5-oxo-L-proline is an optically active form of 5-oxoproline having L-configuration.
How much products actually contain
No product states its amount yet.
Of the products containing it, 62 list it before the 1% line and 127 after it (usually 1% or less).
Products using this ingredient
12 of 184 confirmed · likeliest to carry enough first · See all 184
DALEAFChlorella Anti-Hair Loss Hair Tonic
NaturopathicaNaturopathica Gotu Kola + Fruit Exosome Rejuvenating Essence
Herbivore BotanicalsHerbivore Botanicals GREEN MAGIC Centella + Ceramides Soothing Face Serum
Act+AcreAct+Acre Daily Hydro™ Scalp Serum
R+CoR+Co CENTERPIECE 10-IN-1 Conditioning Spray
R+CoR+Co CENTERPIECE 10-IN-1 Conditioning Spray - Mini
PATTERN BeautyPATTERN Beauty Blow Out Primer
OLAPLEXOLAPLEX No.7 Shine Serum Oil Mist
Anastasia Beverly HillsAnastasia Beverly Hills Clear Brow Gel
Anastasia Beverly HillsAnastasia Beverly Hills Mini Clear Brow Gel
OUAIOUAI Leave In Conditioner Melrose Place
OUAIOUAI Leave In Conditioner Melrose Place - Travel
Definition
5-oxo-L-proline is an optically active form of 5-oxoproline having L-configuration. It has a role as an algal metabolite. It is a 5-oxoproline, a non-proteinogenic L-alpha-amino acid and a L-proline derivative. It is a conjugate acid of a 5-oxo-L-prolinate. It is an enantiomer of a 5-oxo-D-proline.
Source: PubChem
US FDA substance register · UNII SZB83O1W42 · registered name Pidolic Acid · single chemical substance
Cosmetic roles
Safety & regulatory references
Not classified under Korea’s toxic-substance GHS list · existing chemical substance
Other restriction: ban substances that deplete the ozone layer
Source: EU CosIng ingredient list
Reviewed by CIR: Safety Assessment of PCA (2-pyrrolidone-5-carboxylic acid) and its Salts as Used in Cosmetics
Reviewed by CIR: Final Safety Assessment for PCA and Sodium PCA
More data — names, identifiers, properties, test records, literature
Official labels & definitions
JCIA labelling name ＰＣＡ: 本品は、次の化学式で表される複素環式化合物である。
Source: JCIA labelling names (Japan)
Names & identifiers
- CAS No.chemical registry number
- 98-79-3
- EC No.EU chemical inventory number
- 202-700-3
- EC No.EU chemical inventory number
- 205-748-3
- DTXSIDUS EPA chemical ID
- DTXSID6046260
- DTXCIDUS EPA compound ID
- DTXCID4026260
- IUPAC
- 5-Oxo-L-proline
- Molecular formula
- C5H7NO3
- Molecular weight
- 129.115 g/mol
Measured properties
- Appearance
- Solid, [Merck Index] White crystalline powder, [Alfa Aesar MSDS] · Solid
- Melting point
- 184.7 °C
- Solubility
- 476000 mg/L (at 13 °C) · 476.0 mg/mL at 13 °C
- Colour
- white
- Melting/freezing point
- 220 ℃
- Relative density
- 2.54
- Molecular weight
- 129.13
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 5 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.
- Humectant4
- Flavouring and nutrient1
Source: US EPA CompTox dashboard
Related literature
- Temporal and qualitative analysis of injured decomposed skin tissues using ATR-FTIR combined with chemometrics. · 2026 · Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy
- Label-free imaging and machine learning reveal cyclin-dependent kinase 6 (CDK6)-regulated metabolic phenotypes and beige potential in single preadipocytes. · 2026 · Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy
- Evaluation of porcine ear skin as a model for human skin: influence on the diffusion of different photosensitizers. · 2026 · Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy
- Metabolomic Mapping of Greek Olive Leaves by Untargeted NMR-Based Profiling and LC-HRMS Dereplication. · 2026 · Analytical science advances
- Non-invasive time inference of repetitive contusion injuries using hyperspectral imaging and machine learning. · 2026 · Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy
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
- PubMed 2 3 4 5
- UniChem cross-reference IDs
- US Cosmetic Ingredient Review (CIR) 2 3
- US EPA CompTox dashboard 2
- US EPA DSSTox chemical database
- US FDA substance registration (GSRS)
- US FDA Unique Ingredient Identifier (UNII)
- Wikidata