Microbiology and Biotechnology Research: An Overview Vol. 8

A diverse array of pesticides is presently employed, but the demand for organophosphorus pesticides is increasing globally to control insects. Chlorpyrifos is a broad-spectrum, highly toxic, and chlorinated organophosphate insecticide that is synthetic in origin and is normally ester or thiol derivatives of phosphoric acid. The mode of action involves inhibiting acetylcholinesterase, leading to the accumulation of acetylcholine, causing neurotoxicity. Chlorpyrifos has been of great concern due to persistence, toxicity and accumulation in soils and groundwater. Microorganisms, playing a crucial role in bioremediation by degrading insecticides into less harmful metabolites, offer an effective approach for cleaning polluted sites. The study aims to evaluate the efficiency of Pseudomonas putida in the bioremediation of chlorpyrifos toxicity. The soil samples used for the isolation of pesticide-degrading bacteria were collected from agricultural fields, residential buildings, and Garden yards in Iraq, Al Diwaniyah, where chlorpyrifos pesticide is used extensively. Three distinct chlorpyrifos-degrading strains of Pseudomonas putidia were isolated and characterised using morphological and biochemical analysis. Strain PB1 exhibited the greatest chlorpyrifos degradation rate reach to 100% and was consequently selected for further investigation. Degradation of chlorpyrifos by strain PC1 was rapid at 20 and 37°C. Strain PB1 was able to effectively degrade chlorpyrifos in sterilised medium using high inoculum levels. The maximum degradation rate of chlorpyrifos was calculated as 0.08µg/ml to 0.002µg/ml during 6- 12 days. Bacteria such as strain PB1, which use chlorpyrifos as a carbon source, could be employed for the bioremediation of sites contaminated with pesticides. Future studies should investigate the biotechnological approaches to pesticide degradation and their practical significance under field conditions.