Бета-аланин

Описание

β-Alanine (or beta-alanine) is a naturally occurring beta amino acid, which is an amino acid in which the amino group is at the β- position from the carboxylate group (i.e., two atoms away. The IUPAC name for β-alanine is 3-amino propanoic acid. Unlike its counterpart α-alanine, β-alanine has no stereocenter.
β-Alanine is not used in the biosynthesis of any major proteins or enzymes. It is formed in vivo by the degradation of dihydrouracil and carnosine. It is a component of the naturally occurring peptides carnosine and anserine and also of pantothenic acid (vitamin B5), which itself is a component of coenzyme A. Under normal conditions, β-alanine is metabolized into acetic acid.
β-Alanine is the rate-limiting precursor of carnosine, which is to say carnosine levels are limited by the amount of available β-alanine. Supplementation with β-alanine has been shown to increase the concentration of carnosine in muscles, decrease fatigue in athletes and increase total muscular work done.
Typically, studies have used supplementing strategies of multiple doses of 400 mg or 800 mg, administered at regular intervals for up to eight hours, over periods ranging from 4 to 10 weeks . After a 10 - week supplementing strategy, the reported increase in intramuscular carnosine content was an average of 80.1% (range 18 to 205%).

Химические свойства

This is a secondary amino acid, which is formed in vivo by the degradation of dihydrouracil and carnosine. Because neuronal uptake and neuronal receptor sensitivity to β-alanine have been demonstrated, the compound may be a false transmitter replacing GABA. A rare genetic disorder, hyper-β-alaninemia, has been reported. It is used as a flavor enhancer, flavoring agent, nutrient supplement or adjuvant. β-Alanine has a slightly sweet taste.

Вхождение

Reported to occur as a component in amino acids; carnosine, anserine, pantothenic acid

Использование

β-Alanine is a naturally occurring beta amino acid. β-Alanine is formed in vivo by the degradation of dihydrouracil (D449990) and carnosine. β-Alanine is also the rate-limiting precursor of carnosine, as a result supplementation with β-alanine increases the concentration of carnosine in muscles.

Определение

ChEBI: A naturally-occurring beta-amino acid comprising propionic acid with the amino group in the 3-position.

Подготовка

By heating acrylic acid with concentrated aqueous ammonia under pressure, by addition of acrylonitrile to phthalimide or to ammonia; from β-aminopropionitrile, from succinimide by the Hofmann degradation.

Общее описание

An N-blocked form of alanine.

Методы очистки

Crystallise β-alanine by dissolving it in a hot saturated aqueous solution, filtering, adding four volumes of absolute EtOH and cooling in an ice-bath. Recrystallise it in the same way and then finally, crystallise it from a warm saturated solution in 50% EtOH and adding four volumes of absolute EtOH with cooling in an ice-bath. The crystals are dried in a vacuum desiccator over P2O5. [Donovan & Kegeles J Am Chem Soc 83 255 1961, Beilstein 4 IV 2526.]