基于响应面法优化一株低温耐盐芘降解菌共代谢条件的研究

摘要

为了提高低温耐盐芘降解菌DYC-1的共代谢降解率,在已获悉菌株降解最优pH值、初始浓度、摇床转速和接菌量的情况下,利用Plackett-Burman实验设计筛选出影响菌株DYC-1降解PAHs芘的3个外加碳源显著影响因子为葡萄糖、水杨酸和菲,用最陡爬坡实验逼近3个因子的最大响应区域,采用Box Behnken实验设计及响应面法分析,确定其最优共代谢条件为:葡萄糖225.83mg/L,水杨酸112.10mg/L,菲198.06mg/L;在此条件下培养10d,芘降解率可达到50.69％,相对于不加共代谢底物时提升了23.14％.表明响应面法对菌株共代谢条件的优化合理可行.%In order to enhance pyrene bacteria cometabolism degradation rate under low temperature and high salt environment,under the circumstances of learned optimal pH,initial concentration of pyrene,shaking rates of rocking bed,inoculating dosage,Plackett-Burman Design was conducted and glucose,salicylic acid and phenanthrene were identified as main factors.These factors were approached to optimal region by steepest ascent design.Then optimal degradation condition(glucose,225.83mg/L;salicylic acid,112.10mg/L;phenanthrene,198.06mg/L) was established by Box-Behnken design and reponse surface analysis.Degradation rate under the optimal consition was 50.69％ after 10days,enhanced 23.14％ compare to the condition of without cometabolism degradation substrate.Experimental results also showed that the method of optimization for bacteria cometabolism degradation is reasonable and feadible.