Characterization of a biodegrading bacterium, Bacillus subtilis, isolated from oil-contaminated soil

摘要

Crude oil and its derivatives because of different events and accidents may cause pollution to the environment. A biological treatment is a novel technique that uses microorganisms to remove or neutralize pollutants from a contaminated site. Oil-contaminated soils were sampled, after isolating of soil bacteria, using quantitative and qualitative screening, biosurfactant-producing bacteria were identified and environmental factors on the growth of bacteria and biosurfactant were investigated. In this study, the Bacillus subtilis was identified as the best biosurfactant-producing strain which has the ability to grow in environments with high salinity and temperature and pH > 5. The produced biosurfactant from B. subtilis is stable to changes in temperature and salt concentration and pH (in the range of 5-12).The B. subtilis also showed that they are able to biodegrade aliphatic alkanes. The B. subtilis has necessary potential for bioremediation of oil pollution in the environment.