Bioremediation
Introduction
Bioremediation refers to the use of microorganisms to degrade contaminants that pose environmental, and especially human risks. It has become an accepted remedy to clean-ups due to its safety and convenience. The process relies on the microorganisms that are natural to the soil, and also allows scientists to solve the problem right at the site of contamination. [1]
New applications of bioremediation continue to be developed to degrade hazardous chemicals, although there are similarities between approaches. Characteristics common to bioremediation processes include:
1)Many different microbes acting in parallel or sequence often complete the degradation process 2)Ability to address many different pollutants 3)Applied to very different environmental conditions
Bioremediation Applications
Examples
Degradation Pathways
Advantages/Possibilities
Monitoring
Key Microorganisms
Pseudomonas putida is a gram-negative soil bacterium that is involved in the bioremediation of toulene, a component of paint thinner. It is also capable of degrading naphthalene, a product of petroleum refining, in contaminated soils. [2]
Industrial bioremediation is used to clean up wastewater. Most treatment systems rely on microbial activity to remove unwanted compounds from the wastewater, for example fixed nitrogen compounds (i.e. ammonia). The reduction of ammonia to dinitrogen gas involves two different microbes. First, Nitrosomonas europaea reduces ammonia to nitrite. Then, Paracoccus denitrificans reduces nitrite to dinitrogen gas. Therefore, the nitrogen pollution in the wastewater is eliminated as the gas escapes to the atmosphere. Denitrification is the process of consuming fixed forms of nitrogen as the electron acceptor in anaerobic conditions and reducing it to dinitrogen gas [2].
References
1. United States Environmental Protection Agency, "A Citizen's Guide to Bioremediation" 2001.
2. Nitrification and Denitrification Wastewater Treatment. No. 5536407. 16 July 1996. <http://www.google.com/patents?id=F9UZAAAAEBAJ>
Edited by student of Kate Scow