Chemical Properties
A white, odorless powder having a sweet taste
Chemical Properties
White crystalline powder
Physical properties
pI 6.01, dissociation constants: pK1 2.34, pK2 9.69.
Occurrence
Natural constituent of protein in plants and animals; found in apple, beef, carob, pea, soybean, wine and
zucchini
Definition
ChEBI: The L-enantiomer of alanine.
Preparation
Anthrobacter oxydans HAP-1 hyper produces DL-alanine in a nongrowth-associated manner.
Production Methods
L -Alanine is industrially produced from L -aspartic acid by means of immobilized Pseudomonas dacunhae cells in a pressurized bioreactor. An alanine racemase-deficient mutant of Arthro-bacter oxydans was reported, that produces75 g/L L -alanine from glucose with a yield of 52% and 95% e.e. A small amount of L -alanine is still isolated from protein hydrolysates.
General Description
L-Alanine, a non-essential amino acid,?is produced enzymatically from?L-aspartate using aspartate β-decarboxylase.?It is the smallest among all the amino acids.
Pharmaceutical secondary standards for application in quality control, provide pharma laboratories and manufacturers with a convenient and cost-effective alternative to the preparation of in-house working standards.
Biochem/physiol Actions
L-Alanine is a nonessential amino acid, which is highly concentrated in muscle. It is a key player in the Glucose-Alanine cycle, which enables the removal of pyruvate and glutamate from muscle to the liver. Once in the liver, glucose is regenerated from pyruvate and returned to the muscle while glutamate ultimately participates in the urea cycle to form urea. The Glucose-Alanine cycle aides to conserve ATP in muscle for muscle contraction, while the energy burden of gluconeogenesis is imposed upon the liver. Alanine inhibits pyruvate kinase to regulate gluconeogenesis and glycolysis in order to maintain glucose homeostasis during starvation. Alanine prevents hepatic autophagy. Alanine formation is a result of transamination of glutamate and pyruvate.
Purification Methods
Crystallise alanine from H2O or aqueous EtOH, i.e. crystallise it from 25% EtOH in water, or recrystallise it from 62.5% EtOH, wash it with EtOH and dry it to constant weight in vacuo over P2O5. [Gutter & Kegeles J Am Chem Soc 75 3893 1953, Walsh J Biol Chem 264 2394 1989.] 2,2'-Iminodipropionic acid is a likely impurity. [Beilstein 4 IV 2480. 2481.]
