Tyrosinase Inhibitory Properties of Compounds Isolated from Roots.

A comprehensive phytochemical investigation of root extract led to the isolation of two new geranylated xanthones ( and ), one new geranylated flavone (), one new flavanone (), and one unique benzopyran (), along with 16 known compounds. Structures of the new compounds were elucidated by a combination of spectroscopic and computational methods. Two different types of compounds, flavone and arylbenzofuran , displayed the most potent antityrosinase activity with IC values of 1.7 ± 0.2 and 1.2 ± 0.1 μM, respectively. In addition, kinetic measurements and molecular docking simulations of compounds and were performed and revealed that compound is a competitive inhibitor binding with the tyrosinase active site, while compound is a noncompetitive tyrosinase inhibitor binding the enzyme at the allosteric site.