响应面法优化泡盛曲霉产抗肿瘤活性物质发酵工艺

Optimization in Fermentation Process for Producing Antitumor Active Substances by Aspergillus awamori Using Response Surface Methodology

为提高喜树内生真菌发酵产10-羟基喜树碱(10-hydroxyamptothecin,HCPT)能力,以泡盛曲霉CS24为发酵菌种,以HCPT产量为考核指标,通过单因素实验和Plackett-Burman实验,筛选出发酵温度、通风量和玉米浆干粉含量等3个影响发酵的显著因素;通过最陡爬坡实验确定中心组合设计的水平中心;通过Box-Behnken实验、响应面分析获得最优培养基为:玉米浆干粉13 g·L^(-1)、花生饼粉25 g·L^(-1)、蔗糖10 g·L^(-1)、糊精30 g·L^(-1)、麦芽糖15 g·L^(-1)、Mg ^(2+)0.5 mmol·L^(-1);最优发酵工艺为:发酵温度29℃、通风量0.6 vvm、搅拌转速380 r·min^(-1)、初始pH值5.0。在此条件下,HCPT产量达到171.6 mg·L^(-1),比优化前(94.6 mg·L^(-1))提高了44.9%,为工业化发酵生产HCPT奠定了理论和实践基础。

In order to improve the production capacity of 10-hydroxyamptothecin(HCPT)by endophytic fungi of Camptotheca acuminate Decne.,using HCPT yield as an evaluation index,we selected three factors affecting fermentation of Aspergillus awamori CS24,such as fermentation temperature,ventilation rate,and content of corn pulp dry powder by single-factor experiments and Plackett-Burman experiments.Moreover,we determined the horizontal center of the center combination design through the steepest climbing experiments.Furthermore,we optimized the fermentation process by Box-Behnken experiments and response surface analysis.The results show that the optimal medium formula is obtained as follows:corn pulp dry powder 13 g·L^(-1),peanut cake powder 25 g·L^(-1),sucrose 10 g·L^(-1),dextrin 30 g·L^(-1),maltose 15 g·L^(-1),and Mg ^(2+)0.5 mmol·L^(-1);the optimal fermentation conditions are obtained as follows:the fermentation temperature of 29℃,the ventilation rate of 0.6 vvm,the stirring speed of 380 r·min^(-1),and the initial pH value of 5.0.Under above conditions,the HCPT yield reaches 171.6 mg·L^(-1),which is 44.9%higher than that before optimization(94.6 mg·L^(-1)).This study lays a theoretical and practical foundation for industrial fermentation production of HCPT.