The bioremediation potentials of fungal species isolated from soils polluted by petroleum products in Cross River University of Technology, Calabar, Nigeria. – M. E. Eja, G. E. Arikpo and S. M. Udo
A comparative assessment of the biodegradative abilities of fungal species isolated from Nigerian soils contaminated with engine oil, diesel and petrol was carried out. Microbiological and physico-chemical properties such as moisture content, pH, particle size, total hydrocarbon (THC), organic carbon, nitrogen and phosphorus contents of the contaminated soils were also investigated, and the biodegradative potentials of the isolated fungal species were determined by measuring the optical densities (OD) of the fungal cultures spectrophotometrically. Incidence of fungal growth was highest in diesel-contaminated soil (41%) after an initial response to the diesel toxic effect. Among the fungal isolates, Saccharomyces, Aspergillus, Cladosporium, Rhizopus, Mucor and Penicillium species, Cladosporium species from diesel-contaminated soil had the highest growth turbidity of OD = 1.010 while Penicillium from petrol-contaminated soil showed the highest growth turbidity of OD = 0.848. All the fungal isolates showed low ability to degrade engine oil. It was concluded that Cladosporium and Penicillium were the best microorganisms for the degradation of diesel and petrol respectively.
Keywords: Bioremediation potential, isolated fungal species, petroleum products, environmental impact, contaminated soil.