Flavonoid characterization and antioxidant activity of hydroalcoholic extracts from Achillea ligustica All.

Ethanolic extracts of Achillea ligustica All. (Asteraceae) flowering tops were evaluated. High-performance liquid chromatography-electrospray ionisation-mass spectrometry was used for the identification and quantification of phenolic compounds. 6-Hydroxykaempferol-3,6,4'-trimethyl ether, apigenin-6-C-glucoside-8-C-arabinoside, luteolin, and apigenin were the most abundant flavonoids. For the first time C-glycosylflavones were detected in A. ligustica with apigenin-6-C-glucoside-8-C-arabinoside being the most representative. The radical scavenging activity of the extracts was determined by DPPH test and ranged between 4.18 and 12.3 mM. The ability of these extracts to inhibit non-enzymatic lipid peroxidation was studied using the simple in vitro system of linoleic acid oxidation: five of the nine extracts exerted a protective effect at the lower amount tested (5 microg). Protection on CaCo-2 intestinal cells against TBH-induced toxicity was also investigated: the results showed that two of the extracts tested in this cell system had the ability to protect against oxidative stress induced by TBH starting from concentrations as low as 10 microg/ml.