响应面法优化黑曲霉产葡萄糖氧化酶条件

运用响应面法对黑曲霉(Aspergillus niger)产葡萄糖氧化酶以及发酵条件进行了优化。根据单因素实验结果，利用Plackett-Burman设计对影响其产酶相关因素进行评估并筛选出具有显著效应的3个因素：葡萄糖，玉米浆和碳酸钙。用最陡爬坡试验逼近以上3个因子的最大响应区域后，采用Box-Behnken设计以及响应面分析法，确定其优化后发酵条件为(g/L)：葡萄糖172.11、玉米浆11.05、碳酸钙52.29、牛肉蛋白胨3.5、（NH₄）H₂PO₄ 0.5、KCl 0.15、MgSO₄·7H₂O 0.125、FeSO₄·7H₂O 0.125，220r/min，30℃培养48h。优化后的葡萄糖氧化酶酶活达786.3U/g，比在种子培养基中酶活350.5U/g提高了2倍左右。

Optimization of glucose oxidase production by fermentation with Aspergillus niger using a response surtace method

Response surface methodology(RSM) has been employed to optimize the culture medium for glucose oxidase(GOD) production by Aspergillus niger.Firstly,according to the results of a mono-factor experiment,a Plackett-Burman design was used to investigate the effects of different factors in the ferment medium,with the three statistically significant factors being identified as: glucose,corn steep liquor and CaCO3.Secondly,the steepest ascent procedure was employed to define the optimal response region for these three factors.Finally,the Box-Behnken method was employed to design the reaction system.The results of the experiments were analyzed by RSM with Minitab 15.0 software.The optimal fermentation medium for production of GOD consisted of the following(g/L): glucose 172.11,corn steep liquor 11.05,CaCO3 52.29,beef peptones 3.5,(NH4)H2PO4 0.5,KCl 0.15,MgSO4·7H2O 0.125,FeSO4·7H2O 0.125,stirring rate of 220r/min,with incubation at 30℃ for 48h.GOD production after optimization was increased by a factor of about two,from 350.5U/g to 786.3U/g.