Potential antioxidant and anti-inflammatory properties in Teucrium salviastrum Schreb.

Abstract

Teucrium salviastrum Schreb. (Lamiaceae) is an endemic species from central and northern highlands of Portugal occurring usually in areas above 1.000m [1]. Teucrium spp. have been widely used as medicinal herbs and the biological activities of some species were already studied [2,3]. Here, for the first time, the phenolic composition of T. salviastrum extracts was determined, and their antioxidant and anti-inflammatory activities were assessed in vitro. Aerial parts of the plant were pulverized and extracted successively with dichloromethane, ethanol and 50% aqueous ethanol. Total phenols were determined by the Folin-Ciocalteu colorimetric method. Extracts were screened for their antioxidant activity using the 2,2′-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging method. The anti-inflammatory activity was assessed by the Griess method, evaluating the nitric oxide (NO) production, in the macrophage cell line Raw264.7 stimulated with lipopolysaccharide (LPS). HPLC-PDA-ESI/tandem MS was performed to obtain the phenolic profiles of the extracts. The DPPH method revealed that the ethanolic and hydro-alcoholic extracts are good free radical-scavengers. Additionally, these extracts inhibited LPS-induced macrophage NO production, a well known marker of the inflammatory processes. Relevant results were obtained for the ethanolic and hydro-alcoholic extracts, which showed, respectively, 0.175 and 0.095g of total phenols expressed in gallic acid equivalent/1g dry extract, which were, for most part, constituted by phenolic acid derivatives and a luteolin derivative. These results suggest that both ethanolic and hydro-alcoholic extracts of T. salviastrum have antioxidant and anti-inflammatory activities which could be related to the phenolic compounds and that the species has potential medicinal properties.