L-lysine is an L-alpha-amino acid; the L-isomer of lysine.
How much products actually contain
8 products state the amountmedian 0.000042%
- under 0.01% 8
- 0.01–0.1% 0
- 0.1–1% 0
- 1% or more 0
Amounts are mostly stated by products named after the ingredient, so they may lean towards token amounts.
Of the products containing it, 105 list it before the 1% line and 419 after it (usually 1% or less).
Products using this ingredient
12 of 522 confirmed · likeliest to carry enough first · See all 522
ElastineAmino Peptide Weak Acid Protein High Nutrition Shampoo Pear & Freesia Scent0.0001% stated
Living ProofLiving Proof Perfect hair Day™ Style Refresh Mist
BENTONBenton Honest Eyelash Serum
ElastinePerfume Conditioner Pure Breeze
ENOUGHRich Gold Intensive Pro Nourishing Ampoule
HAIRPLUSProtein Bond Water Essence 200ml 2-Pack
MuradMurad Targeted Pore Corrector
ElastineMarine Collagen Volume Treatment
HAIRPLUSProtein Bond Ampoule Essence 150ml Wiggle Wiggle Limited Edition
Summer FridaysSummer Fridays Deluxe Cloud Dew (10ml)
Summer FridaysSummer Fridays Mini Cloud Dew Gel Cream
HAIRPLUSProtein Bond Ampoule Modern Peach 70ml 2-Pack
Definition
L-lysine is an L-alpha-amino acid; the L-isomer of lysine. It has a role as a micronutrient, an anticonvulsant, a nutraceutical, a mouse metabolite, a Saccharomyces cerevisiae metabolite, a plant metabolite, an Escherichia coli metabolite, a human metabolite and an algal metabolite. It is a L-alpha-amino acid, an aspartate family amino acid, a lysine and a proteinogenic amino acid. It is a conjugate base of a L-lysinium(1+). It is a conjugate acid of a L-lysinate. It is an enantiomer of a D-lysine. It is a tautomer of a L-lysine zwitterion and a L-Lysine zwitterion.
Source: PubChem
US FDA substance register · UNII K3Z4F929H6 · registered name Lysine · single chemical substance
Cosmetic roles
Safety & regulatory references
Not classified under Korea’s toxic-substance GHS list · existing chemical substance
Reviewed by CIR: Safety Assessment of alpha-Amino Acids as Used in Cosmetics
More data — names, identifiers, properties, test records, literature
Official labels & definitions
JCIA labelling name リシン: 本品は、次の化学式で表されるアミノ酸である。
Source: JCIA labelling names (Japan)
Names & identifiers
- CAS No.chemical registry number
- 56-87-1
- EC No.EU chemical inventory number
- 200-294-2
- DTXSIDUS EPA chemical ID
- DTXSID6023232
- DTXCIDUS EPA compound ID
- DTXCID403232
- IUPAC
- L-Lysine
- Molecular formula
- C6H14N2O2
- Molecular weight
- 146.19 g/mol
Measured properties
- Appearance
- Solid, [Merck Index] · Solid
- Melting point
- 224.5 dec °C · 224 °C, decomposes
- Solubility
- 1000000 mg/L (at 20 °C) · Insoluble in ethanol, ethyl ether, acetone, benzene
- Dissociation constant
- 3.12 (at 0 °C) · pK1 = 2.18, pK2 = 8.95, pK3 = 10.53 at 38 °C
- Colour
- colourless
- Melting/freezing point
- 224~225 ℃
- Initial boiling point and range
- 290 ℃
- Flash point
- 211 ℃
- Upper/lower flammability or explosive limits
- 10.1 / 1.2 %
- n-Octanol/water partition coefficient (Kow)
- -3.05
- Decomposition temperature
- 212-225 ℃
- Molecular weight
- 146.19
Values measured on the substance itself. The KOSHA data are a reference for writing and reviewing safety data sheets, not a specification for a commercial raw material.
Source: PubChem · KOSHA safety data sheets (Korea)
What products actually use it for
What the 13 products reported to the US EPA with this ingredient use it for. Products outside cosmetics are included, so the top few rows are its main uses.
- Flavouring and nutrient5
- Pharmaceutical (EPA)3
- Solvent2
- Softener and conditioner2
- Anti-static agent1
Source: US EPA CompTox dashboard
Related literature
- Enhancing ε-Poly-L-lysine Production in Streptomyces albulus through L-lysine Importer Engineering. · 2025
- Safety and efficacy of a feed additive consisting of concentrated liquid l‐lysine, l‐lysine monohydrochloride and concentrated liquid l‐lysine monohydrochloride produced by Escherichia coli NITE BP‐02917 for all animal species (Metex NoovistaGo) · 2022
- Safety of concentrated l‐lysine (base), l‐lysine monohydrochloride and l‐lysine sulfate produced using different strains of Corynebacterium glutamicum for all animal species based on a dossier submitted by FEFANA asbl · 2019
- Mechanism of Lysine on the Formation of Glycyrrhetic Acid Elastic Vesicles · 2011
- A molecular tweezer for lysine and arginine. · 2005
Linked databases 20
- Australian Industrial Chemicals Inventory (AICIS)
- ChEBI
- ChEMBL
- China inventory of existing ingredients (IECIC)
- EU CosIng ingredient list 2
- JCIA labelling names (Japan)
- Korea Cosmetic Association ingredient dictionary
- Korea toxic substances GHS register (NIER)
- KOSHA safety data sheets (Korea)
- MFDS (Korea) cosmetic ingredient register 2
- NIST Chemistry WebBook
- PubChem 2
- Tlooto literature search 2 3 4 5
- UniChem cross-reference IDs
- US Cosmetic Ingredient Review (CIR) 2
- US EPA CompTox dashboard 2
- US EPA DSSTox chemical database
- US FDA substance registration (GSRS)
- US FDA Unique Ingredient Identifier (UNII)
- Wikidata