Inhibitory Activity on Xanthine Oxidase and Antioxidant Properties of Teucrium polium

Abstract

The antioxidative activities of subfractions; methanol (CE), chloroform (CHE) and ethyl acetate (EAE) of Teucrium polium extracts (TPE) were investigated. HPLC analysis of the plant revealed the existence of procyanidins B 1 and B 2 , gallic acid, catechin and epicatechin. All the extracts showed inhibitory properties on xanthine oxidase, with IC 50 rang-ing from 0.80 ± 0.07 to 11.76 ± 0.50 µM/quercetin equivalent. In the cellular system, all the extracts showed a protec-tive effect greater than those of quercetin, rutin and gallic acid against t-BHP induced oxidative damages in human erythrocytes. These results were clearly confirmed by a modified thiobarbituric acid-reactive species (TBARS), and β-carotene/linoleic acid assay which demonstrated that CHE possess an inhibition ratio of the linoleic acid oxidation (83.11%) close to that of BHT (96.77%). In addition, the results showed that the extracts possess a potent DPPH radical scavenging activity and gave a reduction power greater than rutin, quercetin, gallic acid and ascorbic acid in FRAP as-say. These results show that Teucrium polium extracts have strong antioxidant effects and may have some clinical bene-fits.