一株藤黄微球菌高密度培养研究

Research on High-density Cultivation of M.luteus

为了提高细菌发酵型腐乳生产菌株——藤黄微球菌(M.luteus)KDF2的菌数,采用响应面法对其发酵培养基和采用单因子试验法对其培养条件进行优化。结果表明:优化后的培养基配方为蔗糖11.57g/L;蛋白胨∶酵母浸粉为1∶1为32.13g/L;磷酸氢二钾为8.09g/L,在此条件下,藤黄微球菌(M.luteus)KDF2菌落总数为4.79×109 cfu/mL。优化藤黄微球菌(M.luteus)KDF2的培养条件为最适温度30℃;pH 8.0;装液量50 mL/250 mL;振荡频率150r/min;最终的活菌数5.42×109 cfu/mL。此研究成果为缩短腐乳后酵周期及直装腐乳发酵工艺的后续研究奠定了基础。

In order to improve the number of bacterial-fermented bean curd production strain of M. luteus KDF2, the response surface methodology and the single factor test methodology are respectively used to optimize the fermentation medium and culture conditions of M.luteus KDF2.The optimized formula of culture medium is as follows：sucrose of 11.57 g/L,ratio of peptone to yeast extract of 1 ∶ 1 and the total concentration of 32.13 g/L,concentration of dipotassium hydrogen phosphate of 8.09 g/L.Under such conditions,the total number of colonies of bacteria reaches 4.79 ×10 ^9 cfu/mL.The cultivation conditions of M.luteus KDF2 show that the optimum temperature is 30 ℃,the optimum pH is 8.0,the loaded liquid is 50 mL/250 mL and the oscillation frequency is 150 r/min,under such conditions,the final total number of bacteria colonies is 5.42 ×10 ^9 cfu/mL. This research has laid the foundation for follow-up study of shortening the fermentation cycle and production process of direct-loaded fermented bean curd.