Biodegradation of phenanthrene by a bacterial consortium enriched from Sercina oilfield

The phenanthrene (PHE) degradation by a halotolerant bacterial consortium enriched from production water of Sercina oilfield in Tunisia was investigated. The consortium PHMM utilized PHE (200 mg/L), as a sole carbon source, in the presence of a wide range of NaCl concentrations, from 1 to 5% (w/v). The maximum growth rate was obtained at 500 mg/L of PHE. A PHE metabolism was assayed by using FTIR, UV and GC–MS analyses. Results revealed that the consortium PHMM metabolized PHE via protochatechuate pathway since intermediates such as naphthalenol and phthalic acid were detected. Phylogenetic analysis showed that the adapted consortium PHMM was composed by two dominant bacterial strains, identified as Pseudomonas sp. (strain PH1) and Staphylococcus sp. (strain PH2). All the results indicated that the microorganisms from the Tunisian oilfield have a promising application in bioremediation of petrochemical contaminated environments and could be potentially useful for the study of PAHs biodegradation.