响应面法优化前包被屎肠球菌超声计数条件的研究

Study on the optimization of ultrasonic extraction conditions of the encapsulated Enterococcus faecalis pre-fermented using response surface methodology

发酵前包被微胶囊化培养的屎肠球菌具有耐受性强、效价稳定的优点,但其活菌数检测难度阻碍了其推广使用。本研究以前包被屎肠球菌为原料,综合考虑操作方便、时间及计数结果,优化前包被肠球菌活菌超声振荡计数方法,选择不同试管的超声时间、超声功率为自变量,总菌落数(cfu/g)为响应值,采用Box-Behnken设计方法,研究各自变量及其交互作用对计数结果的影响。结果显示,响应面法优化所得最佳计数条件为:原菌液梯度稀释后,超声功率240 W、10^(-1)超声7 min、10^(-2)超声45 s。此条件下,前包被屎肠球菌计数结果最佳,为5.53×10^(11) cfu/g。本结果与预测值相近,故选用此方法作为后期前包被屎肠球菌活菌计数方法。

To optimize the method of counting ultrasonic oscillating oscillations of encapsulated Enterococcus faecalis pre-fermented,considering the convenience of operation,time and counting results,the effect of ultrasonic time and power on the clump counts of the enterococcus faecium have been studied in this paper with Box-Behnken design. The ultrasonic time and ultrasonic power of different test tubes were selected as independent variables and the total number of colonies（cfu/g）is the response value. The results showed that response surface methodology was reliable,and the optimal counting conditions were as follows ：after dilution with the original bacterial solution,at 240 W,ultrasonic processing 7 min of 10^-1,ultrasonic processing 40 s of 10^-2. Under the optimal condition,the encapsulated E. faecium pre-fermented count is 5.53×10^11 cfu/g. This result is close to the predicted value,so this method was selected as the method of counting the viable bacteria of the enterococci before the late period.