Effect of environmental conditions on chemical polymorphism and biological activities among Artemisia absinthium L. essential oil provenances grown in Tunisia

• Wormwood essential oils originated from four Tunisian localities were studied.
• Essential oil yields and compositions vary significantly between the studied sites.
• Antioxidant activities vary significantly according to the studied localities.
• An antimicrobial activity was recorded against the all 10 tested strains.
• A significant effect of environmental factors is highlighted by this study.

Variation on yields, chemical composition and biological activities of essential oils of Artemisia absinthium L. collected from four different bioclimatic areas ranging from Humid to Arid stage of Tunisia was investigated. The observed yields of essential oils increase significantly from arid to humid climate. A significant qualitative and quantitative variation of the chemical composition according to the studied localities was revealed. Plants collected from the Inferior Arid bioclimatic region (Gafsa) presented chamazulene, α-thujone and camphor as the main components of their essential oils. However, for Superior Arid (Kasserine) and Semi Arid (El Kef) bioclimatic regions, camphor and chamazulene are the dominant constituents followed by linalool for Kasserine and bornyl acetate for El Kef originated oils. The Humid bioclimatic zone (Ghar Dimaou) showed different chemotype and presented camphor, (Z)-sabinene hydrate and 1-terpinen-4-ol as the major compounds. Based on the two DPPH and ABTS tests, the investigated oils highlighted important in vitro antioxidant capacities which increase significantly from the humid (Ghar Dimaou) to the Inferior Arid bioclimatic zone (Gasfa). Even the investigated essential oils displayed an antimicrobial activity against all the tested bacterial and fungal strains with variable degrees, our findings did not reveal a clear correlation between the antimicrobial properties and the studied bioclimatic zones.