Abstract
Screening of hydrocarbon degrading microorganisms from oil contaminated soil was studied and the samples were obtained from three Mechanical Workshops in Awka, Anambra State. The microorganisms were isolated using the pour plate method by selective enrichment technique. All samples were cultured in solid media with crude oil as a sole carbon and energy source to isolate hydrocarbon utilizers from the sample collected from different mechanic workshop. The isolate were identified on the basis of their colonial and morphological characteristics. Bacterial strains capable of degrading hydrocarbons belonging to the genera Bacillus spp, Micrococcus spp ,Corynebacterium spp and Pseudomonas spp; as well as five genera of fungi, Penicillin spp, Aspergillus spp, Rhizopus spp, Saccharomyces spp and Fusarium spp were isolated and identified. The colony forming unit per ml ranges from 0.22x 107 cfu/ml and 2.83 x 107 cfu/ml for the total heterogenous bacteria and 0.33x107 cfu/ml and 3 x 107 cfu/ml. The ability of the organism to survive is associated with the ability of the organism to use the crude oil as the sole carbon source. Some organism isolated from the total heterogenous bacteria and fungi were not able to grow in the media with the crude oil. These include bacteria genera Aeromonas and Staphylococcus and the fungi genera Cladosporium, Mucor, Geotrichium and Trichophyton. Some factors were seen that can affect the growth of these microorganisms, which include, temperature, nutrients and oxygen. The importance of these isolates for the bioremediation of oil polluted soil including the aerobic degradation of hydrocarbon and anaerobic degradation of hydrocarbon which is of great importance for control of hydrocarbon pollution in Nigeria was ascertained.