Antioxidative properties of Cardoon (Cynara cardunculus L.) infusion against superoxide radical, hydroxyl radical, and hypochlorous acid

Polyphenols are able to act as antipxidants by virtue of their hydrogpn-donating and metal-chelating capacities. Cardoon (Cynara cardunculus L.) is a species containing. considerable amounts of polyphenolic compounds, namely flavonoids and phenolic acids. This study examined the antioxidant activity. of cardoon lyophilized infusion against superoxide radical, hydroxyl radical, and hypochlorous acid. Superoxide radical Was generated either in an enzymatic system or nonenzymatically, and the scavenging ability was assessed by the inhibition of superoxide radical-induced reduction of nitroblue tretrazolium. Hydroxyl radical was generated by the Fe3+-EDTA/ascorbate Fenton system, and scavenging capacity was estimated by evaluating the inhibition of, hydroxyl radical-induced deoxyribose degradation into thiobarbituric acid-reactive substances. Inhibition of hypochlorous, acid-induced 5-thio-2-nitrobenzoic acid oxidation to 5,5'-dithiobis(2-nitrobenzoic acid) was used in order to test the hypochlorous acid scavenging activity.