Biodegradation of chlorpyrifos and its hydrolyzing metabolite 3,5,6-trichloro-2-pyridinol by Sphingobacterium sp. JAS3

• Sphingobacterium sp. JAS3 efficiently degraded chlorpyrifos and TCP.
• Degradation product benzene, 1,3-bis(1,1-dimethylethyl) was obtained.
• JAS3 degraded chlorpyrifos and TCP in soil devoid of nutrients.

Biodegradation of chlorpyrifos and its metabolite 3,5,6-trichloro-2-pyridinol (TCP) were studied in aqueous medium and in soil with a novel bacterial strain JAS3. The molecular characterization based on 16S rRNA sequence analysis revealed the strain JAS3 as Sphingobacterium sp. The strain JAS3 was able to grow in minimal salt medium (MSM) supplemented with 300 mg l−1 of chlorpyrifos as sole carbon source. The degradation of chlorpyrifos and its primary metabolite TCP were examined by HPLC. After 5 d, Sphingobacterium sp. JAS3 degraded chlorpyrifos and its metabolite TCP to benzene, 1,3-bis(1,1-dimethylethyl) was analyzed by GCMS. Degradation of chlorpyrifos and TCP in soil with and without addition of nutrients was also studied. The ability to degrade chlorpyrifos makes this strain a useful candidate for remediation of pesticide contaminated sites.