PROLINE
2-Pyrrolidinecarboxylic acid, (S)-
PROLINE is listed in the EU CosIng inventory, but no direct annex records are linked on this page yet.
Regulatory evidence by market
No rule for this ingredient has been imported for any of the 13 markets tracked here.
That describes this inventory, not the law. No imported rule is not evidence that an ingredient is permitted: a rule may exist under another name or identifier, or in a dataset not yet imported here.
Chemical identity and properties
L-Proline
L-proline is pyrrolidine in which the pro-S hydrogen at position 2 is substituted by a carboxylic acid group. L-Proline is the only one of the twenty DNA-encoded amino acids which has a secondary amino group alpha to the carboxyl group. It is an essential component of collagen and is important for proper functioning of joints and tendons. It also helps maintain and strengthen heart muscles. It has a role as a member of compatible osmolytes, a micronutrient, a nutraceutical, a mouse metabolite, a Saccharomyces cerevisiae metabolite, an Escherichia coli metabolite and an algal metabolite. It is a L-alpha-amino acid, a glutamine family amino acid, a proline and a proteinogenic amino acid. It is a conjugate base of a L-prolinium. It is a conjugate acid of a L-prolinate. It is an enantiomer of a D-proline. It is a tautomer of a L-proline zwitterion. — ChEBI
- IUPAC name
- (2S)-pyrrolidine-2-carboxylic acid
- Molecular formula
- C5H9NO2
- Molecular weight
- 115.13 g/mol
- Exact mass
- 115.063328530 Da
- XLogP3
- -2.5
- Topological polar surface area
- 49.3 Ų
- Hydrogen-bond donors
- 2
- Hydrogen-bond acceptors
- 3
- Covalent units
- 1
- Defined stereocentres
- 1
Also known as
16 more reported names
External database identifiers
- ChEBI:CHEBI:17203
- ChEMBL:CHEMBL54922
- EPA DTXSID:DTXSID5044021
- PubMed:29968805
- PubMed:23062336
- PubMed:22989233
- PubMed:22988852
- PubMed:22986818
- PubMed:22946499
- PubMed:22924394
- PubMed:22915995
- PubMed:22878559
- PubMed:22833679
- PubMed:22829593
- PubMed:22740038
Retrieved from NIH PubChem on 2026-08-31 by checksum-valid CAS matching. Chemical properties do not replace the regulatory decision on this page.
proline dl-form
Proline is an alpha-amino acid that is pyrrolidine bearing a carboxy substituent at position 2. It has a role as a human metabolite and a Daphnia magna metabolite. It is an alpha-amino acid and a member of pyrrolidines. It is a conjugate base of a prolinium. It is a conjugate acid of a prolinate. — ChEBI
- IUPAC name
- pyrrolidine-2-carboxylic acid
- Molecular formula
- C5H9NO2
- Molecular weight
- 115.13 g/mol
- Exact mass
- 115.063328530 Da
- XLogP3
- -2.5
- Topological polar surface area
- 49.3 Ų
- Hydrogen-bond donors
- 2
- Hydrogen-bond acceptors
- 3
- Covalent units
- 1
- Defined stereocentres
- 0
Also known as
16 more reported names
External database identifiers
Retrieved from NIH PubChem on 2026-08-31 by checksum-valid CAS matching. Chemical properties do not replace the regulatory decision on this page.
Inventory details for PROLINE
INCI name
PROLINE
INN name
proline
Description
2-Pyrrolidinecarboxylic acid, (S)-
Record provenance
- Inventory reference
- 78685
- Imported identity
- PROLINE
- Source update
- 15/10/2010
Annex records for PROLINE
Key data
- HAIR CONDITIONING
- Enhancing the appearance and feel of hair. Leaving the hair easy to comb, supple, soft and shiny and/or imparting volume, lightness, gloss, texture, etc.
- SKIN CONDITIONING
- Maintaining the skin in good condition.
Official EU ingredient-name evidence
The ingredient name exactly matches the official 2025 EU glossary of common ingredient names.
Related inventory evidence
Ingredients with overlapping formulation functions
Additional official and scientific sources
11 external databases to check this identity in
Each link searches that source for this identity. What each source is, and its legal weight
How PROLINE appears in the CosIng inventory
The CosIng inventory lists PROLINE as a cosmetic ingredient and this page links it to 0 annex records. The inventory entry captures names and identifiers, while the annex records show where the substance is prohibited, restricted or positively listed in EU cosmetics law.
PROLINE is also tagged with 2 cosmetic functions in the official data. Function labels describe intended use, but they do not replace regulatory review of linked annex records before formulation or labelling work.
Frequently asked questions
Source note for PROLINE
This page reproduces the CosIng inventory entry for PROLINE from public European Commission cosmetic ingredient materials and shows linked identifiers even when no direct annex match is currently attached.
Use this inventory page to research PROLINE and compare linked records, but verify restrictions and legal status against the current official source text and law before making regulatory decisions.
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