ABSTRACT

The introduction of petroleum hydrocarbons into a pristine environment immediately changes the nature of that environment. The introduced hydrocarbons kill or inhibit many microbial species, thereby altering the functionality of the microbial community and therefore the ecosystem. This study is aimed at isolating, characterizing and identifying Bacteria isolates from petroleum spilled soil. A total of 9 soil samples were collected within Umuahia and Umudike from two soil depths of O to I 5 cm and I 5 to 30 cm in both locations in a randomized manner. The samples were analyzed microbiologically and biochemically. The bacterial load of the spill contaminated area ranged from 1.12 x 10 8 cfu/g to 1.35 x 10 cfu/g while the outside immediate surrounding soil recorded bacterial load ranging from 8. 7 x 107 cfu/g to 1.02 x 10° cfu/g. The control soil had bacterial load ranging from 1.2 x 10 7 cfu/g to 1.7 x 107 cfu/g. The result of the percentage occurrence of bacteria showed that Baccilus specie had the predominant occurrence of 92.59% while Norcadia had the least occurrence of 22.2%. Bacillus species predominated, especially in the crude oil polluted soil. This may be due to the ability of the organisms to produce spores, which may shield them from the toxic effects of the hydrocarbons.