田口方法优化菌株产菊粉酶的培养条件

鉴定一株从菊芋根际土壤中分离出的产外切型菊粉酶活力较高的菌株C-56。通过16S r DNA序列分析构建系统发育树,初步确定菌株的分类地位,利用单因素实验和田口方法优化培养基配方。实验发现菌株C-56属于伯克霍尔德氏菌属（Burkholderia）,单因素实验确定菌株产酶的最佳碳源、氮源、无机盐分别为菊粉、酵母膏、Mg SO4·7H2O。应用田口方法优化菌株的培养基,统计学分析发现菊粉对菌株产酶的影响最大,最佳培养基配方为菊粉50 g/L,酵母浸粉20 g/L,Mg SO4·7H2O 6 g/L,p H6.0。在最佳条件下获得的菊粉酶活力为（29.34±1.95）U/m L,比初始菊粉酶酶活力（6.25±0.84）U/m L提高了3.69倍。 

Optimization of medium components for inulinase production of a strain using Taguchi method

A strain with high inulinase productivity named C- 56 which was isolated from Jerusalem artichoke rhizosphere soil was identified.Analysis of 16 S rRNA gene sequence indicated that strain C- 56 was belonged to genus Burkholderia.The optimal carbon sources,nitrogen sources,and inorganic salt were identified as inulin,yeast extract,Mg SO4·7H2O through single factor test,respectively. The optimization of inulinase production from strain C-56 was studied by Taguchi method. Statistical analysis of the experimental data indicated that inulin was the most significant factor for inulinase production. The optimal medium compositions for maximizing the inulinase production were established as 50 g / L inulin,20 g / L yeast extract,6 g / L Mg SO4·7H2O,initial p H6.0. Under optimum conditions,( 29.34 ± 1.95) U / m L of inulinase activity were obtained,which increased about 3.69 times compared with the initial enzyme activity( 6.25 ± 0.84) U / m L.