Bioremediation of Carcinogenic PAHs by Two Bacterial Strains

Removal of PAHs from the environment is important because of their potentially deleterious effect on human health. Among the methods were used for this purpose, biological methods which typically contain microbial processes are most innocuous and effective solution that due to transform pollutant to nontoxic or less toxic substances. The objectives of the present study are enrichment, isolation and identification of PAHs degrading bacteria from oil-contaminated soil by molecular detection methods. Eight indigenous bacteria were isolated from oil-contaminated soils by using the enrichment methods. Tow isolates with the highest optical density potentials in media with 11.8 mg.L-1 of 11 PAHs as the sole source of carbon were selected. They were identified as Bacillus licheniformis ATHE9 and Bacillus mojavensis ATHE11by subjected to polymerase chain reaction with 11SrDNA primer and biochemically characterized. The bacterium strain Bacillus licheniformis ATHE9 was isolated in this study removed Acenaphtylene, Acenaphtene and Indeno pyrene in 21, 91 and 91 hours, respectively. The Bacillus mojavensis ATHE11 could remove Naphthalene in 21 hours and Acenaphtene, Acenaphtylene, Benzo(ghi)prylene, Dibenzo(ah)anthracene and Indeno pyrene in 91 hours. The results of this study strongly indicate that some of the indigenous bacteria have the potential to remediate polycyclic aromatic hydrocarbons from oil-contaminated sites.

Keywords:

Bacterial identification , Gas chromatography , Indigenous bacteria , Pollution , Remediation