Chemical Composition, Acetylcholine Esterase and Anti-bacterial Activities of Essential Oils of Elaeosilenum thapsioides (Desf.) Maire from Algeria

Background: Traditionally, the Algerian medicinal plant Elaeosilenum thapsioides (Desf.) Maire has been used for many diseases. The present research work aims to explore the chemical and biological characterization of its essential oil. Methods: The essential oils were obtained by hydrodistillation of different Elaeosilenum thapsioides (Apiaceae) aerial parts samples collected from two different regions (Mahouane and Megres) from Setif, Eastern Algeria. The chemical characterization of the obtained essential oils is reported here for the first time. Besides, they were evaluated for their in vitro Acetylcholinesterase (AChE) inhibitory activity involved in Alzheimer’s disease using Ellman’s spectrophotometric method. Results: Additionally, their in vitro antimicrobial activity was assessed by the disc diffusion method. Both activities were performed at various oil concentrations. The GC/MS analysis of the essential oils from aerial parts (leaves, stems, flowers, and seeds) of E. thapsioides identified 47 constituents. Monoterpene hydrocarbons were the main components, ranging from 72.78 to 99.13%. Oxygenated monoterpenes and oxygenated sesquiterpenes ranged between 1.37 and 17.25% and 0.12 and 3.53% in essential oils from leaves and stems. Sesquiterpene hydrocarbons were present in small to large quantities in the essential oils of both populations, ranging from 0.69 to 13.44%. The presence of m-Methoxybenzyl isothiocyanate was recorded in stems essential oils from Mahouane and leaves essential oils from Merges, which was 9.73% and 3.72%, respectively. Conclusion: The stems essential oils obtained from plants collected in Mahouane showed the highest AChE inhibitory activity. The highest anti-bacterial activity was shown by the essential oil obtained from Megres leaves against Bacillus cereus ATCC 11778. The oils exhibited a moderate inhibitory activity in both tests.