L-Leucine
L-Leucine bulk ingredient for B2B formulation sourcing. Request a specification sheet, batch COA, and documentation from GEM.
| 规格名称 | 规格值 |
|---|---|
| Assay | 98.5–101.5% HPLC |
| Standard | USP33 |
| CAS No. | 61-90-5 |
| Appearance | White crystals or crystalline powder |
| Shelf Life | 24 months |
| Packing | 25 kg/drum |
L-Leucine
L-Leucine (CAS 61-90-5) is an essential branched-chain amino acid (BCAA) supplied by GEM at 98.5–101.5% HPLC (USP33) purity for sports nutrition, EAA blends, and pharmaceutical formulations. GEM provides bulk L-Leucine powder to global B2B customers, including supplement brands, contract manufacturers, and food-fortification companies that require a reliable, document-backed raw material.
L-Leucine Powder Quick View
Specification: 98% HPLC, USP33
Certificate: ISO22000; ISO9001; ISO14001; FSSC22000; Kosher; Halal
Features: Essential branched-chain amino acid (BCAA); Pharma-grade white crystalline powder; Supports muscle protein synthesis; Suitable for sports nutrition and dietary supplement formulations
Application: Sports nutrition; BCAA & EAA powder blends; Dietary supplements; Pharmaceutical raw materials; Nutritional fortification; Food additives; Amino acid IV preparations
Main function: Muscle protein synthesis signaling; Post-workout recovery support; Essential amino acid fortification; Metabolic regulation
Packing: 25kg/drum
Shelf Life: 24 months
Storage: Stored in closed containers in a cool, dry, well-ventilated area. Last updated: June 21, 2026
CAS No.: 61-90-5
Molecular formula: C6H13NO2
What Is L-Leucine?
L-Leucine (CAS 61-90-5) is an essential amino acid with the molecular formula C6H13NO2. It is classified as one of the three branched-chain amino acids (BCAAs), together with L-isoleucine and L-valine. Because the human body cannot synthesize L-Leucine, it must be obtained through diet or supplementation.
At room temperature, L-Leucine appears as white crystals or crystalline powder with a slightly bitter taste. It has a melting point of 293–295°C, is slightly soluble in ethanol, and is insoluble in ether. Among the BCAAs, L-Leucine is widely recognized as the primary amino acid driving muscle protein synthesis (MPS) through activation of the mTOR signaling pathway — making it a cornerstone ingredient in sports nutrition, pre-workout, post-workout, and recovery formulations.
As a bulk raw material, pharmaceutical-grade L-Leucine powder is procured by supplement brands, contract manufacturers, and food fortification companies for BCAA blends, essential amino acid (EAA) premixes, protein powders, capsules, tablets, and functional beverages. GEM supplies L-Leucine meeting USP33 chromatographic purity requirements, with full certification support for global B2B markets. For brands sourcing a reliable leucine manufacturer, consistent assay and documentation are decisive factors in formulation planning.
Within the human body, L-Leucine is one of nine essential amino acids that must be obtained from external sources. Of the 20 standard amino acids used to build proteins, the three BCAAs occupy a special metabolic niche. For product developers, this means an L-Leucine supplement or BCAA powder must be sourced from a supplier that can support both purity and batch-to-batch consistency. That is exactly the gap GEM's specification-controlled bulk supply is built to close.
L-Leucine at a Glance
- Chemical identity: L-Leucine, also known as 2-amino-4-methylpentanoic acid
- Category: Essential amino acid; branched-chain amino acid (BCAA)
- Purity grade: USP33, 98.5%–101.5% assay by HPLC
- Physical form: White crystalline powder
- Supply format: Bulk 25kg/drum for B2B manufacturing
L-Leucine Source & Chemistry
L-Leucine belongs to the group of branched-chain amino acids, a term that describes the distinctive branched aliphatic side chain attached to the amino acid backbone. This structural feature distinguishes the three BCAAs — L-Leucine, L-isoleucine, and L-valine — from the other proteinogenic amino acids. The hydrophobic side chain of L-Leucine contributes to its physical behavior, including limited solubility in water and organic solvents such as ether.
Why BCAAs Are Different
Unlike most amino acids, which are metabolized primarily in the liver, branched-chain amino acids are notably metabolized in skeletal muscle. This peripheral metabolism is one reason BCAAs — and L-Leucine in particular — are so frequently featured in sports nutrition and recovery products. The branched aliphatic side chain of L-Leucine is handled in the body through transamination to α-ketoisocaproate, an intermediate in the metabolism of branched-chain amino acids. This muscle-centered handling, rather than first-pass clearance in the liver, is a key reason BCAAs are studied separately from other amino acids in exercise and recovery nutrition.
