Petroleum Hydrocarbons and Organic Chemicals in Ground Water: Prevention, Detection, and Remediation® Conference

Monday, November 3, 2008 : 4:00 p.m.

Biodegradation of Gasoline Under Microaerophilic Conditions

Karim Acuna-Askar, Sc.D., Jhonatan N. Martinez-Ochoa, Rolando Tijerina-Menchaca, M.D., Maria T. Garza-Gonzalez, Sc.D., Humberto Rodriguez-Fuentes, Sc.D., Universidad Autonoma de Nuevo Leon, German Buitron-Mendez, Universidad Nacional Autonoma de Mexico Instituto and Benjamin Chavez-Gomez, Sc.D., Instituto Mexicano

The objective of this research was to evaluate the biodegradation of gasoline in a continuous-flow biofilm reactor under oxygen limiting conditions at three oxidation reduction potential (ORP) levels: -150, +50 and +150 mv, at a hydraulic retention time (HRT) of 12 hours.  Alluvial stone with a density of 2.45 g/cm3 was used as the microbial support to keep the microbial populations growing to form a biofilm.  The initial total gasoline concentration was 30 mg/L, and biodegradation percentages were quantified as total gasoline components (TGC) and as non-MTBE gasoline components (NGC, i.e., total gasoline minus MTBE).  TGC and NGC biodegradation percentages for each ORP level recorded 35.5% and 78.8%, at -150 mv; 27.6% and 94.2% at +50 mv; 54.3% and 96.3%, at +150 mv, respectively.  TGC partial biodegradation was attributed to MTBE recalcitrance.  NGC biodegradation rates, which ranged 0.145-0.258 h-1, were higher than the TGC biodegradation rates, which ranged 0.0040-0.121 h-1 for the three ORP levels tested. 

Karim Acuna-Askar, Sc.D. Professor and Head, Environmental Bioremediation Research Laboratory, Department of Microbiology, School of Medicine, Autonomous University of Nuevo Leon. Received Doctor of Science degree in Environmental Health Sciences, Water Quality Program from Tulane University, New Orleans, LA, in 1998. Master of Science degree in Analytic Chemistry, Autonomous University of Nuevo Leon, in 1991. Bachelor of Science in Chemistry, Monterrey Institute of Technology in 1986.

Jhonatan N. Martinez-Ochoa Student, Bachelor of Science in Chemistry, Autonomous University of Nuevo Leon. Research Assistant in the Environmental Bioremediation Research Laboratory, Department of Microbiology, School of Medicine, Autonomous University of Nuevo Leon.

Rolando Tijerina-Menchaca, M.D. Professor and Chairman, Department of Microbiology. Received Doctor of Medicine degree from University of Hamburg, Germany in 1983. Bachelor degree in Medicine, Autonomous University of Nuevo Leon, in 1975.

Maria T. Garza-Gonzalez, Sc.D. Professor and Associate Dean for Graduate Studies, School of Chemical Sciences, Autonomous University of Nuevo Leon. Received Doctor of Science degree in Microbiology from University of La Habana, Cuba in 2005. Master of Science degree in Industrial Microbiology, Autonomous University of Nuevo Leon, 1993. Bachelor of Science degree in Chemistry, Autonomous University of Nuevo Leon in 1974.

Humberto Rodriguez-Fuentes, Sc.D., Universidad Autonoma de Nuevo Leon Professor, Department of Agricultural Engineering, School of Agronomy, Autonomous University of Nuevo Leon. Received Doctor of Science degree in Agricultural Engineering from Autonomous University of Nuevo Leon in 1997. Master of Science in Agricultural Engineering, University of Costa Rica CATIE Research Center. Bachelor of Science degree in Agronomy, Autonomous University of Nuevo Leon, 1979.

German Buitron-Mendez, Universidad Nacional Autonoma de Mexico Instituto Professor and Head, Laboratory of Advanced Research on Water Processes, Institute of Engineering, National Autonomous University of Mexico. Received Doctor of Science degree in Chemical Engineering, Water Treatment program, from the National Institute of Applied Science, Toulouse, France in 1993. Master of Science degree in Chemical Engineering, Water Treatment program, National Institute of Applied Science, Toulouse, France, 1990. Bachelor of Science degree in Chemical Engineering from the National Autonomous University of Mexico in1987.

Benjamin Chavez-Gomez, Sc.D., Instituto Mexicano Researcher, Mexican Petroleum Institute. Doctor of Science and Master of Science degrees in Biotechnology from the Advanced Research Center of the National Polytechnic Institute of Mexico. Bachelor of Science degree in Biochemical Engineering from the National School of Biological Sciences of the National Polytechnic Institute of Mexico. Current projects include bioremediation of soil and groundwater contaminated with hydrocarbons.


Petroleum Hydrocarbons and Organic Chemicals in Ground Water: Prevention, Detection, and Remediation® Conference