Remedial potential of bacterial and fungal strains (Bacillus subtilis, Aspergillus niger, Aspergillus flavus and Penicillium chrysogenum) against organochlorine insecticide Endosulfan.

Endosulfan, an organochlorine insecticide, is known to cause detrimental effects to the environment and human health due to its excessive usage. Its highly toxic nature calls for an environmental-friendly approach for its detoxification. Environmental transformation of Endosulfan was assessed through biodegradation by isolated and cultured soil microbes (Bacillus subtilis (BS), Aspergillus niger (AN), Aspergillus flavus (AF) and Penicillium chrysogenum (PC)). Degradation of 10 mg/L Endosulfan was determined in aqueous solution at regular time intervals and analysed by gas chromatography-mass spectrometry for 35 days. BS and AN displayed substantial potential to degrade Endosulfan and subsequently transform it into its daughter products (95 and 77%, respectively). Endosulfan transformation followed first-order reaction kinetics. Chromatogram peaks revealed less toxic metabolites by Endosulfan transformation (Endosulfan diol, Endosulfan ether, Endosulfan hydroxyether and Endosulfan lactone). Half-life of Endosulfan obtained by various strains utilised in the experiments was in the order, PC (69) > AF (34.6) > AN (17.3) > BS (11.5) days. Statistical analysis was performed in MINITAB to evaluate the significance of results. Bioaugmentation of contaminated sites with such efficient microbes can facilitate rapid pesticide transformation and decontamination of the environment.