Essential oil composition and variability of Artemisia herba-alba Asso. growing in Tunisia: comparison and chemometric investigation of different plant organs.

ABSTRACT

This study was conceived to investigate the composition of four essential oils (EOs) extracted by hydrodistillation from four parts (leaves, stems, leaves/stems, roots) of Artemisia herba-alba growing wild in the Center of Tunisia. For this, Artemisia herba-alba aerial and roots parts were shade dried with ventilation at room temperature. Then, plant different parts were cut into small pieces and subjected to hydrodistillation using a Clevenger-type apparatus. The gas chromatography (GC) analyses were accomplished with a HP-5890 Series II instrument. The main results showed a total of 152 compounds detected and identified by GC and GC-MS and accounting for 91.3-99.7% of the whole oil. The four oils were characterized by the predominance of monoterpene derivatives (68.2-99.5%) and the major volatile constituent was α-thujone (18.2-45.5%). Qualitative and quantitative differences between the four essential oils have been noted for some compounds. The main compounds of leaves essential oil were α-Thujone (45.5%), β-Thujone (11.4%), trans-sabinyl acetate (10.1%), 1,8-Cineole (7.4%) and camphor (6.8%). α-Thujone (27.5%) was also the main compound in the essential oil of leaves/stems, followed by camphor (22.9%), 1,8-cineole (8.3%), β-thujone (8.2%) and camphene (5.6%). The essential oil of stems was dominated by α-Thujone (28%) followed by β-Thujone (11.4%) and chrysantenone (11%). In the essential oil of roots, α-thujone was less represented (18.2%), followed by camphor (14.6%) and curcumen-15-al (14.3%). It is important to mention that curcumen-15-al has been reported for the first time in Artemisia herba-alba oil Our results revealed avariability in the chemical composition and the yield of the EOs from Artemisia herba-alba. Moreover, curcumen-15-al is a new chemotype first found in Artemisia herba-alba from Tunisia.