Optimization of culture condition of Metarhizium anisopliae for destruxin A production by response surface methodology

Objective  To raise the destruxin A production of Metarhizium anisopliae by optimizing culture conditions of liquid fermentation.

Method  Experiments were designed by response surface methodology (RSM). The key factors affecting the liquid fermentation were screened by Plackett-Burman design and central composite design.

Result  A model with high fitting degree and small error was obtained. The optimum culture condition of this model was 22.7 g·L^–1 sucrose, 13.4 g·L^–1 peptone and 9.70 d for fermentation. The maximum predicted concentration of destruxin A was 6.90 μg·mL^–1, while the actual measured concentration was 6.89 μg·mL^–1.

Conclusion  The results can provide a theoretical basis for large-scale fermentation of M. anisopliae and production of crude toxin, which can potentially enable the widespread development and application of crude toxin.