利用响应面优化Klebsiella variicola对麻疯树籽饼粕佛波酯的固态发酵降解

Optimization of response surface for degrading phorbol esters in Jatropha curcas seed cake through Klebsiella variicola solid-state fermentation

为降解麻疯树籽饼粕中的毒性成分佛波酯,利用Klebsiella variicola进行固态发酵.采用单因素实验法研究了发酵温度、接种量、初始加水量、发酵时间对佛波酯降解率的影响.在此实验结果基础上,利用Design Expert8.0软件进行分析建立了发酵温度、接种量、初始加水量3个因素对佛波酯降解率影响的优化模型.该模型极显著(P<0.001),拟合度良好.经实验证实,在发酵温度为37℃、接种量33%(V/m)、初始加水量为105%(V/m)条件下发酵48 h,佛波酯降解率可达到84.30%,另一种毒性物质curcin的降解率可达63.21%.研究表明,利用响应面优化K.variicola固态发酵麻疯树籽饼粕过程,既可提高佛波酯降解率,也可降解curcin,具有生产指导意义.

This study aimed to optimize the degradation？rate of phorbol ester？of Jaropha curcas seed cake through solid-state fermentation of Klebsiella variicola. Firstly, by the single factor experiments, the effects of fermentation temperature, inoculum amount, initial？amount of water and？fermentation？time？were determined. Then Design Expert8.0 was used to analyze and optimize the model of phorbol esters degradation rate by three factors （fermentation temperature,？inoculum amount and？initial？amount of water） through response surface methodology. A model was then set up, its validity verified, and the degradation？rate of curcin measured. The？model was significant？（P 〈 0.001）,？fitting well. In confirming experiments,？under the condition of？fermentation temperature 37 oC,？inoculation？（V/m） 33%,？the initial？water content？105%？（V/m）, after？fermentation for 48 hours, the？phorbol ester？degradation？rate was 84.30% and curcin degradation？rate 63.21%. The results suggested that with optimization of the response surface methodology, K. variicola can degrade phorbol ester？efficiently and at the same time degrade curcin.