Degradation and Metabolite Profiling of Benz (a) Anthracene, Dibenz (a, h) Anthracene and Indeno [1, 2, 3-cd] Pyrene by <i>Aspergillus terricola</i>

Abstract

Mycoremediation of low molecular weight polycyclic aromatic hydrocarbons (PAH) is well studied. This study highlights the degradation of high molecular weight PAH (HMW-PAHs): Benz (a) anthracene (BAA), Dibenz (a, h) anthracene (DBA), and Indeno pyrene (IND) by Aspergillus terricola var americanus. The metabolism of the HMW-PAHs by this fungus was investigated in liquid submerged culture added with 60 mg/L of each compound. Depletion of BAA, DBA, and IND was 94.80, 90.16, and 93.80%, respectively, after 10 days of culture. Fungal broth solvent extracts were analyzed for the presence of metabolites by gas chromatography mass spectrometry and the extracellular enzymes produced were also assayed. The coexistence of two metabolic pathways, cytochrome P450 monooxygenase and ligninolytic pathway were identified. A high laccase activity was observed in BAA cultures on day 4 when compared to other PAH's studied. In conclusion, A. terricola might be a promising fungus for bioremediation of HMW-PAH mixtures co-metabolically.