Kojic acid: history, properties, biosynthesis, and applications

The name kojic acid was acquired from "Koji," a fungus or starter inoculum consumed in Japanese oriental food. Kojic acid is produced by several species of Aspergillus as a secondary metabolite. Commercially, kojic acid (5-hydroxy-2-hydroxymethyl-δ-pyrone) is produced by Aspergillus species in aerobic fermentation. Kojic acid has various applications in many industries including cosmetics, medicine, food, agriculture, and chemicals. It is used as an antimicrobial anticancer, tyrosinase inhibitor, insecticide, and pesticide. In the last few years, production and demand for kojic acid have increased due to its huge commercial value in various industries. This chapter shed light on the history, properties, and biosynthetic pathway for the production of kojic acid by fungi. Also, advances in the kojic acid fermentation process have been discussed. Some derivatives of kojic acid and its applications in industries are also described.