One new and six known flavone glycosides were isolated from the MeOH extract of Melilotus neapolitana Ten. The new compound, identified as 7-O-β-D-glucopyranosyloxy-4′,5-dihydroxy-3-[O-α-L- rhamnopyranosyl-(1→6)-3-O-β-D-glucopyranosyloxy] flavone (1) by 1D and 2D NMR techniques and mass spectra, was isolated along with kaempferol-3-O-rutinoside (2), kaempferol-3-O-glucoside (3), rutin (4), quercetin-3-O-glucoside (5), isorhamnetin-3-O-rutinoside (6), and isorhamnetin-3-O-glucoside (7). The antioxidant and radical scavenging activities of these compounds and the whole crude methanol extract were evaluated. The organic extract can inhibit MDA marker's synthesis by 57%. All the metabolites displayed good reducing power, with the kaempferol (2,3) and isorhamnetin derivatives (6,7) being less active than the corresponding quercetin derivatives 4,5. © 2007 by MDPI.
Reactive oxygen species scavenging activity of flavone glycosides from Melilotus neapolitana
FIORENTINO, Antonio;D'ABROSCA, Brigida;PACIFICO, Severina;MONACO, Pietro
2007
Abstract
One new and six known flavone glycosides were isolated from the MeOH extract of Melilotus neapolitana Ten. The new compound, identified as 7-O-β-D-glucopyranosyloxy-4′,5-dihydroxy-3-[O-α-L- rhamnopyranosyl-(1→6)-3-O-β-D-glucopyranosyloxy] flavone (1) by 1D and 2D NMR techniques and mass spectra, was isolated along with kaempferol-3-O-rutinoside (2), kaempferol-3-O-glucoside (3), rutin (4), quercetin-3-O-glucoside (5), isorhamnetin-3-O-rutinoside (6), and isorhamnetin-3-O-glucoside (7). The antioxidant and radical scavenging activities of these compounds and the whole crude methanol extract were evaluated. The organic extract can inhibit MDA marker's synthesis by 57%. All the metabolites displayed good reducing power, with the kaempferol (2,3) and isorhamnetin derivatives (6,7) being less active than the corresponding quercetin derivatives 4,5. © 2007 by MDPI.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
