Abstract—Endosulfan is a characteristic pesticide having both chlorine and sulphur as functional groups, effective in controlling a large spectrum of pests. It is sprayed as contact insecticide on food crops. Residues of α and β endosulfan have varying half life and persist in air, water and soil along with their degradation products. The present study aimed at delineating endosulfan residues in soil, representing samples drawn from agricultural fields during winter season. The samples after pre-treatment were subjected to enrichment of the residues. The residues were estimated by GC-ECD method. The concentration of α endosulfan ranged from 0.1 mg to 29 mg/Kg, the levels of β Endosulfan ranged from 0.1-167 mg/kg, and that of Endosulfan sulphate ranged from 0.12-27 mg/Kg respectively. This study once again proves the highly persistant nature of the residues of endosulfan in soil and hence the need to find measures to remove them from the environment.
The microorganisms present in this soil were found to possess the ability to degrade endosulfan as they are chronically exposed to it. Up to 70% of endosulfan and 100% of Endosulfan sulphate degradation were observed. Hence, organisms isolated from endosulfan contaminated soils by the process of enrichment can be used as bio remediating agents for soil and water.

Index Terms—Endosulfan, persistence, enrichment.

V.Krishnamurthy and Sarah Sunitha are with Department of Biotechnology, PES Institute of Technology, BSK III Stage, Bangalore-560085, India (e-mail: profvkm55@yahoo.com, Sarah Sunitha: sarahjohn125@gmail.com).
Riaz Mahmood is with Department of Biotechnology and Bioinformatics, Kuvempu University, Shankarghatta, Shimoga-577451 India (e-mail: riaz_sultan@yahoo.com).

Cite: Sarah Sunitha, V. KrishnaMurthy, and Riaz Mahmood, "Degradation of Endosulfan by Mixed Bacterial Cultures Enriched from Endosulfan Contaminated Soils of Southern India," International Journal of Bioscience, Biochemistry and Bioinformatics vol. 2, no. 1, pp. 31-35, 2012.