Santin

The following solvents were used in the present study: 99.9% acetonitrile, 99.9% methanol, obtained from Sigma-Aldrich (Steinheim, Germany) and 99.8% trifluoroacetic acid supplied from Merck (Darmstadt, Germany). The water was purified using a Millipore Milli-Q apparatus. Analytical and HPLC grade substances: potassium persulphate, 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), caffeic, neochlorogenic, chlorogenic, 4-caffeoylquinic, 3,4-dicaffeoylquinic, 3,5-dicaffeoylquinic, 1,5-dicaffeoylquinic, and 4,5-dicaffeoylquinic acids, rutin, quercitrin, quercetin, isoquercitrin, luteolin-7-glucoside, luteolin-7-rutinoside, luteolin-3,7-diglucoside, apigenin-7-glucoside, and santin were obtained from Sigma-Aldrich; luteolin from Roth GmbH (Karlsruhe, Germany); trolox and apigenin from Fluka Chemika (Buchs, Switzerland).

Analytical and HPLC grade solvents and reagents were used for chemical analyses. Acetonitrile (99.9%) and methanol (99.9%)as well as the references as quercetin, quercetin-3-O-glucoside, luteolin-7-O-glucoside, luteolin-7-O-rutinoside, rutin trihydrate, apigenin-7-O-glucoside, santin, 3-O-caffeoylquinic acid, 5-O-caffeoylquinic acid, 4-O-caffeoylquinic acid, 1,3-O-dicaffeoylquinic acid, 3,4-O-dicaffeoylquinic acid, 3,5-O-dicaffeoylquinic acid, 1,5-O-dicaffeoylquinic acid, and 4,5-O-dicaffeoylquinic acid, were obtained from Sigma-Aldrich (Steinheim, Germany); trifluoroacetic acid (≥99%) and apigenin were supplied from Fluka Chemika (Buchs, Switzerland). The purified deionized water (18.2 mΩ/cm) was produced using the Millipore Simpak1 Synergy 185 ultra-pure (Bedford, MA, USA) water system.