Abstract

INVITRO EVALUATION OF VARNYA KARMA (ANTI-TYROSINASE ACTIVITY) OF VARAHI KANDA (DIOSCOREA BULBIFERA LINN.)

Dr. Akshaya B.*, Dr. Dharani and Dr. Arpitha C. Rao

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Abstract

Pigmentation disorders are very commonly seen in cosmetology. Over activity of melanin is responsible for hyperpigmentation. Tyrosinase enzyme plays an important role in the biosynthesis of melanin. Therefore tyrosinase inhibitors are used as depigmentation agents. Currently used synthetic tyrosinase inhibitors are known to have some drawbacks. There is a need for safe and effective herbal drug with tyrosinase inhibition property (antityrosinase activity) to tackle this problem. The present study was taken up to evaluate the antiyrosinase activity (varnya karma) of Varahikanda (Dioscorea bulbifera Linn.) Different concentrations of aqueous, ethanolic extract of varahikanda and kojic acid was tested for invitro antityrosinase activity using mushroom tyrosinase inhibition assay. In this study kojic acid was taken as standard. Standard and test drugs showed dose dependent inhibition of tyrosinase in tested concentrations. Standard drug kojic acid showed inhibition with IC50 54.08 μg/ml. Aqueous extract of varahikanda showed inhibition with IC50 302.06μg/ml and ethanolic extract showed inhibition with IC50 - 608.40μg/ml. Kojic acid being pure and synthetic compound showed better inhibition. Varahikanda is a mixture of many chemical constituents and showed more IC50 value compared to that of kojic acid. Ushna veerya, tikta rasa, deepana, rasayana karmas, presence of phenols, flavonoids and antioxidant properties may contribute to varnya karma (antityrosinase activity) of varahikanda.

Keywords: Varahikanda, Kojic acid, Varnya, Tyrosinase inhibitor, Mushroom tyrosinse assay.