BIOREMEDIATION ACTIVITIES OF Pseudomonas putida AND Staphylococcus aureus ON SOIL CONTAMINATED WITH SPENT MOTOR ENGINE OIL IN ABAKPA-NIKE, ENUGU STATE NIGERIA

Biodegradation by natural population of microorganisms represents one of the cheap primary mechanisms by which petroleum and other hydrocarbon pollutants can be removed from the environment. The effectiveness of Pseudomonas putida and Staphylococcus auerus in remediation of soil contaminated with spent engine oil was investigated using standard methods. The result indicates significant variation in bacteria count between spent engine oil contaminated soil and control soil in 3rd to 6th week of bioremediation (p˂0.05). pH of control soil was significantly (P˂0.05) different from bio-remediated soil in the 1st, 4th, 5th and 7th week of bioremediation. Percentage organic matter content of control soil also differed significantly from bio-remediated soil in the 1st, 2nd, 3rd, 6th and 7th week of the experiment while the organic matter content of both samples did not show any significant difference in the 4th and 5th week (P˂0.05). There was no statistically significant difference between concentrations of Pb, Cu, and Zn in bio-remediated soil when compared with control soil (P˂0.05). Similarly total organic carbon in bio-remediated soil was not significantly different from the control soil (p=0.001). Pseudomonas putida and Staphylococcus aureus are effective in the clean-up of spent engine oil contaminated soil.