Artemisia arborescens Essential Oil Composition, Enantiomeric Distribution, and Antimicrobial Activity from Different Wild Populations from the Mediterranean Area

Abstract

Aerial parts of Artemisia arborescens were collected from different sites of the Mediterranean area (southwestern Algeria and southern Italy) and the chemical composition of their essential oil (EO) extracted by hydrodistillation was studied by both gas chromatography (GC) equipped with an enantioselective capillary column and GC/mass spectrometry (GC/MS). The EOs obtained were tested against several Listeria monocytogenes strains. Using GC and GC/MS, 41 compounds were identified, accounting for 96.0 -98.8% of the total EO. All EOs showed a similar terpene profile, which was rich in chamazulene, b-thujone, and camphor. However, the concentration of such compounds varied among the EOs. A. arborescens EO inhibited up to 83.3% of the L. monocytogenes strains, but the inhibitory spectrum varied among the EOs, with those from Algeria showing a higher inhibition degree than the Italian EOs. Such effect likely depended on the ketone (b-thujone + camphor) content of the EO. The differences in the EO composition support the hypothesis that A. arborescens has at least two different chemotypes: a b-thujone and a chamazulene type. The EO inhibitory spectrum indicates the A. arborescens EO as a valuable option in the control of the food-borne pathogens.

Chamazulene-Rich Artemisia arborescens Essential Oils Affect the Cell Growth of Human Melanoma Cells

“…Thujone isomers occur in nature as a mixture of α-and β-thujone, and typically the β-thujone isomer has been identified in A. arborescens oils of different geographical origins as the most abundant, ranging from 0.17% to 68.9%, while α-thujone is often contained in traces or below 1% [9]. α-Thujone is a psychotropic and convulsant substance, so thujones have represented, in the past, a controversial topic of discussion relativeto the psychoactive effects of the liquor absinth (obtained from A. absinthium), initially The first chemotype (Chemo I), the most common, was also reported for plants from Tunisia, Sardinia and island of Crete, southern Greece, South Italy and in Turkey [7,23,24], the North-western area of Sicily and in Messina [3,11], Algeria and southern Italy (Sicily: Capo Zafferano and Termini Imerese) [14]. The chemotype β-thujone/chamazulene (Chemo II), free of camphor, was found for A. arborescens essential oil recorded in Algeria, Sardinia and Lebanon [13,24].…”

“…It is well-known that the quali/quantitative composition of A. arborescens EO is strongly affected by the stage of plant development, environmental factors and geographic origin [9]. For instance, Said et al [14] found that monoterpenes were higher and sesquiterpenes lower in the EO coming from the relatively arid (Algeria) than the relatively humid (Italy) environments, and their hypothesis was that the accumulation of monoterpenes could be derived from the oxidation of the sesquiterpene fraction as a response of the plant to the oxidative conditions. Militello et al [6] observed an increase in the monoterpene fraction as plants pass from vegetative to the flowering stage while in the samples studied by Ornano et al [13] the highest content of chamazulene is reached in summer (July, as confirmed by Michelakis et al [7]), while that of β-thujone in spring (May), and generally the EO from plant material collected in July showed the highest amount of sesquiterpene hydrocarbons, while that collected in May exhibited the highest content of oxygenated monoterpenes.…”

“…The use of A. arborescens EO is also common in flavoring and fragrance due to its fresh, slightly sweet, minty, woody and earthy scent [9]. Besides, the EO showed in vitro antipyretic, anti-inflammatory, antioxidant, antiangiogenic, antiviral and antimicrobial activities [3,4,6,[10][11][12][13][14], with different effects based on the main compounds found in the essential oil. Indeed, the composition of A. arborescens EOs was found to be very variable depending on the environment [5,14].…”

“…Besides, the EO showed in vitro antipyretic, anti-inflammatory, antioxidant, antiangiogenic, antiviral and antimicrobial activities [3,4,6,[10][11][12][13][14], with different effects based on the main compounds found in the essential oil. Indeed, the composition of A. arborescens EOs was found to be very variable depending on the environment [5,14]. Basically, the literature describes two chemical profiles for a group of compounds of particular interest such as camphor, chamazulene and thujones: the first one shows high levels of camphor and chamazulene whereas the second one is rich in β-thujone [6].…”

Acute toxicity and central and peripheral analgesic activity of flowers and leaves essential oils of Asteriscus graveolens from South-West Algeria

“…1 . This plant family is known for its use as a remedy in traditional medicine 2,3 . A. graveolens is known under the vernacular name "Taffs" and is one of the endemic medicinal plants, widely used by the local population in south-western Algeria 4 .…”