Isolation, screening, and characterization of hydrocarbon-degrading bacterial strains from soil contaminated with engine oil in Kut city

Engine oil contamination is one of the foremost environmental problems caused by diverse human activities. Samples were collected from old garages and auto workshops and placed on a selective medium (Bushnell Haas mineral salt agar), with 1 % engine oil as the growth substrate. Thirty-one isolates from engine oil degraders were identified in eleven samples. Among these isolates, the samples (O9) 68 % and (O10) 64 % showed the highest degradation ability. Based on optical density measurement, biochemical testing, and molecular identification of the local isolate (O9); demonstrated that bacteria isolate (O9) belonging to Pseudomonas puttida, showed the highest biodegradation.