Biodegradation of complex hydrocarbons in spent engine oil by novel bacterial consortium isolated from deep sea sediment

• Hydrocarbon degrading bacteria was isolated from deep sea sediment (2100 m).
• Degradation of oil was confirmed by FTIR and GC–MS analyses.
• Possible application in bioremediation of oil contaminated marine environments.

Complex hydrocarbon and aromatic compounds degrading marine bacterial strains were isolated from deep sea sediment after enrichment on spent engine (SE) oil. Phenotypic characterization and phylogenetic analysis of 16S rRNA gene sequences showed the isolates were related to members of the Pseudoalteromonas sp., Ruegeria sp., Exiguobacterium sp. and Acinetobacter sp. Biodegradation using 1% (v/v) SE oil with individual and mixed strains showed the efficacy of SE oil utilization within a short retention time. The addition of non-ionic surfactant 0.05% (v/v) Tween 80 as emulsifying agent enhanced the solubility of hydrocarbons and renders them more accessible for biodegradation. The degradation of several compounds and the metabolites formed during the microbial oxidation process were confirmed by Fourier transform infrared spectroscopy and Gas chromatography–mass spectrometry analyses. The potential of this consortium to biodegrade SE oil with and without emulsifying agent provides possible application in bioremediation of oil contaminated marine environment.

Biodegradation of spent engine (SE) oil by deep sea bacterial consortium.Figure optionsDownload as PowerPoint slide