Lactate from Glucose

The assay described is that of Pilone and Kunkee (1972) and Edwards et al. (1991). The form of lactic acid (d or l) can be quantified by using any commercial assay kits including those available from Boehringer Mannheim GMBH. 

5 g liver extract with 50mL distilled water for at least 30 min. Filter the suspension through Whatman no. 1 filter paper. 

To one portion (250mL) of the autoclaved medium, add ImL of a filter-sterilized (0.45 pm membrane) 5% w/v glucose solution. 

Distribute the media into sterile 18 x 150mm tubes at lOmL per tube. 

Prepare a heavy inoculum of lactic acid bacteria as follows. 

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When animal tissues cannot be supplied with sufficient oxygen to support aerobic oxidation of the pyruvate and NADH produced in glycolysis, NAD+ is regenerated from NADH by the reduction of pyruvate to lactate. As mentioned earlier, some tissues and cell types (such as erythrocytes, which have no mitochondria and thus cannot oxidize pyruvate to C02) produce lactate from glucose even under aerobic conditions. The reduction of pyruvate is catalyzed by lactate dehydrogenase, which forms the l isomer of lactate at pH 7 ... 

The apparent yield of lactate from glucose, provides an estimate of the... 

Fig. 1.8 Asaccharolytic fermentation produces ammonia and short-chain fatty acids. This group of fermentations by oral bacteria utilizes proteins, which are converted to peptides and amino acids. The free amino acids are then deaminated to ammonia in a reaction that converts nicotinamide adenine dinucleotide (NAD) to NADH. For example, alanine is converted to pyruvate and ammonia. The pyruvate is reduced to lactate, and ammonium lactate is excreted into the environment. Unlike lactate from glucose, ammonium lactate is a neutral salt. The common end products in from plaque are ammonium acetate, ammonium propionate, and ammonium butyrate, ammonium salts of short chain fatty acids. For example, glycine is reduced to acetate and ammonia. Cysteine is reduced to propionate, hydrogen sulfide, and ammonia alanine to propionate, water, and ammonia and aspartate to propionate, carbon dioxide, and ammonia. Threonine is reduced to butyrate, water, and ammonia and glutamate is reduced to butyrate, carbon dioxide, and ammonia. Other amino acids are involved in more complicated metabolic reactions that give rise to these short-chain amino acids, sometimes with succinate, another common end product in plaque.

The astrocytes are found in the CNS and are star-shaped cells that provide physical and nutritional support for neurons. During development of the CNS, the astrocytes guide neuronal migration to their final adult position and form a matrix that keeps neurons in place. These cells serve several functions, including the ability to phago-cytose debris left behind by cells, to provide lactate (from glucose metabolism) as... 

The sprint is essentially anaerobic and produces lactate from glucose by glycolysis. Lactate is then recycled to glucose by gluconeogenesis. 

Aside from the superior catalysts mentioned above, Osmundsen et al. have reported the use of hydrothermally synthesized Sn-SBA-15, Sn-MCM-41, and Sn-MFl for sucrose to methyl lactate in methanol, but their yields ranged between 20% and 30% [122]. A similar 18% yield was reported for the parent material of the Sn-CSM catalysts. This mesoporous stannosilicate was made via Sn grafting procedure [66], Murillo et al. reported a yield of 43% of methyl lactate from glucose, with a different hydrothermal Sn-MCM-41 [140]. Apart from tin-catalysts, Liu et al. reported on the use of basic MgO in MeOH, but only 30% of methyl lactate was formed for glucose and other hexoses at a high 200°C [141],... 

Any excess lactate is taken up by the liver, converted into pyruvate and then into glucose. This, along with the production of lactate from glucose in muscle cells, constitutes the Cori cycle. 

Xiaodong W, Xuan G, Rakshit SK (1997) Direct fermentative production of lactic acid on cassava and other starch substrates. Biotechnol Lett 19 841-843. doi 10.1023/A 1018321200591 Yadav AK, Chaudhari AB, Kothari RM (2011) Bioconversion of renewable resources into LA an industrial view. Grit Rev Biotechnol 1 1-19. doi 10.3109/07388550903420970 Yamane T, Tanaka R (2013) Highly acciunulative production of L (-H)-lactate from glucose by crystallization fermentation with immobilized Rhizopus oryzae. J Biosci Bioeng 115(1) 90-95.doi 10.1016/j.jbiosc.2012.08.005... 

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