Antioxidant activity of phenolic and phenylethanoid glycosides from Teucrium polium L

Fractionation of methanol extract obtained from the aerial parts of T. polium yielded one new phenylethanoid glycoside, named poliumoside B, together with four known flavonoids, two iridoid glycosides and a known poliumoside. The structures of all of these compounds were elucidated on the basis of spectroscopic data from 1D and 2D NMR experiments and MS spectral analyses. The antioxidant activities of the crude extracts and of the isolated compounds were evaluated through tests such as DPPH radical scavenging capability, reducing power, xanthine oxidase inhibitory effect and inhibition of linoleic acid peroxidation.