Crude oil hydrocarbon degradation efficiency of indigenous bacterial strains isolated from contaminated sites in Nigeria

The crude oil degradation potential of bacterial isolates from three contaminated sites in Nigeria were investigated. Seven bacterial isolates namely Pseudomonas aeruginosa strain W15, Pseudomonas aeruginosa strain N3R, Serratia marcescens strain N4, Providencia vermicola strain W8, Serratia marcescens strain W13, Pseudomonas aeruginosa strain W11 and Pseudomonas protegens strain P7 were isolated and identified using molecular methods. Isolates N4, N3 and W13 showed higher % total petroleum hydrocarbon (TPH) degradation of 79.26%, 78.96% and 78.69% respectively than W15, P7, W8 and W11 with % TPH degradation of 68.96%, 62.14%, 59.75% and 59.00% respectively. W13 showed the fastest degradation rate with 78.72% within the first 14 days of incubation; however, after the 14th day, there was no progressive change in % TPH. W11 showed degradation of wider range of hydrocarbon components originally in the crude oil as well as the complete degradation of most intermediates formed. The isolates showed good degradation potentials for bioremediation applications.