混合乳酸菌对小鼠肠上皮细胞的粘附及抑菌机制

目的 研究混合乳酸菌粘附及抑菌机制。方法 测定混合菌株粘附相关能力及抑菌方式，初步研究菌株粘附相关的表面活性成分。结果 混合菌株的表面疏水性、自聚合能力较高，对ICE-6细胞的粘附性亦较高。可抑制G+菌（金黄色葡萄球菌、枯草杆菌、艰难梭菌）和G‒菌（大肠埃希菌、沙门菌、假单胞菌）粘附ICE-6细胞，抑制方式效果为排除>竞争>替代；热处理对菌株粘附性影响明显高于胃蛋白酶、胰蛋白酶、LiCl和NaIO4等处理，表面蛋白（80~140 kDa）可使LiCl处理菌株的粘附率提升45%。结论 混合乳酸菌主要通过排除方式抑制外源菌的粘附，表面蛋白影响混合乳酸菌的粘附能力。

The mechanism of the adhesion and inhibition of mixed Lactic acid bacteria to the intestinal epithelial cells of rats

Abstract: Objective To study the mechanism of the adhesion-inhibition of mixed Lactic acid bacteria. Methods The adhesion related activity and bacteriostatic way of the mixed strains were detected. The surface active components related to the adhesion was preliminarily researched. Results The mixed strains possessed certain hydrophobicity, aggregation activity and high adhesive activity to the ICE-6 cells. Meanwhile, the adhesion of three Gram-positive bacteria (Staphylococcus aureus, Bacillus subtilis, Clostridium difficile) and three Gram-negative bacteria (Escherichia coli, Salmonella WX29, Pseudomonas brenneri) to the ICE-6 cells were inhibited by the mixed strains. The most effective way of the inhibition was exclusion, followed by competition and replacement. Moreover, thermal treatment affected the adhesion activity of the mixed strains more significantly than pepsin, trypsin, LiCl and NaIO4 did. Surface protein (80 - 140 kDa) was extracted and incubated with the treated mixed strains and the adhesion rate was improved by 45%. Conclusion The mixed Lactic acid bacteria mainly used the exclusion mechanism to inhibit the adhesion of extracellular bacteria to to the cells. Surface protein played important roles in the adhesion-inhibition activity of the mixed Lactic acid bacteria.