Crude oil biodegradation using bacterial isolates from river Nile state under aerobic conditions

Abstract

One-hundred and twenty five strains of petroleum degrading bacteria were isolated from hydrocarbons contaminated soil and wastewater sink at Aljayli refinery in River Nile State, Sudan. Column Gas Chromatography used to detect the residual oil after incubation of isolates in basal medium. The most potential isolates were tentatively identified as: Pseudomonas aeruginosa, P. putida, Serratia marcences, Cedeca davicae, Enterobacter cloacae, Yersinia enterocolytica and Citrobacter freundi. S. marcences exhibited the highest emulsification ability to crude oil, nC8 to nC16 was nearly completely disappeared followed by P. putida which was active in degradation nC8-nC15 (99%-96%) while nC35-nC37 completely degraded. P. aeruginosa represent approximately the same results except nC9 which recorded (84%). Citrobacter freundii, was the lowest isolate in degradation of nC8 and nC9 but high for nC10-nC13. It is realized that isolates were able to degrade n-alkane more than total petroleum hydrocarbons.