Soluble epoxide hydrolase inhibitory activity of phenolic glycosides from Polygala tenuifolia and in silico approach

The goal of this study was to identify soluble epoxide hydrolase (sEH) inhibitors from plants. Our efforts led to the isolation of nine phenolic glycosides 1–9 from the roots of Polygala tenuifolia Willd. The structures of compounds were determined by spectroscopic methods, including mass spectroscopy and one-dimensional and two-dimensional nuclear magnetic resonance, and compared with published data. All the isolated compounds were evaluated for their inhibitory activity against sEH. The IC₅₀ values for inhibition ranged 6.4 ± 0.4 to 27.2 ± 0.3 µM. Inhibitors 2–9 were confirmed the interaction with receptor as competitive type. Molecular docking demonstrated that inhibitors 2–9 could bind sufficiently to the right pocket. Additionally, potential inhibitors (5, 6, and 8) were confirmed to show the flexible movement with the protein in these sites of receptor.