蔬菜发酵专用乳酸菌的菌体高密度培养

Investigation on Dense Cultivation of Lactobacillus Specific for Vegetable Fermentation

菌体高密度培养是制备浓缩型蔬菜发酵专用菌粉的关键。采用缓冲盐法、化学中和法和补料培养法进行乳酸菌NCU0101的菌体高密度培养,分析研究培养基配方、培养条件、补料培养方式对菌体活菌数的影响。结果表明:菌体适宜培养基配方为葡萄糖5%、蛋白胨1%、磷酸氢二钾0.5%、醋酸钠0.3%,适宜培养条件为培养液pH值6.3～5.8、培养温度30℃、振荡频率40r/min、培养时间20h,适宜补料培养方式为培养0、4和8h时各补加2.5%的碳氮源(碳氮比为5:1);培养结束后,培养液中乳酸菌菌体活菌数可达7.83×109CFU/ml。

Dense cultivation is the key to prepare concentrated bacterial powder for vegetable fermentation. The study of high cell density culture of lactobacillus No. NCU 0101 has shown that it is feasible to achieve the goal using buffer solution, chemical neutralization and feed batch culture. It is found that medium formula, culture conditions, and feed batch methods have great impacts on biomass growth. Suitable medium formulation is： 5% glucose, 1% peptone, 0.5% K2HPO4, 0.3% sodium acetate. Optimal culture conditions are pH 6.3-5.8, temperature 30 ℃, oscillation frequency 40 r/min, and culture time 20 h. Appropriate feeding culture method is that 2.5% carbon and nitrogen sources （C/N ratio is 5：1） is added respectively after 0, 4 and 8 h. With the optimal culture conditions, the number of the bacteria cells is up to 7.83×10^9CFU/ml.