L-valine is an essential amino acid used in various industries, including the production of dietary supplements, pharmaceuticals, and nutritional products. The production of L-valine primarily involves chemical synthesis and fermentations. 

It is one of the three branched-chain amino acids (BCAAs), along with leucine and isoleucine, which are especially important for muscle repair and growth. Valine plays a crucial role in energy provision, stimulates muscle regeneration, and is involved in various metabolic processes.

When referring to "L-valine," the "L-" prefix specifies the molecule's orientation in three-dimensional space, indicating its chirality or "handedness." Amino acids can exist in two mirror-image forms, designated as L (Levo) and D (Dextro), which are like left and right hands. These forms are identical in their chemical formula but differ in their spatial arrangement, leading to different properties and activities in biological systems.

The L-form of amino acids, including L-valine, is the form that is biologically active in humans and is the form incorporated into proteins. This is because the enzymes that synthesize proteins in living organisms are specific for the L-form of amino acids. The D-forms of amino acids are not used in protein synthesis by most living organisms and can have different, sometimes harmful, effects on biological systems.

In summary, "valine" refers to the amino acid in general, without specifying its orientation, while "L-valine" specifically refers to the biologically active form of valine that is used in human metabolism and protein synthesis. 

 It's worth noting that D-forms of amino acids, including D-valine, exist and have different properties and less significance in human biology.

Industrial Production Process

• Raw Materials. The basic raw materials for the production of L-valine include carbon and nitrogen sources, such as sugars, ammonium, and nitrogen-containing compounds.
• Fermentation. The production of L-valine may involve bacterial fermentation, where microorganisms, often of the genus Corynebacterium, Escherichia coli, Corynebacterium glutamicum (1) are used to synthesize L-valine from suitable substrates.
• Extraction and Purification. After fermentation, L-valine can be extracted from the reaction mixture and subsequently purified to obtain a high-purity product.
• Crystallization. L-valine can be crystallized to obtain a purified solid form.
• Form and Color.

 L-Valine is commonly found as a white crystalline powder, soluble in water

What it is for and where

• Dietary Supplements and Sports Nutrition. L-Valine is one of the branched-chain amino acids (BCAAs) commonly used in dietary supplements and sports nutrition products to support muscle protein synthesis and repair after exercise
• Muscle Metabolism. Plays a crucial role in supporting muscle metabolism and providing energy during physical activity (2).
• Immune Function. It has been suggested that L-Valine may support immune function, though further research is needed to confirm these effects
• Liver Health. Some studies indicate that L-Valine may have beneficial effects on liver health, helping to prevent the accumulation of fat in the liver (3).
• Safety and Dosage. Generally considered safe when taken as part of a balanced diet or through supplements, but it's important not to exceed recommended doses to avoid potential side effects

Molecular Formula  C₅H₁₁NO₂

Molecular Weight  117.15 g/mol

CAS  72-18-4

UNII    HG18B9YRS7

EC Number   200-773-6

DTXSID40883233

References_____________________________________________________________________

(1) Wang X, Zhang H, Quinn PJ. Production of L-valine from metabolically engineered Corynebacterium glutamicum. Appl Microbiol Biotechnol. 2018 May;102(10):4319-4330. doi: 10.1007/s00253-018-8952-2. Epub 2018 Mar 29. PMID: 29594358.

Abstract. L-Valine is one of the three branched-chain amino acids (valine, leucine, and isoleucine) essential for animal health and important in metabolism; therefore, it is widely added in the products of food, medicine, and feed. L-Valine is predominantly produced through microbial fermentation, and the production efficiency largely depends on the quality of microorganisms. In recent years, continuing efforts have been made in revealing the mechanisms and regulation of L-valine biosynthesis in Corynebacterium glutamicum, the most utilitarian bacterium for amino acid production. Metabolic engineering based on the metabolic biosynthesis and regulation of L-valine provides an effective alternative to the traditional breeding for strain development. Industrially competitive L-valine-producing C. glutamicum strains have been constructed by genetically defined metabolic engineering. This article reviews the global metabolic and regulatory networks responsible for L-valine biosynthesis, the molecular mechanisms of regulation, and the strategies employed in C. glutamicum strain engineering.

(2) Gore DC, Wolfe RR. Metabolic response of muscle to alanine, glutamine, and valine supplementation during severe illness. JPEN J Parenter Enteral Nutr. 2003 Sep-Oct;27(5):307-14. doi: 10.1177/0148607103027005307.

Abstract. Background: Alanine and glutamine are released from muscle in response to critical illness. Subsequent depletion of glutamine from muscle is proposed as a principal factor in the limitation of muscle protein synthesis in severely ill patients. The objective of this study was to assess the peripheral metabolic response to enteral supplementation of alanine, glutamine, and valine in critically ill patients....Results: Compared with healthy volunteers, critically ill patients had significantly reduced concentrations of alanine and glutamine in arterial plasma (p < .05), which increased significantly with amino acid supplementation. Muscle glutamine concentrations were significantly less in the patients and were not significantly affected by supplementation. Alanine and glutamine transport into and out of muscle and the rates of alanine and glutamine incorporation into and production from muscle were not affected by supplementation. Phenylalanine kinetics, as a marker of muscle protein metabolism, were not significantly altered by alanine, glutamine, and valine intake. Conclusions: These results demonstrate that alanine, glutamine, and valine administration fails to significantly affect muscle glutamine availability or muscle protein metabolism. These findings suggest that accelerated muscle catabolism in critically ill patients is not in response to any deficiency in alanine or glutamine availability.

(3) Nakanishi C, Doi H, Katsura K, Satomi S. Treatment with L-valine ameliorates liver fibrosis and restores thrombopoiesis in rats exposed to carbon tetrachloride. Tohoku J Exp Med. 2010 Jun;221(2):151-9. doi: 10.1620/tjem.221.151. 

Abstract. It has been reported that treatment with branched chain amino acids (BCAAs) increases the survival rates in cirrhotic patients. In this study, we investigated the effect of L-valine, one of BCAAs, on liver fibrosis in rat. To induce liver fibrosis, male Wistar rats were injected carbon tetrachloride (CCl(4)) intraperitoneally (2.0 mL/kg) twice a week for 12 weeks. The rats (seven to fifteen rats for each group) were then administered 1.688 g/kg/day of L-valine intravenously for 7 days or 10% amino acid preparation that provided the same amount of nitrogen. Seven days after the last administration, blood platelet counts and bone marrow megakaryocyte counts were significantly higher in the valine group than in the control group (131.2 +/- 38.3 vs. 106.3 +/- 14.5 x 10(4)/microL, p = 0.04; 18.0 +/- 2.1 vs. 13.5 +/- 2.2 per field, p < 0.01, respectively). Importantly, the mRNA level of thrombopoietin, a key regulator of thrombopoiesis, was significantly higher in the liver of the valine group than the control group. Furthermore, hepatic fibrosis was significantly reduced in the valine group, and the mRNA levels of factors associated with liver fibrosis such as procollagen alpha1(III), transforming growth factor-beta1 and connective tissue growth factor were significantly lower in the liver of the valine group 10 days after the last administration. These results indicate that L-valine treatment ameliorates liver fibrosis and restores thrombopoiesis in rats exposed to CCl(4). Therefore, L-valine supplementation may be helpful for patients with liver cirrhosis.