Coumarin and Moracin Derivatives from Mulberry Leaves (Morus albaL.) with Soluble Epoxide Hydrolase Inhibitory Activity

This study identified three coumarins (1-3), and six moracin derivatives (4-9). The structures of these natural compounds were determined by the spectroscopic methods, including 1D and 2D NMR methods, and comparison with previous reported data. All of the isolated compounds were assessed for the effects on the soluble epoxide hydrolase (sEH) inhibitory activity. Among them, compounds1-7exhibited significant inhibitory effect with 100% inhibitory, with IC(50)values of 6.9, 0.2, 15.9, 1.1, 1.2, 9.9, and 7.7 mu M, respectively. A kinetic study revealed that compounds1-4, and6were competitive types of inhibitors, compounds5and7were mixed types of inhibitors. These results suggest that moracin and coumarin derivatives from mulberry leaves are significant sEH inhibitors.