African Journal of
Microbiology Research

  • Abbreviation: Afr. J. Microbiol. Res.
  • Language: English
  • ISSN: 1996-0808
  • DOI: 10.5897/AJMR
  • Start Year: 2007
  • Published Articles: 5233

Full Length Research Paper

Biodegradation of mineral oil by bacterial strains isolated from contaminated soils

Abdel-Megeed A.1,2*, Islam I. Abou Elseoud3, Mostafa A.A.1, Al-Rahmah A.N.1, and Eifan S.A.1
1Department of Botany and Microbiology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Kingdom of Saudi Arabia. 2Department of Plant Protection, Faculty of Agriculture (Saba Basha), Alexandria University, Egypt. 3Department of Soil and Agriculture Chemistry, Faculty of Agriculture (Saba Basha), Alexandria University, Egypt.
Email: [email protected]

  •  Accepted: 24 September 2012
  •  Published: 06 November 2012


Potential mineral oil degrading bacterial isolates (Pseudomonas putida, Rhodococcus erythroplolis and Bacillus thermoleovorans) were studied from the contaminated soils.The bacterial populations of these polluted soils were 5.25 × 105, 1.76 × 106 and 5.11 × 105 CFU/ml with three different colony types of bacterial strains, respectively. Microbial population diversity studies were carried out by microbial enumeration, identification, and determination of growth responses of bacterial isolates in different concentrations of mineral oil sample. Phenotypic examination of the heterotrophic bacteria belonged mainly to the genus Pseudomonas, Rhodococcus and Bacillus. The mixed populations are capable of degrading mineral oil up to 120 ppm. Mineral oil biodegradation was fast by the mixed culture comparing to the biodegradation of each strain separately. Since the biological treatment can efficiently destroy the hydrocarbons and does not allow the contaminant to accumulate, it is considered to be a superior technology. This study revealed that the mixed bacterial consortium achieved maximum crude oil degradation at pH 7. Hence, it is suggested that the use of the aforementioned mixed bacterial consortium under optimized conditions will be an effective and eco-friendly technology for the degradation of hydrocarbons from BH crude oil.


Key words: Mineral oil, biodegradation, Pseudomonas putida, Rhodococcus erythroplolis,Bacillus thermoleovorans.