Potential of the white-rot fungus pleurotus pulmonarius F043 for degradation and transformation of fluoranthene

Abstract

Fluoranthene, a four-ring polycyclic aromatic hydrocarbon that is possible genotoxic in nature, has been used as an indicator for assessing polycyclic aromatic hydrocarbon (PAH)-containing pollutants. Microbial degradation is one of the promising methods in removing up PAH-contaminated environments. White-rot fungi have showed the ability to degrade a wide range of PAHs. This study aimed to investigate enzyme production, fungal biomass, and glucose utilization during the biodegradation process of fluoranthene by a white-rot fungus Pleurotus pulmonarius F043 and to identify the metabolites produced in the degradation process. The extracellular ligninolytic enzyme system of the fungi, producing laccases and peroxidases, was directly linked to the biodegradation of fluoranthene. The production of ligninolytic enzymes during fluoranthene degradation was related to an increase in the biomass of Pleurotus pulmonarius F043. Fluoranthene removal decreased with an increase in fluoranthene concentrations. The highest biomass production of Pleurotus pulmonarius F043 (≥ 4 400 mg L-1) was found in the 10 mg L-1 fluoranthene culture after 30 d of incubation. Two fluoranthene metabolites, naphthalene-1,8-dicarboxylic acid and phthalic acid, were found in the process of fluoranthene degradation. Laccase was revealed as the major enzyme that played an important role in degradation process. Suitable conditions must be found to promote a successful fungal biotransformation augmentation in liquid culture.