Comparison of In vitro Study of Aspergillus niger and Pseudomonas aeruginosa Biodegradation of Spent Lubricating Oil

Comparison of biodegradation of spent lubricating oil by Aspergillus niger and Pseudomonas aeruginosa was studied for 16 days. pH, turbidity, nitrate, phosphorus and Gas Chromatographic -Mass Spectrophometry (GC-MS) analyses of the media were carried out. The results showed lower pH and phosphorus levels in A. niger medium compared to Pseudomonas aeruginosa medium and the control while nitrate was higher in Pseudomonas aeruginosa compared to A. niger. The GC-MS revealed that more compounds were degraded by A. niger than Pseudomonas aeruginosa after 16 days. Azulene and benzene were not degraded by both organisms. This study suggests that A. niger grows and metabolize compounds in spent lubricating oil better than Pseudomonas aeruginosa and that neither of the two organisms had the competent enzymes to degrade azulene and benzene in two weeks.