Crude oil biodegradation potential by mixed consortia of Pseudomonas Lurida and Bacillus Endophyticus

Abstract

Crude oil contamination poses significant environmental challenges due to the persistence and toxicity of its hydrocarbon components. This study evaluated the biodegradation potential of a mixed bacterial consortium comprising Pseudomonas lurida (DSM 15835) and Bacillus endophyticus (DSM 13796) using gas chromatography–mass spectrometry (GC–MS). Sterile sediment microcosms amended with 10% Bonny light crude oil were inoculated with approximately 5 × 10⁷ CFU of the consortium and monitored over five weeks. GC–MS analysis revealed substantial degradation of hydrocarbons ranging from C7 to C44, with marked reductions in peak abundance and the emergence of intermediate metabolites such as octane derivatives and alcohols. The consortium demonstrated enhanced biodegradation efficiency compared to single strains, indicating synergistic interactions. Growth curve analysis showed rapid exponential growth followed by an early stationary phase, suggesting efficient utilization of readily degradable hydrocarbons. The findings highlight the effectiveness of mixed microbial consortia in the bioremediation of petroleum-contaminated environments.