植物乳杆菌ZU018增殖培养基的优化

本研究以植物乳杆菌ZU018为研究对象,最终活菌数为主要参考指标,对其发酵培养基成分进行了优化。采用单因素实验选择碳源、氮源的种类及优化浓度,通过部分因子试验设计初步确定了麦芽糖、酵母浸粉及柠檬酸三铵为培养基中最主要的三个影响因素,进一步运用最陡爬坡试验及Box-Benhnken试验设计对培养基组分进行优化。结果表明,最佳优化培养基配方为:麦芽糖30.03 g/L、酵母浸粉37.50 g/L、牛肉浸粉25.00 g/L、柠檬酸三铵4.39 g/L、磷酸氢二钾2.00 g/L、乙酸钠5.00 g/L、硫酸镁 0.20 g/L、硫酸锰0.05 g/L以及1.00 g/L的吐温80。最终发酵液中植物乳杆菌ZU018活菌数相比优化前提高4.86倍,达到10.67×109 CFU/mL,为后续植物乳杆菌高密度发酵及应用提供了理论依据。

Optimization of Lactobacillus plantarum ZU018 Proliferation Medium

In this study, Lactobacillus plantarum ZU018 was the research object, the final number of viable cells was as the main reference index, and its fermentation medium was optimized. The single factor experiment was used to select the type and concentration of carbon source and nitrogen source. Maltose, yeast extract and triammonium citrate as the main factors of the medium were preliminarily determined by partial factor test design. The path of steepest ascent and Box-Behnken test design were used to optimize the composition of the medium.The results showed that the optimal optimized medium formula was:Maltose 30.03 g/L, yeast extract 37.50 g/L, beef extract 25.00 g/L, triammonium citrate 4.39 g/L, potassium hydrogen phosphate anhydrous 2.00 g/L, sodium acetate anhydrous 5.00 g/L, magnesium sulphate 0.20 g/L, manganese sulfate 0.05 g/L, and 1.00 g/L tween 80. Compared with that before optimization, the number of viable bacteria in the final fermentation broth of Lactobacillus plantarum ZU018 increased by 4.86 times reaching 10.67×109 CFU/mL, which would provide a theoretical basis for the subsequent high-density fermentation and application of Lactobacillus plantarum.