Biodegradation of naphthalene by Bordetella avium isolated from petroleum refinery wastewater in Egypt and its pathway

Wastewater and Sludge samples polluted with petroleum oil from Cairo Oil Refining Company (CORC), Mostorod, El-Qalyubiah, Cairo, Egypt. were used for isolation of indigenous bacterial communities. The isolation of bacterial strains followed four steps of adaptation and enrichment technique for selection of the most Naphthalene tolerant bacterial strains. Screening on four Naphthalene concentrations to determine the most potent strains having the abilities to use Naphthalene as a sole carbon and energy source have been conducted. The most potent bacterial isolates were MAM-P9, MAM-P14, MAM-P22, MAM-P25 and MAM-P26. The abilities of the five most potent bacterial isolates to grow on BSM amended with 4,5,6 and 7 mM Naphthalene have been determined by recording their growth (O.D) and secretion of extracellular protein after zero time (initial), 1,2,3,4,5,6,7,14 and 21 days spectrophotometrically. The degradation of Naph. have been determined quantitatively by High Performance Liquid Chromatography (HPLC) and qualitatively by GC/MS to determine the Intermediates resulted from degradation. The results revealed that isolate MAM-P22 was the best Naphthalene degrader. It degraded 95% of the highest concentration 7 mM. The best Naphthalene degrader bacterial Isolate MAM-22 was identified by 16S-rRNA showed a similarity of 98% to Bordetella avium strain with accession No. 041769.1. The results of GC/MS analysis revealed that Bordetella avium MAM-P22 degraded Naphthalene to give six intermediate compounds, These compounds were 1,2-Benzene dicarboxylic acid, Butyl-2,4-dimethyl-2-nitro-4-pentenoate, 1-Nonen-3-ol, Eicosane, Nonacosane.