Degradative Pathway of Parathion-Methyl by Ochrobacterum sp. B2

The parathion-methyl degradation by Ochrobacterum sp. B2 was analyzed by thin layer chromatography, UV spectroscopy and gas chromatography-mass spectrometry analysis. The results indicated that parathion-methyl was hydrolyzed to p-nitrophenol, and this metabolite was further degraded to 4-nitrocatechol and 1,2,4-benzenetriol. B2 could grow on a medium with p-nitrophenol or 4-nitrocatechol as a sole carbon source. 50 mg/L p-nitrophenol was degraded completely in 48 h and 30 mg/L 4-nitrocatechol disappeared almost in 60 h when the initial OD600 of B2 cells was 0.02.