Antioxidant and xanthine oxidase inhibitory activity of Eucommia ulmoides Oliver leaf extracts.

The total phenolic content, flavonoid content, in vitro xanthine oxidase (XOD) inhibitory activity and antioxidant activity (AA) of Eucommia ulmoides Oliver leaf extracts were investigated. The AA investigations included 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, β-carotene/linoleic acid bleaching assay and oxygen radical absorbance capacity (ORAC) test. The ethyl acetate fraction (EE) showed the highest AA and xanthine oxidase inhibitory activity.