Potential metabolites of dimethoate produced by bacterial degradation

Microbial degradation of pesticide has been recognized as a potential solution for the disposal of pesticide. Two bacterial strains namely Bacillus licheniformis and Pseudomonas aeruginosa, which were isolated from water and fish intestine, respectively, were allowed to grow in mineral salt solution. The acetonitrile extracts of the bacterial cultures were subjected to thin layer chromatography using two different solvent systems: hexane-chloroform-methanol and cyclohexane-acetone-chloroform. The chromatogram revealed the presence of four metabolites of dimethoate with different R-f values, in the original A aeruginosa strain using both hexane-chloroform-methanol and cyclohexane-acetone-chloroform solvent systems. Total disappearance of dimethoate spot occurred in the culture of B. licheniformis strain at day 3. Thus, the present study establishes the bacterial degradation of dimethoate and also suggests the role of bacteria in the bioremediation of pesticides.