益生菌大肠杆菌Nissle 1917抗逆性能、猪肠上皮细胞黏附率及抑菌效果研究

本试验旨在研究益生菌大肠杆菌Nissle 1917(Ec N)抗逆性能、猪肠上皮细胞黏附率及抑菌效果。采用体外法对Ec N进行生长曲线绘制和耐酸、耐胆盐、耐热性能的测定;以猪肠上皮细胞IPEC-J2细胞为体外细胞模型,考察了Ec N对该细胞的黏附率以及对致病菌大肠杆菌K88的黏附抑制率;同时通过蛋白质印迹法检测了Ec N对IPEC-J2细胞β-防御素-2和Toll样受体4的水平的影响。结果表明:1)Ec N对高酸、高胆盐和高温环境具有一定耐受能力。2)Ec N对IPEC-J2细胞的黏附作用以对数期最佳,黏附率达33.96%,显著高于迟缓期、稳定期和衰亡期(P0.05)。3)Ec N对致病菌大肠杆菌K88具有良好的抑制效果,黏附抑制率达87.84%。4)Ec N还能上调IPEC-J2细胞β-防御素-2和Toll样受体4水平。结果提示,益生菌Ec N具有较好的抗逆性能,能够良好地黏附猪肠上皮细胞,对致病菌大肠杆菌K88具有良好的抑制作用。

Probiotics Escherichia coli Nissle 1917: Stress Resistance,Swine Intestinal Epithelial Cell Adhesion Rate and Antimicrobial Effects

This experiment was conducted to investigate stress resistance, swine intestinal epithelial cell adhesion rate and antimicrobial effects of probiotics Escherichia coli Nissle 1917 ( EcN) . The growth curve, acid, bile salt and heat tolerance were analyzed using in vitro methods;IPEC-J2 cells of swine intestinal epithelial cells were se-lected as the in vitro cell model to investigate the effects of EcN on adhesion rate and inhibition rate of adhesion to an pathogenic bacterium Escherichia coli K88;meanwhile, the effects of EcN on levels of β-defensin-2 and toll-like receptor 4 of IPEC-J2 cells were identified by Western blot. The results showed as follows:1) EcN could sur-vive in strong acid, high concentration of bile salt and high temperature. 2) EcN in logarithmic phase had the high-est intestinal epithelial cell adhesion effect and its adhesion rate was 33.96%, which was significantly higher than that in retardation phase, stationary phase and decline phase ( P<0.05) . 3) EcN had good inhibitory effect on path-ogenic bacterium Escherichia coli K88 and its inhibition rate of adhesion was 87.84%. 4) EcN could up-regulate the levels ofβ-defensins-2 and toll-ike receptor 4. In conclusion, the probiotics EcN presents stress resistance, has great swine intestinal epithelial cells adhesion capacity, and prevents attack from pathogenic bacteria Escherichia coli K88.