ContaminantDB: Kojic acid

Identification Taxonomy Biological Properties Physical Properties Toxicity Profile Spectra Concentrations Links References Targets (4)XML

Record Information

Version

1.0

Creation Date

2010-05-21 16:18:59 UTC

Update Date

2026-04-02 22:50:28 UTC

Accession Number

CHEM002736

Identification

Common Name

Kojic acid

Class

Small Molecule

Description

Kojic acid is a synthetic intermediate for production of food additives. Kojic acid has been shown to exhibit anti-neoplastic function (4).

Contaminant Sources

Cosmetic Chemicals
FooDB Chemicals
IARC Carcinogens Group 3
T3DB toxins
ToxCast & Tox21 Chemicals

Contaminant Type

Ester
Food Toxin
Fungal Toxin
Industrial/Workplace Toxin
Metabolite
Mycotoxin
Natural Compound
Organic Compound

Chemical Structure

MOL SDF PDB SMILES InChI

Synonyms

Value	Source
5-Hydroxy-2-(hydroxymethyl)-4-pyrone	ChEBI
5-Hydroxy-2-hydroxymethyl-4-pyrone	ChEBI
Acido kojico	ChEBI
Kojisaeure	ChEBI
Kojate	Generator
2-(Hydroxymethyl)-5-hydroxy-4H-pyran-4-one	HMDB
2-Hydroxymethyl-5-hydroxy-gamma-pyrone	HMDB
5-Hydroxy-2-(hydroxymethyl)-4H-pyran-4-one	HMDB
5-Hydroxy-2-(hydroxymethyl)pyran-4-one	HMDB
5-Hydroxy-2-hydroxymethyl-4H-4-pyranone	HMDB
KOJ	HMDB
Pyran-4-one, 5-hydroxy-2-(hydroxymethyl)	HMDB
Kojyl-appa	MeSH, HMDB
5-((3-Aminopropyl)phosphinooxy)-2-(hydroxymethyl)-4H-pyran-4-one	MeSH, HMDB

Chemical Formula

C₆H₆O₄

Average Molecular Mass

142.109 g/mol

Monoisotopic Mass

142.027 g/mol

CAS Registry Number

501-30-4

IUPAC Name

5-hydroxy-2-(hydroxymethyl)-4H-pyran-4-one

Traditional Name

kojic acid

SMILES

OCC1=CC(=O)C(O)=CO1

InChI Identifier

InChI=1S/C6H6O4/c7-2-4-1-5(8)6(9)3-10-4/h1,3,7,9H,2H2

InChI Key

BEJNERDRQOWKJM-UHFFFAOYSA-N

Chemical Taxonomy

Description

belongs to the class of organic compounds known as pyranones and derivatives. Pyranones and derivatives are compounds containing a pyran ring which bears a ketone.

Kingdom

Organic compounds

Super Class

Organoheterocyclic compounds

Class

Pyrans

Sub Class

Pyranones and derivatives

Direct Parent

Pyranones and derivatives

Alternative Parents

Substituents

Pyranone
Heteroaromatic compound
Cyclic ketone
Oxacycle
Organic oxygen compound
Organic oxide
Hydrocarbon derivative
Aromatic alcohol
Primary alcohol
Organooxygen compound
Alcohol
Aromatic heteromonocyclic compound

Molecular Framework

Aromatic heteromonocyclic compounds

External Descriptors

primary alcohol (CHEBI:43572 )
pyranone (CHEBI:43572 )
enol (CHEBI:43572 )

Biological Properties

Status

Detected and Not Quantified

Origin

Exogenous

Cellular Locations

Cytoplasm
Extracellular

Biofluid Locations

Not Available

Tissue Locations

Not Available

Pathways

Not Available

Applications

Not Available

Biological Roles

Aspergillus metabolite

Chemical Roles

NF-kappaB inhibitor

Physical Properties

State

Solid

Appearance

Tan powder.

