Antioxidant properties and total phenolic content of eight Salvia species from Turkey

Methanolic extracts of eight Salvia species, namely S. aethiopis, S. candidissima, S. limbata, S. microstegia, S. nemorosa, S. pachystachys, S. verticillata, and S. virgata, sampled from Eastern Anatolia in Turkey, were screened for their possible antioxidant activities by two complementary test systems, namely DPPH free radical scavenging and beta-carotene/linoleic acid. Total phenolic content of the extracts of Salvia species were performed Folin-Ciocalteu reagent and gallic acid used as standard. A wide variation has been observed among species in terms of antioxidant activity and total phenolic content. In both DPPH and beta-carotene system, the most active plant was Salvia verticillata with a value of IC50=18.3 microg/ml and 75.8%, respectively. This species also has the highest total phenolic content (167.1 mgGAE/g DW). The total amount of phenolics was between 50.3 to 167.1 mgGAE/g DW among species. A positive linear correlation was observed between total phenolic content and antioxidant activity of the extracts. The results suggest that the extract of Salvia species, notably Salvia verticillata with the highest antioxidant activity, can be used as natural antioxidants in the food industry.