Search results
Results from the WOW.Com Content Network
The terms aerobic respiration, anaerobic respiration and fermentation (substrate-level phosphorylation) do not refer to primary nutritional groups, but simply reflect the different use of possible electron acceptors in particular organisms, such as O 2 in aerobic respiration, or nitrate (NO − 3), sulfate (SO 2−
Anaerobic digesters can also be fed with purpose-grown energy crops, such as maize. [8] Anaerobic digestion is widely used as a source of renewable energy. The process produces a biogas, consisting of methane, carbon dioxide, and traces of other 'contaminant' gases. [1]
An acetogen is a microorganism that generates acetate (CH 3 COO −) as an end product of anaerobic respiration or fermentation.However, this term is usually employed in a narrower sense only to those bacteria and archaea that perform anaerobic respiration and carbon fixation simultaneously through the reductive acetyl coenzyme A pathway (also known as the Wood-Ljungdahl pathway).
This definition distinguishes fermentation from aerobic respiration, where oxygen is the acceptor and types of anaerobic respiration, where an inorganic species is the acceptor. [citation needed] Fermentation had been defined differently in the past. In 1876, Louis Pasteur described it as "la vie sans air" (life without air). [7]
Anaerobic digestion is a complex biochemical process of biologically mediated reactions by a consortium of microorganisms to convert organic compounds into methane and carbon dioxide. It is a stabilization process that reduces odor, pathogens, and waste volume.
Numerous fermentation pathways exist such as lactic acid fermentation, mixed acid fermentation, 2-3 butanediol fermentation where organic compounds are reduced to organic acids and alcohol. [8] [4] The energy yield of anaerobic respiration and fermentation (i.e. the number of ATP molecules generated) is less than in aerobic respiration. [8]
In both aerobic and anaerobic systems the growing and reproducing microorganisms within them require a source of elemental oxygen to survive. [1] In an anaerobic system there is an absence of gaseous oxygen. In an anaerobic digester, gaseous oxygen is prevented from entering the system through physical containment in sealed tanks.
It is an anaerobic fermentation reaction that occurs in some bacteria and animal cells, such as muscle cells. [1] [2] [3] [page needed] If oxygen is present in the cell, many organisms will bypass fermentation and undergo cellular respiration; however, facultative anaerobic organisms will both ferment and undergo respiration in the presence of ...