Experimental Properties

Property	Value
Melting Point	161°C
Boiling Point	Not Available
Solubility	Not Available

Predicted Properties

Property	Value	Source
Water Solubility	92.3 g/L	ALOGPS
logP	-1	ALOGPS
logP	-0.5	ChemAxon
logS	-0.19	ALOGPS
pKa (Strongest Acidic)	9.3	ChemAxon
pKa (Strongest Basic)	-3.1	ChemAxon
Physiological Charge	0	ChemAxon
Hydrogen Acceptor Count	4	ChemAxon
Hydrogen Donor Count	2	ChemAxon
Polar Surface Area	66.76 Å²	ChemAxon
Rotatable Bond Count	1	ChemAxon
Refractivity	35.27 m³·mol⁻¹	ChemAxon
Polarizability	12.63 Å³	ChemAxon
Number of Rings	1	ChemAxon
Bioavailability	1	ChemAxon
Rule of Five	Yes	ChemAxon
Ghose Filter	No	ChemAxon
Veber's Rule	No	ChemAxon
MDDR-like Rule	No	ChemAxon

Spectra

Spectrum Type	Description	Splash Key	View
GC-MS	GC-MS Spectrum - GC-MS (2 TMS)	splash10-00di-3950000000-d1e6f5b2e47ac5626c5f	Spectrum
GC-MS	GC-MS Spectrum - EI-B (Non-derivatized)	splash10-05p6-9300000000-704def65872ec878b268	Spectrum
GC-MS	GC-MS Spectrum - EI-B (Non-derivatized)	splash10-00ko-9500000000-8c8ed21581e5ce62d657	Spectrum
GC-MS	GC-MS Spectrum - EI-B (Non-derivatized)	splash10-00dj-0972200000-d2e1134bffb7759fab36	Spectrum
GC-MS	GC-MS Spectrum - GC-EI-TOF (Non-derivatized)	splash10-00dj-1940000000-7a8f18adc19d5275d098	Spectrum
GC-MS	GC-MS Spectrum - GC-MS (Non-derivatized)	splash10-00di-3950000000-d1e6f5b2e47ac5626c5f	Spectrum
Predicted GC-MS	Predicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positive	splash10-03kc-6900000000-d96f98a42148a6e47233	Spectrum
Predicted GC-MS	Predicted GC-MS Spectrum - GC-MS (2 TMS) - 70eV, Positive	splash10-00di-9650000000-945de47e75f8ec9b9eaf	Spectrum
Predicted GC-MS	Predicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positive	Not Available	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - LC-ESI-QTOF , negative	splash10-0006-0900000000-7497f496112e599fe169	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - Linear Ion Trap , negative	splash10-001i-9200000000-79391fb0052779fa15a9	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - 10V, Negative	splash10-0006-0900000000-7497f496112e599fe169	Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum - 10V, Positive	splash10-0006-0900000000-b4f5c76df606bee2639b	Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum - 20V, Positive	splash10-0006-1900000000-8c591424fe1f23b4f463	Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum - 40V, Positive	splash10-0a6r-9300000000-2f1a2b3413e8f032697f	Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum - 10V, Negative	splash10-0006-0900000000-a3e3f8a5e8ce22a6cba3	Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum - 20V, Negative	splash10-01ox-2900000000-4f881cf1625489e94838	Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum - 40V, Negative	splash10-052f-9000000000-82a828b03c7d45e6515f	Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum - 10V, Positive	splash10-004l-1900000000-9f54abebd3fd9066985d	Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum - 20V, Positive	splash10-00ov-9600000000-4e5e43090310b4854d93	Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum - 40V, Positive	splash10-0006-9100000000-20c19898fd61a4ca36ac	Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum - 10V, Negative	splash10-0006-0900000000-781e0069db86c3955b89	Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum - 20V, Negative	splash10-0006-9400000000-c6bf0fd6d0995684723a	Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum - 40V, Negative	splash10-0006-9000000000-63243637491eb161d9df	Spectrum
MS	Mass Spectrum (Electron Ionization)	splash10-00kf-9400000000-15508d600420b309e528	Spectrum
1D NMR	1H NMR Spectrum	Not Available	Spectrum
1D NMR	13C NMR Spectrum	Not Available	Spectrum
1D NMR	1H NMR Spectrum	Not Available	Spectrum
1D NMR	13C NMR Spectrum	Not Available	Spectrum
1D NMR	1H NMR Spectrum	Not Available	Spectrum
1D NMR	13C NMR Spectrum	Not Available	Spectrum
1D NMR	1H NMR Spectrum	Not Available	Spectrum
1D NMR	13C NMR Spectrum	Not Available	Spectrum
1D NMR	1H NMR Spectrum	Not Available	Spectrum
1D NMR	13C NMR Spectrum	Not Available	Spectrum
1D NMR	1H NMR Spectrum	Not Available	Spectrum
1D NMR	13C NMR Spectrum	Not Available	Spectrum
1D NMR	1H NMR Spectrum	Not Available	Spectrum
1D NMR	13C NMR Spectrum	Not Available	Spectrum
1D NMR	1H NMR Spectrum	Not Available	Spectrum
1D NMR	13C NMR Spectrum	Not Available	Spectrum
1D NMR	1H NMR Spectrum	Not Available	Spectrum
1D NMR	13C NMR Spectrum	Not Available	Spectrum
1D NMR	1H NMR Spectrum	Not Available	Spectrum
1D NMR	13C NMR Spectrum	Not Available	Spectrum

