Abstract: Lactobacillus acidophilus LA-G80, isolated from the human intestinal flora, has probiotic functions. In this study, the medium composition and culture conditions for this strain were optimized. The results obtained showed that the optimal medium consisted of glucose 41.5 g/L, maltose 20 g/L, soybean oligosaccharide 10 g/L, beef extract powder 18.64 g/L, tryptone 10 g/L, yeast peptone 15 g/L, Tween-80 1 mL/L, K2HPO4·7H2O 2 g/L, NaAc·3H2O 5 g/L, triammonium citrate 2 g/L, MgSO4·7H2O 0.25 g/L, MnSO4·4H2O 0.05 g/L, aspartic acid 0.16 g/L, alanine 0.16 g/L, serine 0.16 g/L, peanut protein powder 5 425 g/L, and soybean cake powder 7 425.48 g/L. The optimal culture conditions were as follows: inoculum size 2%, initial pH 6.0, constant pH 5.5, and constant temperature 37 ℃. Experiments carried out in a 5 L fermenter gave a viable cell count of 42.2 × 108 CFU/mL, which was about 10 times higher than that of observed with MRS medium.

Key words: Lactobacillus acidophilus LA-G80; fermentation medium; optimization; culture substrates

摘要： 嗜酸乳杆菌LA-G80分离自人体肠道菌群，具有益生功能。通过发酵培养基及培养条件优化，获得较 优的培养基配方和培养条件。结果表明：嗜酸乳杆菌LA-G80的最佳发酵培养基组成为葡萄糖添加量41.5 g/L、 麦芽糖20 g/L、大豆低聚糖10 g/L、牛肉浸粉18.64 g/L、胰蛋白胨10 g/L、酵母蛋白胨15 g/L、吐温-80 1 mL/L、 K2HPO4·7H2O 2 g/L、NaAc·3H2O 5 g/L、柠檬酸三铵2 g/L、MgSO4·7H2O 0.25 g/L、MnSO4·4H2O 0.05 g/L、 天冬氨酸0.16 g/L、丙氨酸0.16 g/L、丝氨酸0.16 g/L、花生蛋白粉5 425 g/L、豆饼粉7 425.48 g/L；最佳培养条件为 接种量2%、初始pH 6.0、恒定pH 5.5、恒温37 ℃；利用5 L发酵罐进行验证实验，采用优化后培养基及培养条件培 养，嗜酸乳杆菌LA-G80的活菌数达42.2×108 CFU/mL，相较MRS基础培养基提高约9 倍。

关键词: 嗜酸乳杆菌LA-G80；发酵培养基；优化；粗料