Xanthine oxidase inhibitors from Archidendron clypearia (Jack.) I.C. Nielsen: Results from systematic screening of Vietnamese medicinal plants

ABSTRACT

Objective To screen Vietnamese medicinal plants for xanthine oxidase (XO) inhibitory activity and to isolate XO inhibitor(s) from the most active plant. Methods The plants materials were extracted by methanol. The active plant materials were fractionated using different organic solvents, including n-hexane, ethyl acetate, and n-butanol. Bioassay-guided fractionation and column chromatography were used to isolate compounds. The compounds structures were elucidated by analysis of spectroscopic data, including IR, MS, and NMR. Results Three hundreds and eleven methanol extracts (CME) belonging to 301 Vietnamese herbs were screened for XO inhibitory activity. Among these plants, 57 extracts displayed XO inhibitory activity at 100 μg/mL with inhibition rates of over 50%. The extracts of Archidendron clypearia (A. clypearia), Smilax poilanei, Linociera ramiflora and Passiflora foetida exhibited the greatest potency with IC