Excessive melanin biosynthesis leads to skin hyperpigmentation which causes undesirable skin appearance. Our previous studies have shown high tyrosinase inhibitory effect of Termilalia chebula fruits. In the present work, we aimed to separate anti tyrosinase fractions of T. chebula fruits. Total extract of T. chebula was prepared by maceration method with methanol 80% and evaporated in vacuum. Dried extract was partitioned successively with petroleum ether, chloroform, ethyl acetate and methanol. Further fractionation of active fraction (methanolic) was performed by liquid-liquid extraction (LLE) to give 18 fractions. Active fractions identified by bioautography and were subjected for colorimetry method in different concentrations using mushroom tyrosinase and L-tyrosine as substrate. The percentages of inhibition and IC50 values of each sample were determined. Fractions ІV and V separated in ethyl acetate-methanol by LLE method exhibited the greatest percentage of tyrosinase inhibition (80.52±1.8% and 76.81±2.1% respectively) in comparison to kojic acid (81.28±2.2%). The least IC50 values were also due to the fractions of ІV and V (IC50 values of 3.8 and 4.1 µg/ml respectively). Our findings indicated that the fractions of ІV and V have high anti tyrosinase effect which is compareable with kojic acid. Concidering the solvent of these fractions (methanol-ethyl acetate), they belongs to phenolic compounds. Further studies for separation of active compound have being carried out.
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