Isolation, Biochemical Characterization and Growth Kinetics Studies of Chlorpyrifos and Malathion Degrading Bacterial

Among the different pesticides used worldwide, organophosphorus (OP) pesticides form the major and most extensively used class of agricultural pesticides. The toxic effects of OP were well known on humans, animals and soil microbiota. Some bacterium in Soil capable of utilizing organophosphate based pesticides as sole carbon source was isolated by selective enrichment on mineral medium containing chlorpyrifos and malathion individually. Total fifteen bacterial isolates which can capable of degrading chlorpyrifos and malathion were isolates were isolated from five different agriculture soils. KSCM-08 was proved to be high potential isolate against chlorpyrifos and malation degradation. Biochemical characteristics revealed that KSCM-08 was gram positive bacilli. Growth studies showed that KSCM-08 utilized chlorpyrifos to grow in Luria-Bertani broth containing different concentrations of chlorpyrifos at 50 -500 ppm. However, the optimum concentration that supported bacterial growth over 24 h was found to be 50-200 ppm. Further concentrations were proved to be decreasing their bacterial growth and become completely lethal at 500 ppm for both chlorpyrifos and malathion.