BIODEGRADATION OF SELECTED PETROLEUM PRODUCTS BY SOME BACTERIA ASSOCIATED WITH COWDUNG AND POULTY DROPPINGS.

Abstract

Bacteria associated with cow dungs and poultry droppings obtained from Teaching and Research Farm of Federal University of Technology Akure (FUTA), were isolated and assessed for the ability to degrade some petroleum products: petrol, kerosene, diesel, engine oil and transmission fluid. A total of ten isolates were obtained from the cow dungs and chicken droppings. The bacterial isolates were identified as Staphylococcus aureus, Bacillus pumilus, Enterobacter aerogene, Bacillus subtilis, Proteus vulgaris, Micrococcus letus, Escherichia coli, Bacillus subtilis, Proteus mirabilis and Salmonella typhimurium. Among the isolates, Bacillus pumilus and Proteus mirabilis showed ability to degrade petroleum products. Genetic analysis by 16S rRNA sequencing revealed that B. pumilus and P. mirabilis had sequence alignment of 99% and 100% respectively. Degradation of the petroleum products by the bacteria was carried out using turbidometry and gravimetric analysis. Diesel product was found to be most degraded of all the petroleum products. The gravimetric analysis, after the incubation period, revealed that B. pumilus and P. mirabilis had highest residual oil (highest degradation) of 0.062ml and 0.051ml for diesel respectively. Catechol 2,3-dioxygenase was found to be present in the organisms genes. Both bacteria could be employed in remediating spills of petroleum products especially diesel spills.