Isolation, identification and degradative properties of CP1 for chlorpyrifos

Abstract:

A bacterium, named CP1, capable of effectively degrading chlorpyrifos was isolated from activated sludge from a pesticide plant. Based on the phylogenetic analysis of 16S rRNA gene and Biolog test, the isolate CP1 was preliminarily identified as a strain of Genus Ochrobactrum. Both the orthogonal experimental design and Box-Behnken design were employed to optimized the main factors which influences the chlorpyrifos-degrading efficiency by strain CP1. The optimum conditions for chlorpyrifos biodegradation were as follows: the initial concentration of chlorpyrifos was 100 mg/L, the pH was 7.0, and the culturing temperature was 28.5 °C. Under the optimum condition, the biodegrada-tion efficiency of chlorpyrifos increased from 70.26% to 75.18%. Therefore, the optimization of chlor-pyrifos-degrading condition could improve the biodegradation efficiency of chlorpyrifos by Ochrobac-trum sp. strain CP1.

Key words:Chlorpyrifos, Biodegradation, Orthogonal experimental design, Response surface method, Optimization