Isolation of a Novel Bacterium Isolate Capable of Utilizing Crude Oil and Diesel Oil Spills as a Biological Bioremediation Agent.

Background: Contamination with crude oil and hydrocarbons has become a global threat. Such threats have urged us to invent solutions to deal with this dilemma. However, chemical treatment comes with limited benefits. The use of bioremediation proved to be the optimal approach to face this problem since it is cost-effective, time-conserving and may improve the quality of soil and increase its fertility.

Methods: Soil samples were collected from three sites with the highest degree of pollution in Iraq: Al-Latifia, Al-Begei, and Basra. These were the source of novel Streptomyces isolates that could degrade contaminants and be used as a source of nutrients. The isolation principle was the degradation of petroleum in these soils as a carbon source.

Results: The most efficient isolate was obtained from Basra soil, characterized by the highest degree of contamination. The bacterium grows on minimal medium with crude oil, diesel fuel, aromatic, and non-aromatic hydrocarbons as the only source of carbon and showed the ability to reduce a hydrocarbon mixture containing 23 analytes with C8-C40 and C13-C30 representing total crude hydrocarbons effectively and with a high mineralization capability reaching 84%. This isolate was found to produce biosurfactants and reduce surface tension significantly.

Conclusions: Using chemical treatment of crude oil contaminants, burying the contaminated areas, or sometimes flooding them with water to eliminate these contaminants may not be an effective solution. Thus, using nonpathogenic microorganisms, especially those indigenous to the soil, maybe the most effective solution to achieve this goal.