Clostridium acetobutylicum

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Clostridium acetobutylicum is a commercially valuable bacterium, included in the genus Clostridium. It is sometimes called the "Weizmann Organism", after Chaim Weizmann, who in 1916 helped discover how C. acetobutylicum culture could be used to produce acetone, butanol and ethanol from starch using the A.B.E. ( Acetone, Butanol,Ethanol) process to enable industrial purposes such as gunpowder and TNT production. The A.B.E. process was an industry standard until the 1950's when low oil costs drove more efficient processes based on hydrocarbon cracking and petroleum distillation techniques. C. acetobutylicum also produces acetic acid (vinegar), butyric acid (a vomitous smelling substance), carbon dioxide and hydrogen.

Anaerobic fermentation using C. acetobutylicum recently regained marked interest for use in vehicle fuel production as a gasoline and diesel fuel replacement. This is because butanol as produced by a fibrous bed bioreactor utilizing recent biotechnology co-developed by Environmental Energy Inc. and The Ohio State University produces the alcohol butanol as its primary output. The patented process using C. tyrobutyricum produces little acetone or ethanol, instead producing butyric acid and hydrogen which is then pumped into another fibrous bed bioreactor where C. acetobutylicum converted the butyric acid into butanol, thus optimizing butanol production. Essentially, the new process obviates the A.B.E. process, making butanol production competitive with other biofuels economically and energetically.

100% Butanol can be utilized in normally gasoline-powered car without any modifications, producing similar mileage performace to gasoline and produces less Nox pollutants. If produced from a biomass source, there is no net carbon dioxide production.

Unlike yeast, which can only digest sugar into alcohol and carbon dioxide, C. acetobutylicum and many other Clostridium can digest whey, sugar, starch, lignin, cellulose fiber and other biomass directly into butanol, propionic acid, ether, and glycerin. Apart from the need for temperature control, the ABE synthesis process is relatively simple. The products are formed in layers that are easy to separate.

Biobutanol supporters claim significant advantages over other biofuels used to fuel internal combustion-based vehicles and other liquid-fueled processes.

butanol has a higher octane fuel value than gasoline with increased low-end torque. A V-8 engine has been tested on a 10,000 mile US tour supporting a US Department of Energy grant in 2005. The results of the butanol auto fuel demonstration was presented to the U.S. Department of Energy National Renewable Energy Laboratory's [Clean Energy Forum] in San Francisco in November 7, 2005.
butanol can be produced for less than fossil based vehicle fuels.
butanol reduces vehicular emissions.
butanol does not readily adsorb moisture (it is not hygroscopic), so is less affected by changes in the weather, unlike the combustion of pure ethanol, which requires engine and fuel system modifications. Biodiesel gels at low temperatures, which requires fuel system modifications in cold climates, or blending with other fossil fuels such as kerosene or #1 diesel.
butanol does not attack materials commonly used in vehicular internal combustion engines.
biobutanol can also be used in the industrial paint and solvent industry to replace fossil butanol.

External links

[www.pubmedcentral.gov] Genome Sequence and Comparative Analysis of the Solvent-Producing Bacterium Clostridium acetobutylicum (pdf)

[link] Amino acid transport by membrane vesicles of an obligate anaerobic bacterium, Clostridium acetobutylicum. (pdf)

[link] Structure of an endo-beta-1,4-glucanase gene from Clostridium acetobutylicum P262 showing homology with endoglucanase genes from Bacillus spp.(pdf)

[link] Effects of butanol on Clostridium acetobutylicum. (pdf)

[www.findarticles.com] Bacteria speeds drug to tumors - use of Clostridium acetobutylicum enzyme to activate cancer drug CB 1954

[EPA Clostridium acetobutylicum Final Risk Assessment]

[Carolina Bio Supply Living Culture Order Page]

[Genetic Engineering of Clostridium acetobutylicum for Enhanced Production of Hydrogen Gas]: Penn State University.

Clostridium acetobutylicum

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See also