Kojic acid is a pyranone that is 4H-pyran substituted by a hydroxy group at position 5, a hydroxymethyl group at position 2 and an oxo group at position 4. It has been isolated from the fungus Aspergillus oryzae. It has a role as a NF-kappaB inhibitor, an Aspergillus metabolite, a skin lightening agent, an EC 1.10.