Kojic acid

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Kojic acid
KojicAcid.svg
Identifiers
CAS number 501-30-4 YesY
PubChem 3840
ChemSpider 3708 YesY
UNII 6K23F1TT52 YesY
EC number 207-922-4
DrugBank DB01759
KEGG C14516 YesY
ChEBI CHEBI:43572 N
ChEMBL CHEMBL287556 YesY
RTECS number UQ0875000
Jmol-3D images Image 1
Properties
Molecular formula C6H6O4
Molar mass 142.11 g/mol
Appearance white
Melting point 152 - 155 °C
Solubility in water Slight
Acidity (pKa) 9.40[1]
Hazards
R-phrases R36/37/38
S-phrases S22, S24/25
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
 N (verify) (what is: YesY/N?)
Infobox references

Kojic acid is a chelation agent produced by several species of fungi, especially Aspergillus oryzae, which has the Japanese common name koji.[2][3] Kojic acid is a by-product in the fermentation process of malting rice, for use in the manufacturing of sake, the Japanese rice wine.[2] It 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.[4] It forms a bright red complex with ferric ions.

Biosynthesis[edit]

13C-Labeling studies have revealed at least two pathways to kojic acid. In the usual route, dehydratase enzymes convert glucose to kojic acid. Also reduces the signs of redness. Pentoses are also viable precursors in which case dihydroxyacetone is invoked as an intermediate.[2]

Applications[edit]

Kojic acid may be used on cut fruits to prevent oxidative browning, in seafood to preserve pink and red colors, and in cosmetics to lighten skin. As an example of the latter, it is used to treat skin diseases like melasma.[5] Kojic acid also has antibacterial and antifungal properties.[citation needed]

References[edit]

  1. ^ Bjerrum, J., et al. Stability Constants, Chemical Society, London, 1958.
  2. ^ a b c R. Bentley, "From miso, sake and shoyu to cosmetics: a century of science for kojic acid", Nat. Prod. Rep. 2006, 23, 1046-1062.
  3. ^ Yabuta T (1924). "The constitution of kojic acid, a gamma-pyrone derivative formed by Aspergillus oryzae from carbohydrates". Journal of the Chemical Society 125: 575–587. doi:10.1039/ct9242500575. 
  4. ^ Kojic acid and enzymatic browning
  5. ^ Melasma, American Academy of Dermatology

External links[edit]