Butyric acid fermentation

The third mode of energy conversion, fermentation, was discovered by Pasteur. After examining alcoholic fermentation by yeast, he studied several bacterial fermentations, including butyric acid fermentation and its... 

Reductive fermentations can be classified into the following types (1) butyric acid fermentation, (2) butanol-acetone fermentation, (3) butanol-isopropyl alcohol fermentation, (4) butylene glycol-ethanol fermentation, and (5) acetone-ethanol fermentation. 

We acknowledge Ying Zhu for helping to provide the information about butyric acid fermentation. This research was supported in part by a grant from the Department of Energy (DE-FG02-00ER86106). 

Pyruvate is the initial key intermediate in butyric acid fermentations and is formed via the Embden-Meyerhoff pathway. Pyruvate is cleaved to form CO2, H2, and acetyl-Coenzyme A (acetyl-CoA), which dimerizes to form acet-oacetyl-CoA ... 

Use To form esters, varnish components, soaps, metal soaps (resin soaps from abietates), additive in lactic and butyric acid fermentations. 

The pathway for the butyric acid fermentation in the Clostridia (and in fact all of the anaerobic bacteria that produce butyric acid) is illustrated in Fig. 3.2. 

Jiang, L., Wang, J., liang, S., Wang, X., Cen, P., Xu, Z., 2009a. Butyric acid fermentation in a fibrous bed bioreactor with immobUized Clostridium tyrobutyricum from cane molasses. Bioresource Technology 100 (13), 3403-3409. 

Baroi, G., Baumann, I., Westermann, R, Gavala, H., 2015. Butyric acid fermentation from pretreated and hydrolysed wheat straw by an adapted Clostridium tyrobutyricum strain. Microbial biotechnology 8 (5), 874—882. 

Zhu, Y, Liu, X., Yang, S.T., 2005. Construction and characterization of pta gene-deleted mutant of Clostridium tyrobu-tyricum for enhanced butyric acid fermentation. Biotechnology and Bioengineering 90 (2), 154 166. 

The fermoutatiou processes, wldcli in this case are Icnown to take place, are the alcoholic fermentation, tlie acetic acid fermentation, and the butyric acid fermentation. With yeast glycerine ferments at 20 to 30", with the formation of propionic acid with the... 

Fiber components are the principal energy source for colonic bacteria with a further contribution from digestive tract mucosal polysaccharides. Rate of fermentation varies with the chemical nature of the fiber components. Short-chain fatty acids generated by bacterial action are partiaUy absorbed through the colon waU and provide a supplementary energy source to the host. Therefore, dietary fiber is partiaUy caloric. The short-chain fatty acids also promote reabsorption of sodium and water from the colon and stimulate colonic blood flow and pancreatic secretions. Butyrate has added health benefits. Butyric acid is the preferred energy source for the colonocytes and has been shown to promote normal colonic epitheUal ceU differentiation. Butyric acid may inhibit colonic polyps and tumors. The relationships of intestinal microflora to health and disease have been reviewed (10). 

Buttersaure, /. butyric acid, -ather, tn. ethyl butyrate pi. butyric esters, -ganing, /, butyric fermentation. pilz, tn. butyric acid bacteria. 

Gknings-alkohol, m. ethyl alcohol, -amylal-kohol, m. amyl alcohol of fermentation (a mixture of 2- and 3- methylbutanol). -but-tersaure,/. (ordinary) butyric acid, -chemie, /. fermentation chemistry, zymurgy. 

Hydroxy-n-butyric acid 3 Carbapenem Antibacterial Hydroxylation Candida rugosa Single-stage fermentation [4]... 

Microorganisms have also been developed to produce alternative products, such as lactic acid [65], propane-1,3-diol [67], 3-hydroxypropionic acid [68], butane-2,3-diol [69] and numerous other intermediates. For instance, bacteria such as the Clostridium acetobutylicum ferment free sugars to C4 oxygenates such as butyric acid or butanol. They form the C4 oxygenates by Aldol condensation of the acetaldehyde intermediates. The Weizmann process exploits this property to ferment starch feedstock anaerobically at 37 °C to produce a mixture of w-butanol, acetone and ethanol in a volume ratio of 70 25 5 [3],... 

Schuster et al. reported work on monitoring a complex ace-tone-butanol-ethanol (ABE) fermentation system.22 They looked at the qualitative nature of the biomass as well as the solvents present in the liquid phase. A hierarchical cluster analysis was performed on samples from various times of the fermentation. The clusters were then classified using classical markers and analyses. The resultant table, combining qualitative interpretation and quantitative results, shows an interesting mosaic of the system over time. Total solvents, optical density, and butyric acid are given as numeric values in either absorbance units of g/1. 

These short-chain fatty acids are acetic, butyric, lactic and propionic acids, also known as volatile fatty acids, VFA. They are produced from fermentation of carbohydrate by microorganisms in the colon and oxidised by colonocytes or hepatocytes (see above and Chapter 4). Butyric acid is activated to produce butyryl-CoA, which is then degraded to acetyl-CoA by P-oxidation acetic acid is converted to acetyl-CoA for complete oxidation. Propionic acid is activated to form propionyl-CoA, which is then converted to succinate (Chapter 8). The fate of the latter is either oxidation or, conversion to glucose, via glu-coneogenesis in the liver. 

Later it was observed that butyric acid is a naturally occurring dietary HD AC inhibitor. It is formed upon dietary fiber fermentation within our digestive system. Although butyrate does not normally reach high enough levels for cancer treatment, it has been proposed that daily consumption over an individual s lifetime may provide chemoprevenfive effects. ... 

Bat-pollinated flowers have musky odors, resembling that of bats or fermentation. These flowers contain butyric acid, which smells to hiunans... 

More than seventy years ago the impressive discovery was made that bioreduction of mannitol, glycerol and starch yields butanol. Fermentations in which butyric acid, butanol and acetone are formed from carbohydrates by different bacilli (butyl bacteria) belong in this group. The term butyl bacteria as a generic name for microbes producing the genetically related substances of the four-carbon series was proposed in 1921" and has been applied since then. The approximate course of these reactions is shown by the following formulations which, however, do not explain the mechanism ... 

Important results have recently been obtained by Simon. Among other things he ascertained that glycerol yields butyric acid. The formation of four-carbon compounds from six-carbon substrates is independent of the grouping (aldehyde, hydroxyl, carboxyl, phosphory-lated hydroxyl) at the first carbon atom of the molecule. L-Rhamnose and D-arabitol are fermented, but not n-arabinose and D-sorbitol. In contrast to the studies of Underkofler and Hunter, " L-sorbose has been found fermentable. Results obtained with fresh and acetone-dried Cl. hutylicum are identical in principle. 

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