Description
The most metabolically active branched-chain amino acid (BCAA) and the principal trigger for muscle protein synthesis through mTOR pathway activation. The supplement segment leader within the BCAA category since clinical research established its singular role in muscle protein synthesis signaling.
White crystalline powder. Slightly water-soluble.
We supply food-grade and pharmaceutical-grade L-Leucine from manufacturers in China holding ISO, Halal, Kosher and other certifications relevant to the product and production.
Common market grades include Standard Food Grade (FCC compliant), Pharmaceutical Grade meeting BP/USP/EP/JP specifications, Instant Leucine (modified for cold-water dispersion), and pre-blended BCAA Systems at the standard 2:1:1 ratio.
Bulk and reduced-MOQ shipments. Batch-level COA covering assay, specific rotation, related amino acids, heavy metals, and microbiology.
Introduction
L-Leucine is the largest branched-chain amino acid and the most metabolically active of the three BCAAs. The amino acid functions as the primary nutritional signal that triggers muscle protein synthesis through activation of the mTOR signaling pathway, an effect not produced by other amino acids.
Industrial production proceeds by submerged aerobic fermentation using engineered Corynebacterium glutamicum or Escherichia coli strains.
Recognized as a permitted food ingredient by the U.S. FDA, the European Food Safety Authority, and equivalent regulators worldwide. Listed in BP, USP, EP, and JP pharmacopoeias.
Clinical research over the 2010s established that leucine specifically (rather than total BCAAs or total protein) is the principal trigger for muscle protein synthesis after exercise or feeding. The threshold dose for maximal protein-synthesis response is approximately 2.5 to 3.0 grams of leucine, which has emerged as a key dosing target in modern protein-supplement formulation.
Strategic positioning has evolved from BCAA-blend supplements to standalone leucine and to high-leucine protein products (whey isolate, specifically). Sports nutrition remains the dominant application, with growing clinical-nutrition use in sarcopenia and elderly-nutrition contexts.
Where it is used
- Sports nutrition: the dominant single amino acid in modern muscle-protein-synthesis supplements
- BCAA supplement formulations at 2:1:1 ratio
- Pharmaceutical applications: parenteral nutrition formulas
- Clinical nutrition: sarcopenia-prevention and elderly-nutrition formulas
- Dietary supplements: muscle-mass and recovery-positioned products
- Infant formula fortification
- Pet food and aquaculture protein-balancing applications
- Animal feed: specialty applications including dairy and aquaculture
Technical data
| Item | Specification |
|---|---|
| Appearance | White crystalline powder |
| Assay (dry basis) | 98.5% to 101.0% |
| Specific rotation | +14.9° to +17.3° |
| Loss on drying | ≤ 0.3% |
| Residue on ignition | ≤ 0.1% |
| Heavy metals (as Pb) | ≤ 10 mg/kg |
| Chloride | ≤ 0.05% |
| Particle size | Per customer specification |
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