泡菜发酵专用短乳杆菌的高密度培养

Investigation on High Cell Density Cultivation of Lactobacillus brevis Specific for Vegetable Fermentation

为了实现泡菜发酵专用短乳杆菌H3的高密度细胞培养,考察了培养基成分、培养条件、中和剂以及补料策略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25 g/L,酵母粉15 g/L,柠檬酸1.53 g/L,柠檬酸钠18.58 g/L,VB620 mg/L,Mg SO4·7H2O 0.58 g/L,Mn SO4·5H2O 0.25 g/L,Tween-80 1 g/L,在培养过程中使用20%柠檬酸钠调节培养液p H值6.8~6.3、培养温度30℃、装液量40 m L/250 m L三角瓶,适宜补料培养方式为培养10 h和20 h时各补加4%的碳氮源（碳氮比为5∶3）。培养结束时培养液中短乳杆菌活菌数可达1.27×1010CFU/m L,为未优化前的7.5倍,是目前已报道的最高活菌数水平,为实现泡菜发酵专用的短乳杆菌发酵剂的工业化生产奠定基础。

In order to achieve the high cell density culture of Lactobacillus brevis H3,the effects of medium formula,culture conditions,neutralizers and feed batch methods on viable cell counts have been investigated. Suitable medium formulation are：25 g/L glucose,15 g/L yeast,1.53 g/L citric acid,18.58 g/L sodium citrate,20 mg/L VB6,0.58 g/L Mg SO4·7H2O,0.25 g/L Mn SO4·5H2O,1 g/L Tween-80. Optimal culture conditions are temperature 30 ℃,cultural fluid amount 40 m L,p H 6.3~5.8,using 20% sodium citrate as neutralizer. Appropriate feeding culture method is 4% carbon and nitrogen sources（C/N ratio 5：3）,which was added after 10 and 20 h,respectively. When fermented at the optimal culture conditions,the number of the bacteria cells was up to 1.27 ×1010CFU/m L,which was 7.5 times as high as that when it was not optimized.