Kojic acid is a by-product in the fermentation process of malting rice for use in the manufacturing of sake, the Japanese rice wine. Research shows kojic acid to be effective for inhibiting melanin production.
Alpha Arbutin is derived from the leaves of bearberry, cranberry, mulberry or blueberry shrubs, and is also present in most types of pears. It has melanin-inhibiting properties. Alpha Arbutin and other plant extracts are considered safe alternatives to commonly used depigmenting agents to make the skin fairer. Medical studies have shown the efficiency of Alpha Arbutin for skin lightening.
In many parts of the world, licorice extract is used to treat hyperpigmentation, or the darkening of skin and nails due to high levels of melanin. Licorice extract is considered one of the many natural compounds, along with various types of citrus fruits, that act as a skin brightener when applied topically.
Vitamin C is an antioxidant that slows the rate of free-radical damage -- free radicals are unstable molecules that damage collagen and cause skin dryness, fine lines and wrinkles. Research suggests that vitamin C may reduce sunburn caused by exposure to ultraviolet B radiation and prevent the consequences of long-term sun exposure.
Azelaic acid is a component of grains, such as wheat, rye, and barley. It is applied topically in a cream formulation at a 20% concentration. Research shows that it is effective for skin discolorations and other research also indicates azelaic acid is a good option for inhibiting melanin production.