The Biodegradation of Crude Oil by Bacillus subtilis Isolated from Contaminated Soil in Hot Weather Areas

Document Type : Original Research Paper


1 Department of Environmental Engineering, Khouzestan Science and Research Branch, Islamic Azad University,Ahvaz, Iran

2 Khouzestan Science and Research Branch, Islamic Azad University, Ahvaz, Iran

3 Department of Microbiology, Damghan Branch, Islamic Azad University, Damghan, Iran

4 Department of Environment, Roudehen Branch, Islamic Azad University, Roudehen, Iran

5 Department of Environment, Faculty of Marine Science and Technology, North Tehran Branch, Islamic Azad University, Tehran, Iran


Using Environmental-friendly methods in order to remove or reduce oil pollutants and their derivations in the environment are developing. In this study, the biodegrading ability of Bacillus Subtilis .sp which has been separated from oil-polluted soil was examined. It was revealed that it can reduce surface tension of growth Medium and produce Bio-Surfactant at 37 and 20 Degrees centigrade. Also, it has the ability to biodegrade oil hydrocarbons. A reduction in surface tension from 58 Nm/m to 31.2 Nm/m at different percentages of crude oil at 37 degrees centigrade is one of the important results.