一株产内切菊粉酶菌株培养条件的响应面优化

Optimization of medium components for an endoinulinase strain by response surface methodology

从新疆石河子盐碱地菊芋生长根际土壤中,分离筛选得到10株具有内切菊粉酶活力的菌株,复筛得到1株高产内切菊粉酶活力菌株,将其命名为G-60。在单因素实验的基础上,采用Plackett-Burman实验法对8个因素进行了显著因素的筛选,结果表明,菊粉浓度、蛋白胨浓度和装液量对内切菊粉酶酶活影响显著;通过最陡爬坡实验及Central Composite Design设计进一步优化,得到最佳发酵产酶条件为:菊粉浓度66.5g/L、蛋白胨浓度29.1g/L、装液量49.38mL,内切菊粉酶活力达24.62U/mL,与优化前相比提高了1.55倍。

The strain with high endoinulinase productivity was screened, named G-60 which was collected from the root soil of Jerusalem artichoke in Shihezi city of Xinjiang province.A Plackett-Burman design was used to evaluate the influence of eight factors.The results showed that inulin added amount, content of the peptone and the liquid medium volume played an important role in influencing the endoinulinase activity.Then the path of steepest ascent and the central composite design were suitable for further optimization, the optimal concentration of the variables were determined as.Inulin 66.5g/L, Peptone 29.1 g/L, and liquid medium volume 49.38mL.Under this condition, the endoinulinase activity was increased to 24.62U/mL,which was improved by 1.55 times than before optimization.