Isolation of Chemical Constituents of Centaurea virgata Lam. and Xanthine Oxidase Inhibitory Activity of the Plant Extract and Compounds

Abstract

7-Hydroxyflavones (apigenin and hispidulin) exerted significant XO inhibitory effect with IC50 values of 0.99 ± 0.33 μM and 4.88 ± 1.21 μM, respectively. Therefore, these compounds are responsible for the XO-inhibitory effect of the extract. The free radical scavenging activity of the isolated flavonoids was determined by DPPH assay, and it was stated that none of the compounds have substantial antioxidant activity, therefore the reduced generation of reactive oxygen species may be the consequence only of XO inhibition.