ISOLEUCINE- ▸ Nutritional supplement: Branched-chain amino-acid ingredient for dietary supplements and foods.
- ▸ Flavoring agent: Food flavoring ingredient.
- ▸ Research & culture media: Substrate for biochemical research.
- ▸ Cosmetic ingredient: Antistatic and skin-conditioning agent.
A grade-specific Safety Data Sheet (SDS) — with the complete hazard classification, handling precautions, and transport information — is supplied with every shipment and available on request. Confirm all safety and regulatory details against the SDS for your specific grade.
Request SDS →L-Isoleucine (CAS 73-32-5) is an essential branched-chain alpha-amino acid (C6H13NO2). It is used as a nutritional supplement and food flavoring ingredient, as a substrate in biochemical research and culture media, and as an antistatic and skin-conditioning ingredient in cosmetics.
Regulatory & registration requirements
- TSCA (US):
- REACH (EU):
- EC number: 200-798-2
Source: EPA TSCA Inventory (July 2025 release) · ECHA CHEM — retrieved 2026-07-12
Frequently Asked Questions
What is L-Isoleucine used for?
L-Isoleucine (CAS 73-32-5) is an essential branched-chain alpha-amino acid (C6H13NO2). It is used as an amino-acid ingredient in dietary supplements and foods, as a food flavoring ingredient, as a substrate in biochemical research and culture media, and as an antistatic/skin-conditioning ingredient in cosmetics.
Is L-Isoleucine a branched-chain amino acid (BCAA)?
Yes. L-isoleucine is one of the three branched-chain amino acids, alongside leucine and valine, which is why it is a standard input for BCAA blends and amino-acid formulations.
Is L-Isoleucine water soluble?
L-isoleucine is soluble in water, supporting its use in liquid supplement systems and in amino-acid culture media as a defined component.
What is the CAS number, formula, and HS code?
CAS 73-32-5, formula C6H13NO2, HS 2922.49 (amino-acids and their salts, other). Supplied to USP specification; lot-specific Certificate of Analysis and SDS are available on request.
What bulk packaging and order quantities are available?
It is distributed as a USP-grade ingredient in bulk packaging for manufacturing. Submit your target volume and USP/CoA documentation needs through a bulk RFQ for current pricing, pack sizes, and lead time.
What is the REACH and TSCA regulatory status of L-Isoleucine (Isoleucine)?
L-Isoleucine (Isoleucine) (CAS 73-32-5) is subject to U.S. TSCA Inventory requirements; supplying it into the EU requires valid REACH registration ((EC) No 1907/2006). RawSource cannot verify a third-party supplier's registrations — buyers should require documented TSCA and REACH compliance for their jurisdiction and volume (EC 200-798-2).