Prenylated flavonol glycosides from Epimedium grandiflorum: Cytotoxicity and evaluation against inflammation and metabolic disorder

Two new prenylated flavonol glycosides, epimedigrandiosides A and B (1 and 2), and 28 previously known compounds including prenylated flavonol derivatives, flavonol glycoside, megastigmanes, phenyl alkanoids, sesquiterpenoid glycoside, lignan, and hexene glucoside were isolated from the methanol extract of Epimedium grandiflorum. Structure elucidation was achieved by means of spectroscopic and spectrometric techniques including 1D and 2D NMR and HRESIMS. The absolute configuration of sugars was determined by chemical methods Structure elucidation of 3'-carbonyl-2-beta-L-quinovosyl icariin (19) was not previously described, so its H-1 and C-13 NMR data were reported for the first time. The methanol extract and the isolated compounds were evaluated for their activity towards several targets related to inflammation and metabolic disorder including NF-kappa B, iNOS, PPAR alpha and PPAR gamma. Moreover, their cytotoxic activity against four cancer cell lines (SK-MEL, KB, BT-549, SK-OV-3) and two noncancerous kidney cell lines (LLC-PK1 and Vero) were also evaluated.