Pesticide lambda-cyhalothrin degradation using mesorhizobium sp. (s1b) and bartonella sp. (s2b) strains isolated from cotton crop

Lambda-cyhalothrin (LC), synthetic pyrethroid pesticide is used to control a wide range of pests in variety of agricultural fields. Pesticides are potentially harmful environmental pollutants and pose serious threat to human health. Very limited options are available for environment friendly removal of LC. Interestingly, soil microbes have been known to possess remarkable genetic makeup that helps them to perform vital job in cleaning-up harmful pollutants from the environment. In present study, two LC-degrading bacteria viz. Mesorhizobium sp. strain S1B (Accession no. gb|MF471843|) and Bartonella sp. strain S2B (Accession no. b|MF471844|) were isolated by soil enrichment technique from cotton crop soil and characterized taxonomically using conventional methods and molecular PCR-based 16S rRNA sequence homology. The bacterial strains S1B and S2B achieved 29% and 40% removal of LC (conc. 250 mg/L, w/v), with maximum growth absorbance (OD) of 1.19 +- 0.06 and 1.13+- 0.09, respectively, during 20 days of incubation at 30 degree C and agitation 200 rpm under experimental laboratory circumstances. The percent removal of LC was estimated using UV-Vis Spectroscopy at 287 nm (? max) against the standard curve plotted at different LC concentrations. The bacterial isolates of present study have exhibited substantial efficiency for environmental biodegradation of the pesticide. (author)