Of the known 92 potential hydrocarbon-utilizing bacteria and fungi isolated from crude oil polluted soil and water samples, only one soil bacterial isolate (SB17), identified as Bacillus subtilis, was found to efficiently degrade 72.23% of the Bonny light crude oil sample after 25 days of incubation, and thus was used for further investigations. Biodegradability of the major components of Bonny light crude oil was determined by column chromatographic analysis, and asphaltene, saturated hydrocarbon fractions, aromatic fraction and the nitrogen sulphur oxygen (NSO) containing fractions were found to be the major components. The chromatographic analysis after 25 days of incubation at 28oC also revealed that during the degradation of Bonny light crude oil, there was a continuous decrease of the saturated fraction and a relative increase of the aromatic and NSO fractions. These results suggest that Bacillus subtilis is a good candidate for microbial seeding of Bonny light crude oil polluted terrestrial environment.
Key words: Biodegradability, Bacillus subtilis, Bonny light crude oil, saturated hydrocarbon fractions, aromatic and NSOfractions.
(Global Journal of Pure and Applied Sciences: 2002 8(2): 215-222)