Essential oil composition and biological activity from <i>Artemisia caerulescens</i> subsp. <i>densiflora</i> (Viv.) Gamisans ex Kerguélen & Lambinon (Asteraceae), an endemic species in the habitat of La Maddalena Archipelago

<p>The purpose of this study was to investigate the composition of the essential oil obtained from a population of <i>Artemisia caerulescens</i> subsp. <i>densiflora</i> growing in Razzoli, an island in the La Maddalena Archipelago (Sardinia, Italy). <i>A. caerulescens</i> sups. <i>densiflora</i> Viv. (Asteraceae), a wild herb, seldom studied in the Mediterranean, represents one of the many rare endemic species growing in North Sardinia. The essential oil composition was analysed by means of GC/MS analysis, which showed davana ethers as the major volatile components, accounting together for 17.5%, followed by (E)-nerolidol (4.5%), <i>β</i>-oplopenone (3.3%), cis-sabinene hydrate (5.2%) and terpinen-4-ol (4.7%). The oil was tested for antioxidant activity by means of DPPH test, inhibition of lipid oxidation test and hypochlorous acid test, which showed a quite interesting scavenger capacity. For the first time, we reported the cytotoxic activity of the essential oil of <i>A. caerulescens</i> subsp. densiflora, against three human tumour cell lines (A375, MDA-MB231 and HCT116), with IC₅₀ values in the range 5.20–7.61 μg/mL, which deserved further studies to support its use as chemopreventive agent. Finally, the antimicrobial activity of the essential oil, displayed on a panel of human pathogens, was very low.</p> <p><i>Artemisia caerulescens</i> subsp. <i>densiflora</i> (Viv.) Gamisans ex Kerguélen & Lambinon (Asteraceae)</p