Biodegradation of Malathion Earthworm Coelomic Fluid Isolates Bacteria from Sugarcane Field, Theni District,

Abstract

The present study investigates the biodegradation of malathion by bacterial isolates obtained from earthworm coelomic fluid. The isolates were identified as Acinetobacter sp., Pseudomonas sp., Bacillus sp., and Klebsiella sp., based on morphological and biochemical characteristics. UV–Vis spectroscopic analysis showed a characteristic malathion peak at 252 nm, which gradually decreased and shifted with increasing incubation time, indicating degradation. Maximum degradation was observed after 28 days, with significant reduction in absorbance among all isolates. FTIR analysis revealed notable changes in functional groups, including amide, ester, carbonyl, and C–O groups, confirming the breakdown of malathion into intermediate compounds over time. GC–MS analysis further supported these findings by identifying various metabolites such as carbetamide, methoprene derivatives, nitenpyram, etofenprox, cypermethrin, permethrin, pyridate, acetamiprid, and DEHP, indicating transformation into simpler and less toxic compounds. Overall, the results demonstrate that bacterial isolates from earthworm coelomic fluid possess significant potential for the biodegradation of malathion and can be effectively utilized in the bioremediation of pesticide-contaminated environments.