Butyric acid pathway

Clostridiwn butyricum Butyric acid 37°C, pH range between 5.0 and 7.0, medium 1053 Reinforced clostridial medium, anaerobic Butyric acid pathway... 

Propionic acid pathway C6H12O6 + 2H2 2CH3CH2C00H + 2H2O Butyric acid pathway... 

Butane-Naphtha Catalytic Liquid-Phase Oxidation. Direct Hquid-phase oxidation ofbutane and/or naphtha [8030-30-6] was once the most favored worldwide route to acetic acid because of the low cost of these hydrocarbons. Butane [106-97-8] in the presence of metallic ions, eg, cobalt, chromium, or manganese, undergoes simple air oxidation in acetic acid solvent (48). The peroxidic intermediates are decomposed by high temperature, by mechanical agitation, and by action of the metallic catalysts, to form acetic acid and a comparatively small suite of other compounds (49). Ethyl acetate and butanone are produced, and the process can be altered to provide larger quantities of these valuable materials. Ethanol is thought to be an important intermediate (50) acetone forms through a minor pathway from isobutane present in the hydrocarbon feed. Formic acid, propionic acid, and minor quantities of butyric acid are also formed. 

The reaction conditions, normally applied, are those described in chap. 2 for the radical pathway. These are a platinum anode, high current densities, no additives and a slightly acidic medium. However, the dimerizations shown in Table 2, No. 2, also gave in some cases good yields at a carbon anode in acetonitrile-water [52] or at a baked carbon anode in methanol [48]. With propionic and butyric acid an unusually high portion of alkene is formed at the cost of the dimer. 

Short chain fatty acids Sodium butyrate MCE310 Pathway analysis shows activity [36]... 

During cheese production lactose is converted to lactic acid by starter lactic acid bacteria (LAB). Any unfermented lactose is converted to d- and L-lactate by nonstarter lactic acid bacteria (NSLAB) and racemization, respectively. Lactate can be oxidized by LAB in cheese to acetate, ethanol, formic acid, and carbon dioxide at a rate dependent on oxygen availability (McSweeney, 2004). Other pathways include conversion to propionate, acetate, water, and carbon dioxide by Propionibacterium spp. carbon dioxide and water by Penicillium spp. yeasts and butyric acid and hydrogen by Clostridium spp. The rate of lactose metabolism influences proteolysis and flavor formation (Creamer et al., 1985 Fox et al., 1990). 

Figure 4.8 Hydrocarboxylation and carbonylation of propylene and n-propyl iodide. The outer cycle is the hydrocarboxylation pathway, while the inner cycle is the carbonylation pathway. The carbonylation pathway generates only n-butyric acid iodide. Note that 4.27 is identical with 4.5. A different designation is used to avoid cross-...

In some mammalian cells, enzymes comprising partial spans of biosynthetic pathways are inside and some outside the mitochondrial matrix space. Therefore, in the liver, six mitochondrial membrane transport proteins are required for urea synthesis, three for gluconeogenesis [7,8], and three others participate in ammonia-genesis [9] in the kidney. The synthesis of neurotransmitter substances such as acetylcholine, glutamate and y-amino butyric acid requires the participation of metabolite transporters in mitochondrial membranes of nervous tissue [9,10]. 

The initial step in the metabolism of short-chain fatty acids, w hether In cells of the gut lining or in the liver, is conversion to the coenzyine A derivative. For example, acetate is converted to acetyl coeuzyme A (acetyl CoA). The acetyl Co A formed in the cytoplasm can be used for the synthesis of fatly acids, w hereas that formed In the mitochondria can be used for immediate oxidation. Propioriyl CoA can be metabolized as shown in Figure8.7 in Chapter 8. Butyric acid can enter the mitochondria for conversion to butyryl CoA and oxidation in the pathway of fatty acid oxidation. 

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 ... 

In the oxidation of butyric acid by the /J-oxidation pathway, 1 mol each of FADH, and NADH and two mol of acetyl-CoA are produced. 

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