Flavonoid constituents of Carduncellus mareoticus (Del.) Hanelt and their biological activities

Abstract

The total ethanolic extract (TEE) of Carduncellus mareoticus (Del.) Hanelt showed antioxidant and antihyperlipidemic activities, which were attributed to the ethyl acetate fraction (EAF). Also TEE showed potent cytotoxic activity against a cervix cancer cell line (IC50 = 5 μg/mL) and moderate activity against a breast cancer cell line. Chemical investigation of EAF led to the isolation of a new flavonoid, 8-hydroxy-5-methoxyluteolin 7-O-β-D-glucopyranoside (11), along with ten known metabolites (1-10). Three of these compounds, isorhamnetin 3-O-β-D-glucopyranoside (7), luteolin 3′-O-β-D-glucopyranoside (8), and eriodictyol 7-O-β-D-glucopyranoside (9) are reported for the first time from the genus Carduncellus, and two compounds, chrysoeriol 7-O-β-D-glucopyranoside (6), and luteolin 7-O-β-D-glucopyranoside (10), for the first time from C. mareoticus. The rest of the isolated compounds, chrysoeriol (1), luteolin (2), quercetin (3), kaempferol 3-O-α-L-arabinopyranoside (4), and kaempferol 3-O-β-D-glucopyranoside (5) have been previously reported from the genus.