Oxidase lactic acid

Schmid et al. used the same principle to develop sensors to be incorporated into FI systems for the determination of ascorbic acid in fruit juices [38] and that of lactic acid in dairy products [39]. The membrane used in both applications consisted of decacyclene dissolved in silicone rubber that was treated similarly as the membrane in glucose sensors (Fig. 3.4.B). The oxygen optrode was coated with a sheet of carbon black as optical insulation in order to protect it from ambient light or intrinsic sample fluorescence. Ascorbic acid oxidase or lactic acid oxidase was immobilized by adsorbing it onto carbon black and cross-linking it with glutaraldehyde. The FI system automatically buffered and diluted the food samples, thereby protecting the biosensor from a low pH and interferents. 

On the other hand, the racemase material was unable to promote the oxidation of D-lactate by the L-lactic acid oxidases of pig heart or tobacco leaves. 

Lactic acid Immobilized lactate oxidase, luminol-H202 CL 5 mg/L 104... 

Cyanide ion exerts an inhibitory action on certain metabolic enzyme systems, most notably cytochrome oxidase, the enzyme involved in the ultimate transfer of electrons to molecular oxygen. Because cytochrome oxidase is present in practically all cells that function under aerobic conditions, and because the cyanide ion diffuses easily to all parts of the body, cyanide quickly halts practically all cellular respiration. The venous blood of a patient dying of cyanide is bright red and resembles arterial blood because the tissues have not been able to utilize the oxygen brought to them. Cyanide intoxication produces lactic acidosis, the result of an increased rate of glycolysis and production of lactic acid. ... 

Immobilized oxidase systems with oxygen electrode (lactic acid, alcohol) Toyo Jozo Co. Ltd., Japan... 

R. Garjonyte, Y. Yigzaw, R. Meskys, A. Malinauskas and L. Gorton, Prussian-blue and lactate oxidase-based amperometric biosensor for lactic acid, Sens. Actuators B, 79 (2001) 33-38. 

The production of substances that preserve the food from contamination or from oxidation is another important field of membrane bioreactor. For example, the production of high amounts of propionic acid, commonly used as antifungal substance, was carried out by a continuous stirred-tank reactor associated with ultrafiltration cell recycle and a nanofiltration membrane [51] or the production of gluconic acid by the use of glucose oxidase in a bioreactor using P E S membranes [52]. Lactic acid is widely used as an acidulant, flavor additive, and preservative in the food, pharmaceutical, leather, and textile industries. As an intermediate product in mammalian metabolism, L( +) lactic acid is more important in the food industry than the D(—) isomer. The performance of an improved fermentation system, that is, a membrane cell-recycle bioreactors MCRB was studied [53, 54], the maximum productivity of 31.5 g/Lh was recorded, 10 times greater than the counterpart of the batch-fed fermentation [54]. 

NS), respectively, cytochrome oxidase decreased 9%(NS). Treatment-related effects in wmn muscle citrate synthetase decreased 19% (NS), cytochrome oxidase increased 23% (NS), muscle lactate and lactic acid dehydrogenase affected. Subjects reported no adverse health effects after exposure. 

An interesting application for the oxidation of organic compounds is of electrochemical nature. Octacyano complexes have been used to monitor redox enzymes such as lactate oxidase (from Pediococcus sp.) and sarcosine oxidase (from Arthrobactersp.) in a suitable electrochemical system (114). Two equivalents of [M(CN)g] can, for example, be oxidized at the electrode surface to [M(CN)g], which in turn can oxidize the flavoproteien to its oxidized form. This in turn reacts with, for example, L-lactic acid to produce pyruvic acid. 

The Vitros analyzer (Ortho-Cfinical Diagnostics, Raritan, N.J.) uses an assay in which lactic acid is oxidized to pyruvate by lactate oxidase. The H2O2 generated oxidizes a chromogen system, and the absorbance of the resulting dye complex, measured by a spectrophotometer at 540nm, is directly proportional to the lactate concentration in the specimen. Each mole oflactate oxidized produces O.Smol of dye complex. 

The inhibition of cytochrome c oxidase, and resultant disturbance of electron transport, results in decreased mitochondrial O2 utilization and decreased ATP (Olsen and Klein, 1947). Anaerobic metabolism leads to an accumulation of lactic acid and lactate acidosis, and the combination of lactate acidosis and cytotoxic hypoxia causes severe metabolic disturbances, particularly in the central nervous system (CNS), resulting in disturbances of perception and consciousness. 

K. Hajisadeh, et. al., Immobihzation of lactate oxidase in a poly(vinyl alcohol) matrix on platinized graphite electrodes by chemical cross-linking with isocyanate, Talanta, 38 (1), 37-47 (1991). (lactic acid in dairy products). 

Production of citric acid, enzymes (such as amylases, invertase, proteases, glucose oxidase, and pectinase), fumaric acid, gluconic acid, and lactic acid... 

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