Abstract
Petroleum crude oil biodegrading fungi were isolated from Treculia africana seeds in the presence and absence of petroleum fumes. An assessment of the relative ability of each fungus to biodegrade petroleum crude oil, kerosene, diesel, unspent engine oil, spent engine oil and extracted oil from T. africana seeds on minimal salt solution was investigated using changes in optical density read on a spectrophotometer and gas chromatographic analyses. Ten fungi were isolated from T. africana seeds in the presence and absence of petroleum fumes. These included one species each of Mucor, Paecilomyces, Rhizopus and Syncephalastrum, four species of Aspergillus and two species of Penicillium. It was evident that the fungi used in this research work were capable of biodegrading the petroleum and extracted T. africana seed oil hydrocarbon, though at different rates. Rhizopus had the highest degrading ability in kerosene, unspent engine oil, crude oil and the extracted oil from the seed, while Penicillium pinophyllum had the lowest ability to degrade the oil. The gas chromatogram (GC) showed that Paecilomyces biodegraded the hydrocarbons in the crude oil compared to the control (crude without fungi) using up some carbon atoms (C12-C24) after the 40 days of incubation, suggesting n-alkane biodegradation. Also the GC analysis of the seed oil of T. africana, after 40 days of incubation, showed a reduction in the seed oil hydrocarbons, removing C10- C15.
Key words: Hydrocarbon utilization, Treculia Africana, seeds, petroleum crude oil, fungi.
