红色诺卡菌固体培养基配方的优化

Optimization of Nocardia rubra Solid Medium Formulation

应用响应面优化设计法优化固体培养基配方,增大红色诺卡菌的固体培养细胞生物量。首先用Plackett-Burman法从现有培养基组分中找到影响红色诺卡菌细胞生物量的关键因素,再通过最陡爬坡法确定细胞生物量最大的配方,用作中心组合设计(Central Composite Design, CCD)实验的基础起始值,拟合数学模型方程,最后找到最优组分的组合。优化的配方转移至企业实施放大实验,对结果进行验证和比较。试验结果表明,培养基各组分中影响红色诺卡菌细胞生物量的关键因素为蛋白胨、NaCl、牛肉膏;最优固体培养基配方:蛋白胨42 g/L、牛肉膏8 g/L、NaCl 1.2 g/L、甘油10 mL/L、Na_(2)HPO_(4)·12H_(2)O 0.3 g/L、琼脂20 g/L。在细胞生物量方面最优固体培养基配方比原配方高104%。响应面优化设计可用于提高红色诺卡菌细胞生物量固体培养基的优化,也为红色诺卡菌培养条件、液体发酵的优化研究提供参考。

Solid medium formula was optimized using response surface methodology to increase the solid culture biomass of Nocardia rubra Nr-8206. First, discovered the key factors affecting the biomass of N. rubra Nr-8206 from existing medium formula by Plackett-Burman method, then determined the formula with the largest biomass adopted the steepest ascent, used as basic starting value of central composite design(CCD) experiment to fit the mathematical model equations, finally was to find the optimal combination. The optimized formula was then transferred to the enterprises to apply enlargement experiment and conduct verification and comparison of the results. The results showed that key factors that affected the biomass of N. rubra Nr-8206 in each medium component were: peptone, NaCl, and beef extract;and the optimal solid medium formula was: peptone 42 g/L, beef extract 8 g/L, NaCl 1.2 g/L, glycerol 10 mL/L, Na_(2)HPO_(4)·12 H_(2)O 0.3 g/L, agar 20 g/L. In terms of cell biomass, the optimal solid medium formulation was higher by 104% as compared with the original formulation. Therefore, response surface methodology can be used to optimize the solid medium for improving the biomass of N. rubra Nr-8206, and also provide a basis for the optimization of N. rubra Nr-8206 culture conditions and liquid fermentation.