Induction of linoleic acid-supported benzo(a)pyrene hydroxylase activity by manganese in the white rot fungus Pleurotus pulmonarius

Linoleic acid (LA)-supported benzo(a)pyrene (BAP) hydroxylation was observed in the cytosolic fraction of the white rot fungus Pleurotus pulmonarius after incubation of the mycelium with manganese (Mn+2). Linear relationships were obtained between the indelible activity and manganese concentration added to the fungal medium, and the LA and BAP concentration added to the enzymatic reaction mixture. Cytochrome P450 inhibitors nordihydroguaiarefc acid, ketoconazole, piperonyl butoxide and carbon monoxide inhibited the induced activity. The results suggest that the presence of Mn and LA in the fungal environment could enhance P450-mediated degradation of xenobiotic compound such as BAP.