陈大卫 刘莎莎 黄玉军

摘要 [目的]从实验室保藏的乳酸菌中筛选出耐酸耐胆盐能力较强的乳酸菌，并研究其对肠上皮细胞的黏附能力及对肠道病原菌的抑制能力。[方法]通过模拟人工胃肠液及体外与IEC-6细胞共培养来分别研究乳酸菌的耐酸耐胆盐能力及对细胞的黏附能力，并利用单层琼脂平板扩散法测定其抑菌效果。[结果]试验的27株乳酸菌中，10株乳酸菌在pH 3.0的人工模拟胃液中培养3 h的存活率均大于44.00%，在pH 8.0的人工模拟肠液中培养4 h的存活率均大于51.56%，在含0.30%胆盐的培养基中培养24 h的存活率均大20.00%；其中菌株C13、A03、A17及A90对IEC-6细胞的黏附个数均大于8个/cell；菌株C13、A03对艰难梭菌、沙门氏菌和大肠杆菌的抑制能力较强，抑菌圈直径均大于22 mm。经16S rRNA测序将C13 和A03分别鉴定为鼠李糖乳杆菌（Lactobacillus rhamnosu）和植物乳杆菌（Lactobacillus plantarum）。[结论] L.rhamnosu C13、L.plantarum A03的耐酸耐胆盐能力及对上皮细胞的黏附能力较强，对肠道病原菌有较好的抑制作用，可作为良好的抑制肠道病原菌的候选益生菌株。

关键词 乳酸菌；耐酸耐胆盐；黏附；抑菌

中图分类号 TS252.1 文献标识码 A 文章编号 0517-6611（2017）34-0078-03

Abstract [Objective] Lactic acid bacteria （LAB） with strong resistance of acid and bile salt were screened from laboratory，and their adhesion ability of intestinal epithelial cells and inhibition ability to intestinal pathogens were studied.[Method]The resistance of acid and bile salt and the adhesion ability of IEC6 cells were studied by artificial gastrointestinal fluid and cocultured with IEC6 cells，respectively，and the bacteriostatic effect was deter mined by single agar plate diffusion method.[Result]The survival rate of 10 strains were cultured 3 h in pH 3.0 artificial gastric juice was greater than 44.00%，and cultured 4h in pH 8.0 artificial intestinal juice was greater than 51.56%，and cultured 24 h in medium containing 0.30% bile salts was greater than 20.00%； the adhesion number of C13，A03，A17 and A90 on IEC6 cells was greater than 8 cells； the inhibiting capacity of C13，A03 on Clostridium difficile，Salmonella and Escherichia coli was stronger than others，the antibacterial circle diameter was greater than 22 mm.C13 and A03 were identified as Lactobacillus rhamnosu and Lactobacillus plantarum by 16S rRNA sequencing，respectively.[Conclusion]L.rhamnosu C13，L.plantarum A03 with the strong ability of acid and bile salt resistance and adhesion to epithelial cells，which have good inhibitory effect on pathogenic bacteria，and can be used as a fit probiotic candidate strain.

Key words Lactic acid bacteria； Resistance of acid and bile salt； Adhesion； Inhibition of pathogenic bacteria

腸道菌群在维持机体的健康过程中发挥着重要的作用，与人体的消化营养、免疫代谢、生物拮抗等密切相关[1]。抗生素由于见效快、针对性强等特点被大量用于疾病的治疗，而其过度使用导致了肠道菌群的紊乱，引起了艰难梭菌、沙门氏菌、大肠杆菌等肠道致病菌的繁殖，进而引发机体腹泻、呕吐、酸中毒等症状，同时也会导致机体易感染情况增加，引起二重感染，降低其免疫功能，对机体的健康产生了严重的影响[2-3]。……