Acetone-butanol-ethanol fermentation

Grube, M. Gapes, J.R. 8t Schuster, K.C., Application of quantitative IR spectral analysis of bacterial cells to acetone-butanol-ethanol fermentation monitoring Anal. Chim. Acta 2002, 471, 127-133. 

We explored the influence of dilution rate and pH in continuous cultures of Clostridium acetobutylicum. A 200-mL fibrous bed bioreactor was used to produce high cell density and butyrate concentrations at pH 5.4 and 35°C. By feeding glucose and butyrate as a cosubstrate, the fermentation was maintained in the solventogenesis phase, and the optimal butanol productivity of 4.6 g/(L h) and a yield of 0.42 g/g were obtained at a dilution rate of 0.9 h1 and pH 4.3. Compared to the conventional acetone-butanol-ethanol fermentation, the new fermentation process greatly improved butanol yield, making butanol production from corn an attractive alternative to ethanol fermentation. 

For the ABE (acetone-butanol-ethanol) fermentation, PV-coupled MRs have been described using a... 

Cooksley, C.M., Zhang, Y, Wang, H., Redl, S. et al (2012) Targeted mutagenesis of the Clostridium acetobutylicum acetone-butanol-ethanol fermentation pathway. Metab. Eng., 14, 630-641. 

Liu, H. et al (2015) Integrated, systems metabolic picture of acetone-butanol-ethanol fermentation by Clostridium acetobutylicum. 

Vrana DL, Meagher MM, Hutkins RW, Duffield B. 1993. Pervaporation of model acetone-butanol-ethanol fermentation product solutions using polytetrafluoroethylene membranes. Sep. Sci. Technol. 28 2167-2178. 

The interest in w-butanol as a biofuel has increased in recent years owing to its superior fuel qualities compared to ethanol. These include a higher octane number, lower heat of vaporization, higher energy density (energy/volume), and lower vapor pressure. However, in the traditional ABE (acetone-butanol-ethanol) fermentation process, the concentration of n-butanol coming from the fermenter is lower than that achieved in ethanol fermentation. In addition, acetone and ethanol are also produced. Recent studies to improve yield and increase w-butanol concentration have explored fed-batch systems with stripping, adsorption, liquid-liquid extraction, distillation, and/or pervaporation to recover products. 

Cooksley CM, ZhangY, Wang H, Redl S, Winzer K, Minton NP.Targeted mutagenesis of the Clostridium acetohutylicum acetone-butanol-ethanol fermentation pathway. Metab Eng 2012 14 630-41. 

Li, J., Baral, N.R., and Jha, A.K. (2014) Acetone-butanol-ethanol fermentation of corn stover by Clostridium species present status and future perspectives. World J. Microbiol Biotechnol, 30, 1145-1157. 

Somrutai W, Takagi M, Yoshida T (1996) Acetone-butanol fermentation by Clostridium aurantibutyricum ATCC 17777 from a model medium for palm oil mill effluent. J Ferment Bioengin 81 543-547 Spivey MJ (1978) The acetone/butanol/ethanol fermentation. Proass Biochem... 

Butanol is naturally synthesised by Clostridia in a process called ABE (acetone-butanol-ethanol) fermentation. Butanol pathway, within ABE fermentation, consists of condensing two acetyl-CoA molecules (catalysed by a thiolase) and then reducing the product to butanol (requiring four reductases and one dehydratase). 

So far, the only known natural butanol produced are numerous clostridial species in a process called ABE (acetone-butanol-ethanol) fermentation. Butanol pathway in ABE fermentation consists of condensing two acetyl-CoA molecules (catalysed by a thiolase) and then reducing the product to butanol (requiring four reductases and one dehydratase). Except butanol, acetone and ethanol, Clostridia can also synthesise different chiral substances whose classical chemical synthesis would be challenging (Rogers et al. 1986), and they can degrade several toxic compounds (Francis et al. 1994 Spain 1995). 

Some of the Limitations Associated With Acetone-Butanol-Ethanol Fermentation... 

Engineered Acetone—Butanol-Ethanol Fermentation Pathway 443... 

FIGURE 23.4 Biochemical pathways of acetone-butanol-ethanol fermentation in Clostridium acetobutylicum. Reactions prevailing during the acidogenic phase of the fermentation are shown with dotted arrows, and reactions prevailing during the solventogenic phase are displayed by thick arrows (Kamm, 2015). 

Engineered Acetone-Butanol-Ethanol Fermentation Pathway... 

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