Biodegradation of dicofol by Microbacterium sp D-2 isolated from pesticide-contaminated agricultural soil

Dicofol is an organochlorine insecticide widely used to prevent pests worldwide. Consequently, serious environmental problems have arisen from the application of dicofol. Bioremediation is an effective solution for dicofol persistence in the environment. In this study, a bacterial strain D-2, identified to genus Microbacterium, capable of degrading dicofol was isolated from dicofol-contaminated agricultural soil. This represents the first dicofol degrading bacterium isolated from this genus. Microbacterium sp. D-2 degraded 50 mg/L dicofol within 24 h at a rate of 85.1%. Dicofol was dechlorinated by D-2 and the further degradation metabolite was indentified as p,p′-dichlorobenzophenone(DCBP). Soils inoculated with Microbacterium sp. D-2 degraded 81.9% of the dicofol, while soils without D-2 only degraded 20.5% of the dicofol present. This finding suggests that strain D-2 has great potential in bioremediation of dicofol-contaminated soils.