Evaluation of the Antihyperuricemic Activity of Phytochemicals fromDavallia formosanaby Enzyme Assay and Hyperuricemic Mice Model

Abstract

Abnormal serum urate levels are recognized as a critical factor in the progression of several chronic diseases. To evaluate the antihyperuricemic effect ofDavallia formosana, the inhibitory activities of 15 isolated phytochemicals, including five novel compounds of 6,8-dihydroxychromone-7-C-β-d-glucopyranoside (1), 6,8,3′,4′-tetrahydroxyflavanone-7-C-β-d-glucopyranoside (2), 6,8,4′-trihydroxyflavanone-7-C-β-d-glucopyranoside (3), 8-(2-pyrrolidinone-5-yl)-catechin-3-O-β-d-allopyranoside (4), and epiphyllocoumarin-3-O-β-d-allopyranoside (5), were examined against xanthine oxidase (XOD) and in a potassium oxonate-(PTO-) induced acute hyperuricemic mice model. The results indicated that compounds3and5significantly inhibited XOD activityin vitroand reduced serum uric acid levelsin vivo. This is the first report providing new insights into the antihyperuricemic activities of flavonoid glycosides which can possibly be developed into potential hypouricemic agents.