植物乳杆菌P158产细菌素培养基及培养条件的优化

为提高乳酸菌细菌素产量,以藤黄微球菌、铜绿假单胞杆菌为指示菌,通过单因素和正交试验优化植物乳杆菌P158产细菌素的培养基和培养条件。结果表明,5种乳酸菌培养基中MRS培养基为该菌株产细菌素的适宜培养基;最佳培养条件为种子液接种量3%(V/V)、培养基初始pH 6.0、34℃静置培养42 h;最佳培养基配方为葡萄糖添加量2 g/100 mL、酵母浸膏添加量2 g/100 mL、大豆蛋白胨添加量1.5 g/100 mL、MgSO_4添加量0.058 g/100 mL、MnSO_4添加量0.025 g/100 mL、FeSO_4添加量0.02 g/100 mL、Tween 80添加量0.08 g/100 mL、乙酸钠添加量0.5 g/100 mL、K_2HPO_4添加量0.2 g/100 mL。在此条件下,细菌素效价为1 145 IU/mL,较优化前(362 IU/mL)提高了216%

Optimization of Medium and Culture Conditions for Bacteriocin Production by Lactobacillus plantarum P158

To increase the yield of bacteriocin produced by Lactobacillus plantarum P158, the medium and culture conditions for this strain were optimized using one-factor-at-a-time and orthogonal array design methods. The bacteriostatic activity of bacteriocin against Micrococcus luteus and Pseudomonas aeruginosa and pH were used as response variables. Results showed that MRS was the most suitable for bacteriocin production among five culture media for lactic acid bacteria.The optimal culture conditions were obtained as follows: inoculum amount, 3% (V/V); initial pH, 6.0; and static culture at 34 ℃ for 42 h; the optimum medium was composed of glucose 2 g/100 mL, yeast extract 2 g/100 mL, soy peptone 1.5 g/100 mL, MgSO4 0.058 g/100 mL, MnSO4 0.025 g/100 mL, FeSO4 0.02 g/100 mL, Tween 80 0.08 g/100 mL, sodium acetate 0.5 g/100 mL, and K2HPO4 0.2 g/100 mL. Under these conditions, bacteriocin titer was 1 145 IU/mL, which was 216% higher than that (362 IU/mL) before optimization.