Biodegradation of beta-cyfluthrin by fungi.

Five fungal species, namely, Trichoderma viride strain 5-2, T. viride strain 2211, Aspergillus niger, A. terricola, and Phanerochaete chrysoporium were screened for degradation study of beta-cyfluthrin. Each fungal species was allowed to grow in Czapek dox medium containing beta-cyfluthrin (5 mg/mL) as the major carbon source of the medium. The highest degradation of beta-cyfluthrin was observed by T. viride 5-2 (T(1/2) = 7.07 days), followed by T.viride 2211 (T(1/2) = 10.66 days). The degradation of beta-cyfluthrin followed first-order kinetics with a fast degradation rate during first 7 days of growth of the fungi. In the case of T. viride strain 5-2, five degradation products were isolated after 20 days of growth of the fungi, out of which three products were identified as alpha-cyano-4-fluorobenzyl-3- (2,2-dichlorovinyl)-2,2-dimethyl cyclopropane carboxylate, alpha-cyano-4-fluoro-3-phenoxy benzyl alcohol, and 3(2,2-dichlorovinyl)-2,2-dimethyl cyclopropanoic acid.