murphyLeucine
AKA: L-leucine, 61-90-5, (S)-Leucine, (S)-2-Amino-4-methylpentanoic acid, (2S)-2-amino-4-methylpentanoic acid, (S)-2-Amino-4-methylvaleric acid, (S)-(+)-Leucine, L-alpha-Aminoisocaproic acid
Synthetic
Skin Conditioner
Hair Care
Clean
OriginLeucine is a branched-chain amino acid synthesized from petroleum-derived starting materials or fermentation feedstocks. It is produced through microbial fermentation or chemical synthesis via transamination and purification processes.
Leucine (abbreviated as Leu or L)[2] is a branched-chain л±-amino acid with the chemical formulaHO2CCH(NH2)CH2CH(CH3)2. Leucine is classified as a hydrophobic amino acid due to its aliphatic isobutyl side chain. It is encoded by six codons (UUA, UUG, CUU, CUC, CUA, and CUG) and is a major component of the subunits in ferritin, astacin, and other 'buffer' proteins. Leucine is an essential amino acid, meaning that the human body cannot synthesize it, and it therefore must be ingested. It is important for hemoglobin formation.
Solubility 21500
Formula
C6H13NO2
Mol. Weight
131.17
CAS #
61-90-5
Form
Powder
State
White solid; [Merck Index] White powder; [Sigma-Aldrich MSDS]
Skin Types
●all-skin-types
Best For
Dryness
Pregnancy & Breastfeeding Safe
Yes
Functions
Antistatic
Hair Conditioning
A catch-all term for ingredients that improve how skin looks and feels — softer, smoother, more supple. The workhorse behind most moisturizers.
Skin Conditioning
A catch-all term for ingredients that improve how skin looks and feels — softer, smoother, more supple. The workhorse behind most moisturizers.
Locks in moisture
The paper trail
🔬Peer-reviewed1 paper →
⚖️Regulatory1 listing →
🛡️Safety-assessed2 reviews →
Counts, not a verdict. A listing isn't a study. The trail, you decide.
Verified Jun 2026
Data: PubChem · CosIng · EWG · CIR