植物乳杆菌CGMCC.5297产细菌素条件的优化及应用

Optimization and applications of fermentation conditions for bacteriocin production by Lactobacillus plantarum CGMCC.5297

用响应面法对植物乳杆菌CGMCC.5297生产细菌素的培养基进行了优化。通过Plackett-Burman设计和中心组合试验设计,植物乳杆菌CGMCC.5297代谢产细菌素的最佳培养条件为酵母粉5.09g/L,牛肉膏10.85g/L,葡萄糖55.34g/L。此时的细菌素上清与指示菌单核细胞增多性李斯特菌CVCC1595共培养4h后,指示菌OD600nm为0.001 73,效价为4499 IU/mL,提高了1.4倍。在最优发酵条件下获得的试验结果与模型预测值吻合,说明所建立的模型是切实可行的。将优化后的植物乳杆菌上清加入到自制酸奶中,发现此细菌素对酸奶具有良好的保鲜效果。

In this study, the growth medium composition for bacteriocin-producing Lactobacillus plantarum CGMCC.5297 was optimized by response surface methodology. Based on the combined Plackett-Burman and central composite design, the optimal fermentation medium formula was determined： yeast extract powder 5.09 g/L, beef extract 10.85 g/L, glucose 55.34 g/L. Under the optimal culture conditions, the antibacterial activity of L.plantarum CGMCC.5297 increased by 1.4 times with the maximum of 4499 IU/ml and the OD600nmof indicator bacteria Listeria monocytogenes was0.001 73 after co-culturing of bacteriocin supernatant and L. monocytogenes CVCC1595 for 4 h. The results were in consistent with the theoretical predictions, implying that the optimization model was reasonable. The optimized L. plantarum supernatant was added in the home-made yoghourt and exhibited good preservation for the yoghourt.