[01] Okafor Ugochukwu Chukwuma, Department of Applied Microbiology and Brewing, Faculty of Biosciences, Nnamdi Azikiwe University, Awka, Nigeria. [02] Nwose Onyeka Divine, Department of Applied Microbiology and Brewing, Faculty of Biosciences, Nnamdi Azikiwe University, Awka, Nigeria.

The hydrocarbon utilizing potential of microorganisms from spent engine oil-polluted soils was evaluated. Samples were collected from spent engine oil-polluted soils from three mechanic workshops at Ifite, Arroma and Kwata in Awka metropolis, Anambra state Nigeria. The total heterotrophic Indigenous bacterial count was evaluated and oil polluted soil sample obtained from mechanic workshop in Arroma had the highest count with a colony count of 3.5×10⁶cfu/g; soils obtained from Ifite and Kwata mechanic workshop had colony counts of 3.0×10⁶cfu/g and 2.5×10⁶cfu/g respectively. The Total Fungal count was also evaluated and soil samples from Kwata mechanic workshop showed the highest count with 3.9×10⁵cfu/g; colony counts of soils obtained from Ifite and Arroma mechanic workshop were 2.0×10⁵cfu/g and 2.5×10⁵cfu/g respectively. The Hydrocarbonoclastic microbial count showed that soil samples from mechanic workshop in Arroma had the highest load of hydrocarbonoclastic bacteria with a colony count of 4.1×10⁵cfu/g while soil samples from mechanic workshop in Kwata had the highest load of hydrocarbonoclastic fungi with a colony count of 3.3×10⁵cfu/g. The morphological and biochemical characteristics of the Hydrocarbonoclastic organisms were examined and the following genera were identified and they include: Pseudomonas (25%), Bacillus (25%), Acinetobacter (12.5%), Staphylococcus (12.5%), Micrococcus (12.5%),) and Enterobacter (12.5%),); Aspergillus (33.3%), Rhizopus (16.6%), Fusarium (33.3%) and Penicillium (16.6%); Candida (66.7%) and Trichosporon (33.3%). This study showed that majority of the Indigenous organisms has the ability to utilize hydrocarbon as their sole carbon source hence are the major bioremediating agents in the sampling areas.

Spent Engine Oil, Biostimulation, Hydrocarbonoclastic Organisms, Soil, Awka

[01] Ulrici, W., Rehm, H. J., and Reed, G.(2000). Contaminant soil areas, different countries and contaminant monitoring of contaminants,” in Environmental Process II. Soil Decontamination Biotechnology. 11: 5–42. [02] Kvenvolden, K. A. and Cooper, C. K., (2003). Natural seepage of crude oil into the marine environment. Geo-Marine Letters. 23 (3-4): 140–146. [03] Holliger, C., Gaspard, S., Glod, G., Heijman, C., Schumacher, W., Schwarzenbach, R. P. and Vazquez, F.(1997). Contaminated environments in the subsurface and bioremediation: organic contaminants. FEMS Microbiology Reviews. 20 (3-4): 517–523. [04] Medina-Bellver, J. I., Marín, P., Delgado, A., Rodríguez-Sánchez, A., Reyes, E., Ramos, J. L., and Marqués, S. (2005). Evidence for in situ crude oil biodegradation after the Prestige oil spill. Environmental Microbiology. 7 (6): 773–779. [05] April, T. M., Foght, J. M. and Currah, R. S., (2000). Hydrocarbon-degrading filamentous fungi isolated from flare pit soils in northern and western Canada. Canadian Journal of Microbiology. 46 (1): 38–49. [06] Leahy, J. G. and Colwell, R. R. (1990). Microbial degradation of hydrocarbons in the environment. Microbiological Reviews. 54 (3): 305–315. [07] Atlas, R. M. and Bartha, R., (1998). Fundamentals and applications. Microbial Ecology, Benjamin/Cummings, San Francisco, Calif, USA. pp. 523–530. [08] Mearns, A. J. (2001). Cleaning oiled shores: putting bioremediation to the test. Spill Science and Technology Bulletin. 4 (4): 209–217. [09] Prince, R. C., (1993). Petroleum spill bioremediation in marine environments. Critical Reviews in Microbiology. 19 (4): 217–242. [10] Swannell, R. P. J., Lee, K. and Mcdonagh, M., (1996). Field evaluations of marine oil spill bioremediation. Microbiological Reviews. 60 (2): 342–365. [11] Venosa, A. D., Suidan, M. T., and Suidan, M. T. (1996). Bioremediation of an experimental oil spill on the shoreline of Delaware Bay. Environmental Science and Technology. 30 (5): 1764–1775. [12] Venosa, A. D., King, D. W. and Sorial, G. A. (2002). The baffled flask test for dispersant effectiveness: a round Robin evaluation of reproducibility and repeatability. Spill Science and Technology Bulletin. 7 (5-6): 299–308. [13] Van Beilen, J. B. and Funhoff, E. G (2007). Alkane hydroxylases involved in microbial alkane degradation. Applied Microbiology and Biotechnology. 74 (1): 13–21, 2007. [14] Youssef, N., Simpson, D. R., Duncan, K. E., McInerney, M. J., Folmsbee, M., Fincher, T., and Knapp, R. M., (2007). In situ biosurfactant production by Bacillus strains injected into a limestone petroleum reservoir. Journal of Applied and Environmental Microbiology. 73 (4): 1239–1247. [15] Obayori, O. S., Ilori, M. O., Adebusoye, S. A., Oyetibo, G. O., Omotayo, A. E., and Amund, O. O., (2009). Degradation of hydrocarbons and biosurfactant production by Pseudomonas sp. strain LP1. World Journal of Microbiology and Biotechnology. 25 (9): 1615–1623. [16] Muthusamy, K., Gopalakrishnan, Ravi, S. T. K and Sivachidambaram, P., (2008). Biosurfactants: properties, commercial production and application. Current Science. 94 (6): 736–747. [17] Mahmound, A., Aziza, Y., Abdeltif, A. and Rachida, M. (2008). Biosurfactant production by Bacillus strain injected in the petroleum reservoirs. Journal of Industrial Microbiology & Biotechnology. 35 (2): 1303–1306.