Kojic acid was first discovered in Japan in 1907. Kojic acid is a chelation agent produced by several species of fungi, especially Aspergillus oryzae, which has the Japanese common name koji. Kojic acid is a by-product in the fermentation process of malting rice, for use in the manufacturing of sake, the Japanese rice wine. 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. It forms a bright red complex with ferric ions. Kojic acid may be used on cut fruits to prevent oxidative browning, in seafood to preserve pink and red colors, and in cosmetics. In skin care products, kojic acid functions primarily as a skin-lightening agent. It is a potent tyrosinase inhibitor. It penetrates the upper skin layers and inhibits the production of epidermal melanin. As an example of the latter, it is used to treat skin diseases like melasma. Kojic acid also has antibacterial and antifungal properties. The cocrystals of kojic acid with quercetin were found to have two times better cytotoxic activity to human cervical cancer cells (HeLa) and human colon cancer cells (Caco-2) in comparison with quercetin itself.