Pyrene degradation and copper and zinc uptake by Fusarium solani and Hypocrea lixii isolated from petrol station soil

Aims:This study aimed to isolate and identify potential polycyclic aromatic hydrocarbon (PAH)-degrading and/or metal-tolerant fungi from PAH-contaminated and metal-contaminated soils.Methods and Results:Pyrene-degrading fungi were isolated from contaminated soil and tested for metal (Cu, Zn and Pb) compound solubilization and metal accumulation. Three strains of Fusarium solani and one of Hypocrea lixii were able to degrade more than 60% of initial supplied pyrene (100 mg l-1) after 2 weeks. The isolates were grown on toxic metal (Cu, Pb and Zn)-containing media: all isolates accumulated Cu in their mycelia to values ranging from c. 5 center dot 9 to 10 center dot 4 mmol per kg dry weight biomass. The isolates were also able to accumulate Zn (c. 3 center dot 7-7 center dot 2 mmol per kg dry weight biomass) from zinc phosphate-amended media. None of the isolates accumulated Pb.Conclusions:These fungal isolates appear to show promise for use in bioremediation of pyrene or related xenobiotics and removal of copper and zinc from wastes contaminated singly or in combination with these substances.Significance and Impact of the Study:Microbial responses to mixed organic and inorganic pollution are seldom considered: this research highlights the abilities of certain fungal strains to interact with both xenobiotics and toxic metals and is relevant to other studies on natural attenuation and bioremediation of polluted sites.