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Electron Donor


Electron Donor - "The compound that donates electrons (and therefore is oxidized). In bioremediation the organic contaminant often serves as an electron donor." - National Research Council, 1993

Electron Donor - "A chemical entity that donates electrons to another compound. It is a reducing agent that, by virtue of its donating electrons, is itself oxidized in the process." - U.S. Environmental Protection Agency, 2012

Electron Donor - "Suitable electron donors (such as organic compounds) together with electron acceptors (such as O2, nitrate, ferric iron, sulfate, CO2, or certain types of simple organic compounds) are required for the generation of energy. N [nitrogen], P [phosphorus], and S [sulfur] sources may be organic or inorganic, with some microorganisms able to use either while others are more restricted." - Pankow and Cherry, 1996

Electron Donor - "Redox reactions involve the transfer of electrons from a donor molecule to an acceptor molecule. The electron donor (D) loses n electrons and is oxidized: D=Dn++ne-. The electron acceptor (A) gains the n electrons and is reduced: A+ne-=An-. The term redox is short-hand for reduction and oxidation. It underscores that reduction of an acceptor and oxidation of a donor always occur together so that all electrons leaving the donor are taken up by the acceptor: D+A=Dn++An-." - National Reseach Council, 1993

Text in brackets ("[text]") are added by the editor.

Related Definitions


Electron Acceptor


Aerobic Biodegradation


Anaerobic Biodegradation



Natural Attenuation

USGS Information on Biodegradation

Related Headlines

Other Information on Biodegradation


National Research Council, 1993, In situ bioremediation--When does it work?: Washington, D.C., National Academies Press, 224 p.

Pankow, J.F., and Cherry, J.A., 1996, Dense chlorinated solvents and other DNAPLs in groundwater--History, behavior, and remediation: Portland, Oregon, Waterloo Press, 522 p.

U.S. Environmental Protection Agency, 2012, Glossary of technical terms: U.S. Environmental Protection Agency, access date June 2, 2014.



Disclaimer: The definitions on this page are provided for information purposes only, and do not indicate endorment by the U.S. Geological Survey.

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