摘要
以分离自西班牙传统色拉米香肠的产细菌素弯曲乳杆菌(Lactobacillus curvatus)RX-6为研究对象,以单核细胞增生李斯特菌为细菌素抑菌活性测试指示菌,以相对抑菌效价为考察指标,对菌株RX-6代谢产细菌素的发酵培养基组成进行了优化。首先考察了不同碳源、氮源、刺激因子及磷酸盐缓冲液等单因素对细菌素合成的影响,确定碳源、氮源及刺激因子3个因素对细菌素的产量影响较为显著,而且最佳碳源为ɑ-乳糖,最佳氮源为1:1复配大豆蛋白胨和牛肉膏,最佳刺激因子为吐温80,因此选取这3因素继续进行响应面试验优化。优化结果显示,在培养温度为37℃、培养起始pH为6.5条件下,细菌素发酵的最佳培养基配方为:ɑ-乳糖2%、大豆蛋白胨0.6%、牛肉膏0.6%、K2HPO40.2%、乙酸钠0.5%、柠檬酸三铵0.2%、MgSO40.0058%、MnSO40.025%、吐温800.1%、蒸馏水1L。在此优化条件下,细菌素效价高达2386.69AU/mL,是优化前(970.42AU/mL)的2.46倍。同时,最优发酵条件下获得的试验结果与模型预测值相吻合,说明所建立的回归模型是切实可行的。
The fermentation medium composition of Lactobacillus curvatus RX-6 isolated from Spanish traditional Salami sausages, were optimized for bacteriocin production. The bacteriocin inhibitory activity （AU/mL） was used as evaluation index and quantified against L. monocytogenes ATCC 35152. Firstly, the effects of the single factors （carbon source, nitrogen source, PBS buffer and stimulating factor） onbacteriocin production from strain RX-6 were examined. Results showed the best carbon source was a-Lactose, the best nitrogen source was the 1：1 complex with soybean peptone and beef extract, and the best stimulating factor was Tween 80. Based on these single factor tests, response surface methology with three variables of carbon source, nitrogen source and stimulating factor was employed to optimize the fermentation medium composition for bacteriocin production. Results showed the optimal medium composition were： a-Lactose 2%, soybean peptone 0.6%, beef extract 0.6%, K2HPO40.2%, NaAc 0.5%, tri-ammonium citrate 0.2%, MgSO4 0.058%, MnSO4 0.025%, Tween 80 0.1%, H20 1000 mL. Under these optimal conditions, the bacteriocin inhibitory activity was increased by 2.46 times and reached up to 2386.69 AU/mL. Finally, the consistent results between the prediction and experiments indicated the established model in this study is feasible.
出处
《食品科技》
CAS
北大核心
2013年第3期2-8,共7页
Food Science and Technology
基金
国家自然科学基金项目(31201407)
关键词
响应面
细菌素
弯曲乳杆菌
发酵培养基组成
response surface methodology
bacteriocin
Lactobacillus curvatus
fermentation medium composition
