Isolation and Identification of Indigenous Bacteria for the Degradation of Polycyclic Aromatic Hydrocarbons Found in Refinery Wastewater

Polycyclic aromatic hydrocarbon (PAH) degrading bacteria were screened and isolated from contaminated soil taken from Tema Oil Refinery wastewater effluent channels. Refinery wastewater was found to contain a low amount of inhibitory heavy metals but the presence PAHs were detected and identified. The PAH-degrading bacteria isolated and identified were Pseudomonas stutzeri. Acinetobacter junii, Pseudomonas putida and Stetonotrophomonas nititireducens. All four bacteria showed high tolerance to a PAH combination of Naphthalene and Anthracene (1:1) of concentration as high as 5mg/ml. The identification of S. nititreducens as an indigenous bacterium is very significant since it is one of the very few bacteria known to be able to degrade high molecular weight PAHs.