Because the body cannot synthesize L-Leucine endogenously, it is classified as an essential amino acid and must be supplied through dietary protein or supplementation. Dietary L-Leucine is found in protein-rich foods such as meat, poultry, fish, eggs, and dairy. Plant-based sources include soy, legumes, and pulses, which is why formulators often combine L-Leucine with pea protein powder or brown rice protein to build complete, plant-forward amino acid profiles.
Chemical and Physical Properties
| Property | Description |
|---|---|
| Molecular formula | C6H13NO2 |
| CAS number | 61-90-5 |
| Appearance | White crystals or crystalline powder |
| Taste | Slightly bitter |
| Melting point | 293–295°C |
| Solubility | Slightly soluble in ethanol; insoluble in ether |
These properties inform how L-Leucine powder is handled, blended, and incorporated into finished formulations. The stable crystalline form supports accurate dosing in dry blends, capsules, and tablets produced by contract manufacturers.
L-Leucine Specification
GEM supplies L-Leucine tested against USP33 chromatographic purity standards. The full specification below represents the quality parameters verified for each batch.
| Testing Item | Specification |
|---|---|
| Appearance | White crystals or crystalline powder |
| Assay | 98.5%～101.5% |
| Specific rotation | +14.9°~+17.3° |
| PH | 5.5-7.0 |
| Loss on drying(%) | ≤ 0.2% |
| Residue on ignition(%) | ≤ 0.4% |
| Chloride(%) | ≤ 0.05% |
| Sulfate(%) | ≤ 0.03% |
| Heavy Metals | ≤ 15ppm |
| Iron(Fe) | ≤ 0.003% |
| Chromatographic purity | As per USP33 |
Every batch is released against this specification with a corresponding Certificate of Analysis (COA). B2B buyers can request specification sheets, COA documents, and certification files to support regulatory review and inbound quality control. The tight assay window of 98.5%–101.5% by HPLC gives formulators confidence that label claims will hold across production runs.
L-Leucine Application Fields
L-Leucine powder is a versatile raw material used across sports nutrition, dietary supplements, pharmaceuticals, and food fortification. The table below summarizes the principal application fields and typical formulations.
| Application Field | Typical Use & Formulations |
|---|---|
| Sports Nutrition & BCAA Formulations | Pre-workout, intra-workout, and post-workout powders; blended with L-isoleucine and L-valine (commonly 2:1:1) for muscle recovery and endurance support |
| Dietary Supplements | Standalone amino acid raw material or EAA complexes, protein powders, capsules, and tablets for athletes, fitness enthusiasts, and active-aging consumers |
| Pharmaceutical & Medical Preparations | Amino acid intravenous infusions, comprehensive amino acid preparations, and parenteral nutrition where USP-grade purity is required |
| Food & Nutritional Fortification | Dietary enhancer in bread, flour-based products, meal replacements, and functional foods needing essential amino acid supplementation |
| Flavor Enhancement & Food Additives | Spice or flavoring agent to improve the sensory profile of food products |
1. Sports Nutrition & BCAA Formulations: L-Leucine is the most sought-after BCAA for pre-workout, intra-workout, and post-workout powders. It is commonly blended with L-isoleucine and L-valine in 2:1:1 or custom ratios for muscle recovery and endurance support. Formulators often pair L-Leucine with L-Citrulline-DL-Malate for nitric oxide support or L-arginine for complementary amino acid profiles.
2. Dietary Supplements: Used as a standalone amino acid raw material or combined in EAA (essential amino acid) complexes, protein powders, capsules, and tablets targeting athletes, fitness enthusiasts, and active-aging consumers. L-Theanine is a common co-ingredient in recovery and focus blends alongside BCAA formulations.
3. Pharmaceutical & Medical Preparations: Applied in amino acid intravenous infusions, comprehensive amino acid preparations, and parenteral nutrition formulations where USP-grade purity is required.
4. Food & Nutritional Fortification: Functions as a dietary enhancer in bread, flour-based products, meal replacements, and functional foods requiring essential amino acid supplementation.
5. Flavor Enhancement & Food Additives: Acts as a spice or flavoring agent to improve the overall sensory profile of food products.
Formulation & Blending Considerations
When building a BCAA powder, formulators commonly start from the classic 2:1:1 ratio of L-Leucine, L-isoleucine, and L-valine, though custom ratios are widely used depending on the product positioning. Because L-Leucine delivers the primary anabolic signal, many modern L-Leucine supplement formulas increase the leucine proportion or supply it as a standalone ingredient. The white crystalline powder blends cleanly with other amino acids, plant proteins, and functional additives, and its chemical stability supports a long shelf life in finished goods. GEM's consistent 98.5%–101.5% HPLC assay helps manufacturers keep label claims accurate across production runs and simplify documentation for new product registrations.
