Biodegradation of Organochlorine Pesticide (Endosulfan and Endosulfan Sulfate) by Soil Bacteria

摘要

Aims: This analytical study confirmed the degradation of endosulfan and endosulfan sulfate by soil bacterial strains Pseudomonas putida-Bn-4a and Serratia marcescens (EF645802) in shake culture flask culture. Methods and Results: Two endosulfan-degrading bacterial strains isolated from cot- ton crop soils were identified by the results of 16S rDNA sequence analysis as Pseudo- monas putida-Bn-4a and Serratia marcescens Far-1. The degradation study was included with endosulfan mixture and endosulfan sulfate alone. The effect of supplementary car- bon (glucose) source on endosulfan degradation was also studied. The quantitative and qualitative analysis of the study was performed with HPLC and GC-MS which revealed that endosulfan ether was the end product of the metabolism. The biodegradation assays were conducted by using NSM (non-sulfur mineral salt medium) containing endosulfan (100mg I-1) and endosulfan sulfate (50 mg I-1) separately. Sodium sulfite as an alternative sulfur source was used as control. The biomass was rapidly increased to an optical den- sity of 1.2 at 600 nm in 5 days and the insecticide was consumed more than 90% within 8 days. The PCR product was eluted by using Esd gene primer in Pseudomonas putida- Bn-4a. The required gene was reported for the degradation of β–Endosulfan. The sequencing of the amplified product is underway.