Antioxidant and Anti-Tyrosinase Activity of Some Medicinal Plants

Exposure to UV radiation becomes inevitable these days due to the depletion of ozone layer. Skin being the largest and outermost organ of the body, gets much exposed as well as affected due to these radiation. The absorption of high energy UV radiation by the cells results in the liberation of free radicals. The formed free radicals damage the major macromolecules like proteins, lipids and DNA through its chain reaction mechanism. Free radicals' being the signal transducers of the cells promotes or enhances the expression of the enzyme tyrosinase. Tyrosinase, the key enzyme in melanogenesis promotes the biosynthesis of melanin. The melanin formed is an endogenous antioxidant produced in the cell to protect itself from the free radical toxicity. Due to over exposure to UV radiation or the improper trigger in the biogenesis of melanin results in the hyperpigmentation disorders. Hence finding the inhibitor for tyrosinase becomes a key target for the cosmetic industries. Thus the present study opts for searching such novel tyrosinase inhibitor from herbal origin, which can attenuate the free radical toxicity by being a potent antioxidant.