Background and purpose: Soil pollution to hydrocarbons in oil field zones in southern Iran and areas close to oil and gas transportation pipe lines is a major environmental problem. The current study aimed at determining the efficiency of bioremediation of n-Hexadecane contaminated soil as a model contaminant.

Materials and methods: Aged hydrocarbon contaminated soils were used as the origin of bacteria isolation. Isolation of n-Hexadecane degrading bacteria was carried out through enrichment in mineral salt medium and incubation in 31 ^oC in shaker incubator at 150 rpm by repetitive cultures during 6 consecutive refreshing. Finally, two pure strains were isolated and identified by PCR. Bioremediation of initial n-Hexadecane concentrations of 500, 1000 and 5000 mg/kg was investigated in eight weeks.

Results: Two Pseudomonas aeruginosa strains capable of n-Hexadecane biodegradation were isolated. The removal efficiencies at the end of day 56 for n-Hexadecane initial concentrations of 500, 1000 and 5000 mg/kg were 93.6%, 87.5%, and 69.62%, respectively.

Conclusion: Isolated Pseudomonas aeruginosa bacteria demonstrated high n-Hexadecane biodegradation potential in soil and also biosurfactant production, therefore, they could be used for bioremediation of hydrocarbon contaminated soils.