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Potential Application of Anaerobic Extremophiles for Hydrogen ProductionDuring substrate fermentation many anaerobes produce the hydrogen as a waste product, which often regulates the growth of the cultures as an inhibitor. In nature the hydrogen is usually removed from the ecosystem due to its physical properties or by consumption of hydrogen by secondary anaerobes, which sometimes behave as competitors for electron donors as is seen in the classical example in anaerobic microbial communities via the interaction between methanogens and sulfate- or sulfur- reducers. It was demonstrated previously on mixed cultures of anaerobes at neutral pH that bacterial hydrogen production could provide an alternative energy source. But at neutral pH the original cultures can easily be contaminated by methanogens, a most unpleasant side effect of these conditions is the development of pathogenic bacteria. In both cases the rate of hydrogen production was dramatically decreased since some part of the hydrogen was transformed to methane, and the cultivation of human pathogens on a global scale is very dangerous. In our laboratory, experiments with obligately alkaliphilic bacteria that excrete hydrogen as the end metabolic product were performed at different temperature regimes. Mesophilic and moderately thermophilic bacterial cultures have been studied and compared for the most effective hydrogen production. For high-mineralized media with pH 9.5-10.0 not many methanogens are known to exist. Furthermore, the development of pathogenic contaminant microorganisms is virtually impossible: carbonate-saturated solutions are used as antiseptics in medicine. Therefore the cultivation of alkaliphilic hydrogen producing bacteria could be considered as most safe process for global Scale industry in future. Here we present experimental data on the rates of hydrogen productivity for mesophilic, alkaliphilic, obligately anaerobic bacterium Spirocheta americana ASpG1 and moderately thermophilic, alkaliphilic, facultative anaerobe Anoxybacillus pushchinoensis K1 and discuss the potential implications for alternative energy sources.
Document ID
20040112060
Acquisition Source
Marshall Space Flight Center
Document Type
Conference Paper
Authors
Pikuta, Elena V.
(National Space Science and Technology Center Huntsville, AL, United States)
Hoover, Richard B.
(National Space Science and Technology Center Huntsville, AL, United States)
Date Acquired
August 21, 2013
Publication Date
January 1, 2004
Publication Information
Publication: 49th Annual Meeting Proceedings: Insruments, Methods, and Missions for Astrobiology VIII
Volume: 5555
Subject Category
Energy Production And Conversion
Meeting Information
Meeting: International Society for Optical Science and Technology: Insruments, Methods, and Missions for Astrobiology VIII
Location: Denver, CO
Country: United States
Start Date: August 2, 2004
End Date: August 6, 2004
Sponsors: International Society for Optical Engineering
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

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