CCD响应面设计优化米曲霉产果糖基转移酶的发酵工艺

Optimization of fermentation technology for production of fructosyltransferase with Aspergillus oryzae using CCD response surface methods

本文用蔗糖、豆粕粉、玉米粉作为基础培养基,对产果糖基转移酶的米曲霉诱变融合菌株RⅢ-7进行发酵实验,通过Plackett-Burman优化实验,得到影响其发酵的3个显著因素,分别为蔗糖浓度、豆粕粉浓度、转速;再通过中心复合设计(CCD)响应面设计进一步优化米曲霉产果糖基转移酶的发酵工艺,实验结果表明,蔗糖、豆粕粉和转速之间存在着交互作用,其中豆粕粉浓度与转速之间的交互作用显著,得到最优工艺参数为:蔗糖浓度为5.95%、豆粕粉浓度为1.60%、转速为165 r/min。经验证,在最优发酵工艺条件下,米曲霉产果糖基转移酶酶活力达到870.21 U/g,与预测值895.68 U/g接近,误差为0.028%。

In order to produce fructosyltransferase in large scale,it is necessary to study and optimize the process conditions of Aspergillus oryzae strains fermentation. Using sucrose,soybean meal powder and corn flour as the basic medium for fructosyltransferase synthesis in the cells,three significant factors that affect the fermentation course were selected through the Plackett- Burman optimization experiment.With analysis of the central composite design（ CCD） response surface methods,the fermentation process has been further optimized and the results showed that： there were interactions between the concentration of sucrose,soybean meal powder and the rotation speed.The interaction between the concentration of soybean meal powder and the rotation speed was mainly significant.The best technical parameters were obtained as followed： the concentration of sucrose was 5.95%,the concentration of soybean meal powder was 1.60%,and the rotation speed was 165 r / min. Under the optimal condition of fermentation,the enzyme activity of fructosyltransferase produced by fusion strain Aspergillus oryzae RIII-7 reached 870.21 U / g.It is close to the predictive value of 895.68 U / g,with an error of 0.028.