Production & Quality Assurance
GEM's L-Leucine is manufactured under ISO22000, ISO9001, FSSC22000, ISO14001 food safety and quality management systems, with Kosher and Halal certification available for global distribution.
Each batch is tested to USP33 chromatographic purity standards. Standard packaging is 25kg/drum with a shelf life of 24 months when stored in closed containers in a cool, dry, well-ventilated area. Certificate of Analysis (COA), specification sheets, and certification documents are provided to support B2B procurement and regulatory compliance.
Certifications & Compliance
| Certificate | Scope |
|---|---|
| ISO22000 | Food safety management |
| ISO9001 | Quality management system |
| ISO14001 | Environmental management |
| FSSC22000 | Food safety system certification |
| Kosher | Kosher certification |
| Halal | Halal certification |
Packaging, Storage & Logistics
- Packing: 25kg/drum
- Shelf life: 24 months
- Storage: Stored in closed containers in a cool, dry, well-ventilated area, away from direct sunlight and moisture
- Documentation: COA, specification sheet, and certification files supplied with each order
For bulk L-Leucine powder inquiries — including sample requests, custom documentation, and export logistics — contact GEM's sales team. Choosing a dependable leucine manufacturer with verified certifications simplifies market entry and speeds up product registration for international buyers.
Frequently Asked Questions
1. What is the difference between L-Leucine and BCAA?
L-Leucine is a single essential amino acid and one of the three branched-chain amino acids (BCAAs). A BCAA product typically combines L-Leucine, L-isoleucine, and L-valine — often in a 2:1:1 ratio. L-Leucine is considered the most important BCAA for muscle protein synthesis and is frequently used as a standalone raw material or as the dominant component in BCAA blends.
2. What quality standard does GEM's L-Leucine meet?
Our L-Leucine meets USP33 chromatographic purity requirements with an assay of 98.5%–101.5% by HPLC. Appearance is white crystals or crystalline powder. Full specification and batch COA are available upon request.
3. What certifications are available for bulk L-Leucine?
GEM's L-Leucine is produced under ISO22000, ISO9001, FSSC22000, and ISO14001 management systems. Kosher and Halal certifications are available to support supplement, food, and pharmaceutical markets globally.
4. What is the standard packaging and shelf life?
Standard packaging is 25kg/drum. Shelf life is 24 months when stored in closed containers in a cool, dry, well-ventilated area away from direct sunlight and moisture.
5. What are the main B2B applications for L-Leucine powder bulk supply?
Primary applications include sports nutrition (BCAA/EAA powders, pre-workout, post-workout), dietary supplement manufacturing (capsules, tablets, protein blends), pharmaceutical amino acid preparations, and food/nutritional fortification. L-Leucine powder is the preferred procurement format for contract manufacturers and supplement brands requiring precise dosing.
7. Is L-Leucine suitable for plant-based or vegan formulations?
Yes. L-Leucine supplied by GEM is a fermentation- or synthesis-derived amino acid raw material rather than an animal extract, and it is available with Kosher and Halal certification. It pairs well with plant proteins such as pea protein powder and brown rice protein to complete amino acid profiles in vegan products.
8. Can L-Leucine be blended with other amino acids?
Absolutely. L-Leucine is regularly combined with L-isoleucine and L-valine in BCAA blends, with other EAAs in complete amino acid premixes, and with complementary ingredients such as L-ornithine L-aspartate or L-phenylalanine depending on the target formulation.
9. What documentation is provided with each batch?
Each order ships with a Certificate of Analysis (COA), a specification sheet, and the relevant certification files (ISO, Kosher, Halal as applicable). Custom documentation for import clearance and regulatory submission can be arranged on request.
10. How should L-Leucine powder be stored?
Store L-Leucine in closed containers in a cool, dry, well-ventilated area, protected from direct sunlight and moisture. Under these conditions the shelf life is 24 months from the date of manufacture.
Further Reading
Explore related amino acids, plant proteins, and company updates from GEM:
- L-Arginine — complementary amino acid for sports and wellness blends
- L-Arginine Hydrochloride — alternative salt form for formulation flexibility
- L-Citrulline-DL-Malate — common BCAA stack partner for nitric oxide support
- L-Ornithine L-Aspartate — amino acid raw material for parenteral nutrition
- Pea Protein Powder — plant protein for complete amino acid profiles
- Major Pea Protein Factory Update — GEM production and capacity news