The consequences of oil pollution to the environment and human health as a result of exploration activities, transportation and usage of petroleum compounds, has become a serious challenge to environmental scientists. This study evaluates the potential of using Bacillus subtilis in biodegradation of petroleum compounds. Ten Bacillus strains from non-petroleum contaminated sites were identified on the basis of microscopy and biochemical tests. The ability of B. subtilis S4 to degrade crude oil was tested by growing in crude oil contaminated soil. The biodegradation products were analysed by gas chromatography-mass spectroscopy (GCMS). The GCMS indicated that some high molecular mass components of the crude oil were broken down to lower molecular mass compounds. Octacosane (MM = 394) disappeared after biodegradation with Bacillus S4. It is suggested that B. subtilis has the potential to degrade crude oil.

Keywords: Biodegradation, Bacillus, crude oil, gas chromatography-mass spectroscopy.