关键词: 降解, 二苯并噻吩, 假单胞菌, 响应曲面法, Box–Behnken设计

Abstract: Abstract: In this research, the degradation of dibenzothiophene (DBT) was investigated by Pseudomonas sp. LKY-5 isolated from oil contaminated soil. The response surface methodology (RSM) based on Box–Behnken design (BBD) was applied for evaluating the interactive effects of four independent variables including substrate concentration, temperature, pH and agitation rate on the DBT removal response. A total of 29 experiments for four factors at three levels were conducted in present study. A second-order regression model was then developed, and the analysis of variance (ANOVA) illustrated that the proposed quadratic model could be utilized to navigate the design space. The value of determination coefficient (R2=0.9534) indicated a satisfactory agreement between the quadratic model and the experimental data. It was found that DBT removal was more significantly affected (P<0.0001) by substrate concentration compared with other three parameters. The 100% degradation of DBT could be obtained by Pseudomonas sp. LKY-5 at substrate concentration of 100 mg/L.

Key words: degradation, dibenzothiophene, Pseudomonas sp., response surface methodology, Box–Behnken design