Assessment of possible biological removing of different concentration of crude oil by rhizospheral fungal strains in Tehran refinery area

The contamination of soil by crude oil is an important environmental problem. Bioremediation have gained more attention in recent years as a low-cost technique for pollutant removal. The aim of this research was to investigate the ability of rhizospheral fungal strains collected from plants grown in a petroleum-polluted soil using different concentrations of pollutant. In this research rhizospheral fungal strains were collected from the plants grown in the Tehran refinery area and cultured on the PDA media containing different concentrations (0-15%) of crude oil. Efficiency of removal for each isolated fungi was determined after one month. Results showed that، all fungi were able to remove petroleum at the concentrations of 1، 2، 4 and 6% (P≤0. 01). In addition all the fungi except Diplosporium sp. and Penicillium sp.، were able to decrease crude oil at the concentrations of 8، 10 and 15% (P≤0. 05). It was concluded that the studied fungi were able to remove the crude oil from the growth media. Since Aspergillus sp. was relatively more effective therefore this fungus has the highest bioremediation potency of petroleum polluted environments.