Metabolism of Chloronicotinyl Neonicotinoid Insecticides by Fungi Penicillium oxalicum IM-3

A strain of filamentous fungus capable of degrading acetamiprid,an insecticide of chloronicotinyl neonicotinoid series,was isolated from soil and named as Strain IM-3.IM-3 was identified as Penicillium oxalicum by morphology and 18S rDNA sequence analysis.In the medium of mineral salts,incubated for 14 days,P.oxalicum degraded 41.6% of AAP and 14.1% of imidacloprid;but nil of thiacloprid and nitenpyram.HPLC and LC-MS/MS analysis revealed that the metabolic pathway of AAP by P.oxalicum IM-3 was N-demethylation of AAP to form IM 2-1 and oxidative cleavage of cyanoimine moiety to form IM 1-3.