Toxicity Profile

Route of Exposure

Oral, dermal, inhalation, and parenteral (contaminated drugs). (3)

Mechanism of Toxicity

Kojic acid acts as a competitive and reversible inhibitor of animal and plant polyphenol oxidases (tyrosinases), xanthine oxidase, and D- and some L-amino acid oxidases. Inhibition of tyrosinases prevents melanosis, while inhibition of the oxidases prevents metabolism of certain amino acids. Kojic acid also reversibly affects thyroid function by inhibiting iodine uptake, leading to decreases in thyroid hormones T3 and T4 and increases in thyroid-stimulating hormone (TSH). Increased TSH from pituitary gland in turn stimulates thyroid hyperplasia. (1, 2)

Metabolism

Kojic acid is absorbed by the gastrointestinal tract, enters the circulation, and is probably metabolized similar to hexoses. (1)

Toxicity Values

Not Available

Lethal Dose

Not Available

Carcinogenicity (IARC Classification)

3, not classifiable as to its carcinogenicity to humans. (5)

Uses/Sources

Kojic acid is a chelation agent and mycotoxin produced by several species of Aspergillus, Acetobacter, and Penicillium fungi, especially Aspergillus oryzae, which has the Japanese common name koji. Kojic acid is a by-product in the fermentation process of malting rice, and is used in the manufacturing of numerous foods, including miso, soy sauce, and sake. Kojic acid is a mild inhibitor of the formation of pigment in plant and animal tissues, and is used in food and cosmetics to preserve or change colors of substances, such as in skin-lightening or bleaching formulas. It is also used as a food additive for preventing enzymatic browning and in seafood to preserve pink and red colors. Kojic acid also has antibacterial and antifungal properties and is used in skin diseases like melasma. (6, 1)

Minimum Risk Level

Not Available

Health Effects

Animals studies have shown that kojic acid increases the occurrence of thyroid cancer and thyroid adenomas, though it is not known whether this is also true in humans. (1)

Symptoms

Sensitive individuals may develop contact dermatitis. (1)

Treatment

Not Available

Concentrations

Not Available

External Links

DrugBank ID

DB01759

HMDB ID

HMDB0032923

FooDB ID