Taurine is also produced by the transsulfuration pathway, which converts homocysteine into cystathionine. Hypotaurine is enzymatically oxidized to yield taurine by hypotaurine dehydrogenase. Cysteine sulfinic acid, in turn, is decarboxylated by sulfinoalanine decarboxylase to form hypotaurine. In this pathway, cysteine is first oxidized to its sulfinic acid, catalyzed by the enzyme cysteine dioxygenase.
Mammalian taurine synthesis occurs in the pancreas via the cysteine sulfinic acid pathway.
Taurine is naturally derived from cysteine. In the laboratory, taurine can be produced by alkylation of ammonia with bromoethanesulfonate salts. Most of these enterprises employ the ethanolamine method to produce a total annual production of about 3,000 tonnes. As of 2010, China alone has more than 40 manufacturers of taurine. In 1993, about 5,000–6,000 tonnes of taurine were produced for commercial purposes: 50% for pet food and 50% in pharmaceutical applications. A direct approach involves the reaction of aziridine with sulfurous acid. Synthetic taurine is obtained by the ammonolysis of isethionic acid (2-hydroxyethanesulfonic acid), which in turn is obtained from the reaction of ethylene oxide with aqueous sodium bisulfite. The sulfonic acid has a low p K a ensuring that it is fully ionized to the sulfonate at the pHs found in the intestinal tract. Taurine exists as a zwitterion H 3N +CH 2CH 2SO − 3, as verified by X-ray crystallography. It is an unusual example of a naturally occurring sulfonic acid.Ĭhemical and biochemical features Taurine concentrations in land plants are very low or undetectable, but up to 1000 nmol/g wet weight have been found in algae. It is essential for cardiovascular function, and development and function of skeletal muscle, the retina, and the central nervous system. It has many biological roles, such as conjugation of bile acids, antioxidation, osmoregulation, membrane stabilization, and modulation of calcium signaling. It was discovered in human bile in 1846 by Edmund Ronalds. It is named after Latin taurus ( cognate to Ancient Greek ταῦρος, taûros) meaning bull or ox, as it was first isolated from ox bile in 1827 by German scientists Friedrich Tiedemann and Leopold Gmelin. It is a major constituent of bile and can be found in the large intestine, and accounts for up to 0.1% of total human body weight. The present study indicate that a high energy drink consumed 40 minutes before exercise can enhance exercise performance by increasing the total time to fatigue during incremental testing.Taurine ( / ˈ t ɔː r iː n/), or 2-aminoethanesulfonic acid, is a non-proteinogenic amino sulfonic acid that is widely-distributed in animal tissues. Significant difference between groups over time was observed in maximal heart rate, heart rate recovery and time to exhaustion (p < 0.05). Analysis of variance revealed no differences between supplement and placebo group in strength, CMJ, VJ and maximal oxygen uptake (VO2max) (p > 0.05). Before the second trial, they were randomly provided either a placebo (PLA maltodextrin) or the supplement (NP commercially marketed as Ultimate Nox PumpTM,). Subjects underwent two testing session separated by 7 days, consisted of handgrip strength test, countermovement (CMJ) and vertical jump (VJ) as well as incremental test to exhaustion on motorized treadmill. A randomized, double-blind, placebo-controlled research study design was conducted. ABSTRACT The effect of a pre-exercise energy sport drink on the exercise performance was examined in twenty recreationally active subjects.
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