Compositional Variation in Essential Oils of Wild Artemisia absinthium from Lithuania

Abstract

Chemical composition of essential oils (total thirty-six samples) of overground parts of Artemisia absinthium collected at twenty-five natural populations in Lithuania was investigated by GC and GC-MS. The first major component trans-sabinyl acetate (21.8–51.3 %) was determined in fourteen oils. As second main constituents were found β-pinene (7.2–12.9 %, 4 oils), sabinene (≤ 10.9 %, 2 samples), trans-sabinol (10.3 %, one oil), 1,8- cineole (6.2 %, one oil), epoxyocimenes (14.2 %, one sample) and (cis+trans) thujones (9.3–32.2 %, 5 oils) in the above oils. Other ten oils were characterised by a high amount of cis- and trans-thujone, which quantity was 18.0–71.7 %. As second major components were determined trans-sabinyl acetate (5.6–23 %, 8 oils), unknown compound (5.0 %, one oil) and β-pinene (9.9 %, one sample) in these oils. In another two oils major constituents were sabinene (≤ 23.4 %), sabinyl acetate (≤ 22.8 %), trans-sabinol (≤ 10.3 %) and linalool (≤ 12.2 ). One oil has a high percentage of cis-chrysanthenol (13.6 %), (3–pinene (12.5 %) and trans-chrysanthenyl acetate (11.6 %). However, differences in essential oil composition of separated plant organs (inflorescences and leaves) were elucidated in wormwoods from three various populations. Relative quantity of oxygenated monoterpenes, such as sabinol or sabinyl acetate is larger in leaves that in flowers. Compositional changes in essential oils of A. absinthium during different phenological stages were investigated. Monoterpene hydrocarbons fraction dominated in first leaves, while quantity of these compounds decreased in plant fruiting stage. Content of trans-sabinyl acetate significantly has changed, it was minor at leaves stage (0.8 %), while during fruiting amount of this constituent made up 52.6 % of total oil. Content of toxic thujones was the highest during flowering, this fact is very important in wormwood gathering, because the plant is widely use in phytotherapy and as a spice.