Phenolic compounds and antioxidant activity of Achillea macrophylla L. and Achillea stricta Schleicher from Valsesia (Italy)

Valsesia is an area of Western Italian Alps characterized by the presence of many species of wild and autochthonous plants. Some of these plants are commonly used by local population for pharmaceutical purposes and human nourishment, in veterinary medicine. In this work we present the results obtained by analysis of methanolic extracts and their fractions of two species belonging to the Achillea genus (A. macrophylla L. and A. stricta Schleicher) collected in Valsesia. These species have shown significant antioxidant activity and aim of this work is therefore the identification of pure compounds responsible of this activity. The MeOH extracts have been separated with Sephadex LH-20; 22 and 19 fractions have been obtained from A. macrophylla and A. stricta respectively. The fractions with different TLC profiles were tested for the antioxidant activity, evaluated as removal of the stable radical DPPH, total antioxidant capacity based upon the reduction of Cu++ to Cu+ and lipid peroxidation. Subsequently we have separated the selected fractions with HPLC: 4 active compounds were isolated (Chlorogenic acid isomers, Rutin, Luteolin-7-O-glucoside, Apigenin-7-O-glucoside).