响应面法优化短杆菌素的发酵

Fermentation of Tyrothricin by Response Surface Methodology

为了提高短芽孢杆菌Bacillus Brevis(ATCC 8185)发酵液中的短杆菌素产量,采用一系列试验设计法对其发酵培养基及培养条件进行了优化。先用Plackett-Burman设计从8个因子中筛选出对短杆菌素产量有显著影响的因素,再用最陡爬坡试验确定3因素的取值范围,最后使用中央组合设计及响应面方法进一步优化。通过优化过程筛选出的影响因素取值为:酪蛋白胨10.28 g/L,NaCl 4.62 g/L和酵母浸粉11.03 g/L。在此优化培养条件下,发酵液中短杆菌素的质量浓度从优化前的265.32μg/mL提高到594.50μg/mL。

Sequences of experimental designs are applied to optimize medium and fermentation conditions,in order to enhance the tyrothricin production by Bacillus Brevis（ATCC 8185）.A significant influence of peptone casein,NaCl and yeast extract on tyrothricin yield is evaluated by Plackett-Burman（PB） design.The optimal concentration range of the three factors is examined by the steepest ascent method and the medium formulation is optimized by the central compose design（CCD） and response surface methodology（RSM）.Under the optimal conditions,the concentrations of the selected factors are determined as casein peptone 10.28 g/L,NaCl 4.62 g/L and yeast extract 11.03 g/L.Tyrothricin production is obtained coincidence with the predicted value and the model is proven to be adequate.The enhancement of tyrothricinfrom 116.14 μg/mL to 594.50 μg/mL is achieved within the optimization procedure.