Kojic acid is a kind of specialized inhibitor for melanin. It can prevent the tyrosinase activity through synthesizing with copper ion in the cells after it enters skin cells. Kojic acid and its derivative has better inhibitory effect on tyrosinase than any other skin whitening agents. At present it is assigned into various kinds of cosmetics for curing freckles, spots on the skin of old man, pigmentation and acne.

Kojic acid can also eliminate free radical, strengthen cell activity of cell and keep the food fresh. It is widely used in the fields of medicine and food.