双歧杆菌的粘附特性及其对肠道致病菌的体外拮抗作用

In vitro Adherence Properties of Bifidobacterium Strains and Their Antagonistic Activity Against Enteropathogens

摘要:

本文采用体外细胞培养法, 从实验室现有的20株不同生境来源的双歧杆菌中筛选具有较强粘附能力的菌株, 并通过混合培养和牛津杯方法, 研究了具有粘附特性的双歧杆菌对肠道致病菌的体外拮抗作用。结果显示, 长寿老人源菌株A03和I06的粘附能力最强, 其菌液对金黄色葡萄球菌及大肠杆菌均具有显著的抑制性, 但是菌体及中和后的发酵液均没有抑菌性, 说明受试菌主要通过其代谢产物中的有机酸来发挥其抑菌性能; 此外, 通过分析比较受试菌和肠道致病菌分别与Caco-2细胞粘附后释放的乳酸脱氢酶量, 证实双歧杆菌与致病菌对细胞的作用具有本质上的区别, 双歧杆菌的粘附能减缓致病菌对细胞所造成的损害。

Abstract:

Twenty bifidobacterial strains were tested for adherence ability with cellular model systems in vitro. Strain A03 and I06 showed high adherence to the epithelial cells. The inhibitory effects of Strain A03 and I06 on enteropathogen Staphylococcus aureus and Escherichia coli were demonstrated by simultaneous incubation and antimicrobial testing. These antibacterial activities were mainly induced by organic acids produced by bifidobacteria. The release of LDH of Caco-2 cells which were differently treated with bifidobacteria and enteropathogen, suggested that the adherence of bifidobacteria were essentially different with those of enteropathogen, and the adhesion of strain A03 and I06 could prevent the harmful effect of S. aureus and E. coli on Caco-2 cells.