人结肠癌细胞增殖的研究  

Inhibitory Effect of Exopolysaccharides Produced by Lactobacillus casei Strain KL1 from Tibetan Kefir on Proliferation of Human Colon Cancer Cells

作　　者：邢书涵[1] 连正兴[2] 孙勇 韩红兵[2] 钟思琼[4] 刘慧[1] 

机构地区：[1]北京农学院食品科学与工程学院,北京102206 [2]中国农业大学动物科技学院,农业生物技术国家重点实验室,北京100094 [3]北京市食品研究所,北京100162 [4]华中农业大学食品科学技术学院,湖北武汉430070

出　　处：《食品科学》2012年第7期284-288,共5页Food Science

基　　金：北京市自然科学基金项目(5092008;5062006);北京市重点建设学科资助项目(PXM2009_014207_078172)

摘　　要：分离纯化藏灵菇源干酪乳杆菌KL1胞外多糖(EPS),研究EPS纯品对HCT-8人结肠癌细胞的增殖抑制和诱导细胞凋亡作用。利用Sepharose CL-6B凝胶柱探讨干酪乳杆菌KL1菌株EPS粗品的纯化条件,应用紫外全波长扫描及苯酚-硫酸法鉴定EPS纯度;采用CCK-8法和Annexin V-FITC细胞凋亡检测试剂盒研究EPS对HCT-8人结肠癌细胞的增殖抑制和凋亡作用。结果表明:在0.02～0.12mol/L磷酸盐缓冲液梯度洗脱、流速3mL/min、样品上样质量浓度15.0mg/mL、样品上样量2.0mL的纯化条件下获得EPSa和EPSb两个单一组分的胞外多糖,其纯度分别为91.67%和82.86%。EPSa处理HCT-8人结肠癌细胞体外实验发现,EPSa对HCT-8细胞的增殖有抑制作用,以及诱导细胞凋亡的发生,且细胞生长抑制率呈时间-剂量依赖性。提示藏灵菇源干酪乳杆菌KL1菌株的EPSa有抑制结肠癌细胞增殖的生物活性。In this study, exopolysaccharides （EPS） produced by Lactobacillus casei strain KL1, isolated from Tibetan Kefir, were purified and used to explore the effect on the proliferation of human colon cancer HCT-8 cells. The EPS was purified by Sepharose CL-6B gel column and its purity was evaluated by UV scanning spectroscopy and phenol-sulfuric acid assay. The cell proliferation and apoptotic effect of EPS on HCT-8 cells was examined by CCK-8 assay and Annexin V-FITC apoptosis detection kit. Two individual components （EPSa and EPSb） were obtained under the optimal purification conditions： gradient elution with 0.02-0.12 mol/L phosphate buffer at a flow rate of 3 mIdmin, and sample concentration of 15.0 mg/mL with a loading volume of 2.0 mL. The purities of EPSa and EPSb were 91.67% and 82.86%, respectively. EPSa could inhibit HCT-8 cell proliferation and induce cell apoptosis. The inhibitory rate of cell growth was in a dose-dependent manner. Therefore, EPSa reveals therapeutic effect on colon cancer.

关 键 词：干酪乳杆菌 胞外多糖 HCT-8人结肠癌细胞 抑制增殖 细胞凋亡 

分 类 号：TS210.1[轻工技术与工程—粮食、油脂及植物蛋白工程]