Constituents of the stigmas of Crocus sativus and their tyrosinase inhibitory activity

Abstract

Four new compounds, crocusatins F (1), G (2), H (3), and I (4a), together with 21 known compounds, were isolated from an aqueous extract of the stigmas of Crocus sativus (saffron). The structures of 1-4 were established by spectral methods. The tyrosinase inhibitory activities of all 25 compounds isolated were evaluated in vitro using mushroom tyrosinase. Among them, crocusatin H (3), crocin-1 (5), and crocin-3 (6) showed significant tyrosinase inhibitory activity.