Paper Title
Comparative Biodegredation of PAHs in used Engine Oil between Pseudomonas Aeruginosa and Bacillus Licheniformis Isolated from Contaminated Soil of Mechanic Workshop in Sokoto Metropolis

The ability of used engine oil degrading Pseudomonas Aeruginosa and Bacillus Licheniformiswas compared in this study. The bacteria were isolated from the contaminated soil of mechanic work shop in sokoto state of Nigeria, they were characterised base on their morphological, biochemical and genetic characteristic. They were subjected to biodegradation of PAHs in used engine oil as their soul carbon source for the period of three months. Different standard of colony forming unit (cfu) was used at 0.5, 1.0, 2.0, 3.0 and 4.0. The result of gravimetric analysis shows that in all the different cfu of Pseudomonas Aeruginosa, more than 50% of the oil was degraded with highest seen at 3.0 cfu which is 55.74%. while Bacillus Licheniformiswas only able to degrade 40% of the oil in all the cfu with highest seen at 3.0 cfu as well with 48.87%. The result of the gc-ms shows that only at 1.0 cfu of P. Aeruginosathat there was a significant difference in the concentration of pahs metabolite when compared both within the group and outside the group at p- value less than 0.05, this confirm that at a medium concentration P. Aeruginosacolony forming unit, the bacteria can degrade pahs in used engine oil to a significant level. Therefore it can be employed in the process of bioremediation of pahs contaminated soil in the environment. Keyword - Bioremediation, Contaminated Soil, Polycyclic Aromatic Hydrocarbon.