Occurrence of hydrocarbon-utilising bacteria in oil-polluted arid soils in Sudan

ABSTRACT

Aims@#This study aimed to isolate and identify hydrocarbon-utilising bacteria from oil- polluted sites and to develop a microbial consortium for use in pilot trial and commercial scale bioremediation treatment systems in the future.@*Methodology and results@#Ten hydrocarbon-utilising bacterial strains were isolated using enrichment culture technique from oil-polluted sites using crude oil as sole carbon source. The strains were tentatively identified on the basis of colony morphology, microscopic examination and biochemical characteristics. The growth of each strain was assessed by growing the bacteria in mineral salt medium amended with diesel oil as sole carbon source. The isolates exhibited differences in growth with the order of biomass production being Enterobacter sp. (OD620=1.283)> Bacillus subtilis subsp. subtilis (OD620=1.245) > Aerococcus sp. (OD620=1.100) > Bacillus firmus (OD620=0.970) > Corynebacterium sp. (OD620=0.886) > Bacillus lentus (OD620=0.743) > Micrococcus luteus (OD620=0.656) > Bacillus subtilis (OD620=0.367) > Bacillus cereus (OD620=0.110) > Kocuria flavus (OD620=0.065). @*Conclusion, significance and impact of study@#This study is a prerequisite for the design of future full-scale bioremediation treatment of oil-polluted sites using hydrocarbon-utilising bacteria. An efficient consortium was developed comprising the best three hydrocarbon-utilising strains, which include Enterobacter sp., Bacillus subtilis subsp. subtilis and Aerococcus sp. This efficient microbial consortium is suggested to be used in future to rehabilitate oil-polluted sites in Sudan.