Chemical composition and biological activities of a new essential oil chemotype of Tunisian Artemisia herba alba Asso

The aim of the present study was to investigate the chemical composition, antioxidant, angiotensin I-converting enzyme (ACE) inhibitory, antibacterial and antifungal activities of the essential oil of Artemisia herba alba Asso (Aha), a traditional medicinal plant widely growing in Tunisia. The essential oil from the air dried leaves and flowers of Aha were extracted by hydrodistillation and analyzed by GC and GC/MS. More than fifty compounds, out of which 48 were identified. The main chemical class of the oil was represented by oxygenated monoterpenes (50.53%). These were represented by 21 derivatives, among which the cis-chrysantenyl acetate (10.60%), the sabinyl acetate (9.13%) and the alpha-thujone (8.73%) were the principal compounds. Oxygenated sesquiterpenes, particularly arbusculones were identified in the essential oil at relatively high rates. The Aha essential oil was found to have an interesting antioxidant activity as evaluated by the 2,2-diphenyl-1-picrylhydrazyl and the beta-carotene bleaching methods. The Aha essential oil also exhibited an inhibitory activity towards the ACE. The antimicrobial activities of Aha essential oil was evaluated against six bacterial strains and three fungal strains by the agar diffusion method and by determining the inhibition zone. The inhibition zones were in the range of 8-51 mm. The essential oil exhibited a strong growth inhibitory activity on all the studied fungi. Our findings demonstrated that Aha growing wild in South-Western of Tunisia seems to be a new chemotype and its essential oil might be a natural potential source for food preservation and for further investigation by developing new bioactive substances.