Antioxidant potential of Artemisia argentea L'Hér alcoholic extract and its relation with the phenolic composition

Artemisia argentea, known as losna or Madeira wormwood is used as aperitif drink with tonic effects. A reversed-phase high-performance liquid chromatography method (RP-HPLC) coupled with diode-array detection (DAD) and electrospray ionization mass spectrometry (ESI/MS) was used for the separation/characterization of phenolic compounds in A. argentea. A wide variety of components was found, mainly flavonoids (O- and C-glycosylated) and hydroxycinnamic acids derivatives. Five saponins, an uncommon type of compound in Artemisia species, were reported. Quantification of caffeoylquinic acids (CQA) was performed and 5-O-CQA and 3,5-O-diCQA were the major compounds (ca. 300 mg/100 g dried plant). Total phenolic content (TPC) and total flavonoid content (TFC) were established and four assays were used to measure the antioxidant capacity of the plant, revealing a high radical scavenging capacity and a weak reducing potential. Unlike other Artemisia subspecies, A. argentea is totally free of harmful components such as thujene, thujone or artemisia ketone.

Research highlights
► Characterization of phenolic compounds from A. argentea L'Hér by ESI(-)/MS.
► Five saponins were reported for the first time in Artemisia species.
► Characterization of three C-glycolysilated flavonoids.
► Four caffeoylquinic acids detected in A. argentea were quantified by HPLC-DAD.
► High radical scavenging capacity was found for A. argentea.