Analysis of Essential Oils of Artemisia absinthium L. from Lithuania by CC,GC(RI),GC-MS and 13 C NMR

Abstract

Different techniques have been utilized to determine the composition of Artemisia absinthum (wormwood) essential oil. The oil was fractionated on a silica gel column and each fraction analyzed by GC(RI), GC-MS and ¹³C NMR. This allowed the identification, for the first time in A. absinthium, of two diterpenes, 9-geranyl-p-cymene and 9-geranyl-α-terpinene, and two homoditerpenes, 9-(15,16-dihydro-15-methylene)-geranyl-p-cymene and 9-(15,16-dihydro-15-methylene)-geranyl-α-terpinene.

Chemical variability of A. absinthium essential oils from plants collected in the surroundings of Vilnius city over several years (1999-2007) was also shown. Chemical composition was determined by GC and GC-MS. Thujones (cis+trans, 10.2-36.3%) and trans-sabinyl acetate (9.8-39.2%) were the two predominant constituents of almost all the investigated oils (13 out of 15 samples). The third major compound was myrcene (5.1-9.2%, in four samples), β-pinene (5.4-10.4%, in 5), linalool (4.7% in one), trans-sabinol (6.4%, in one) and 1,8-cineole (5.2-7.1%, in two). In one oil, the prevailing components were thujones (cis+trans, 11.2%), trans-sabinene hydrate (11.0%) and trans-sabinyl acetate (8.8%), while another sample was characterized by a large quantity of trans-sabinyl acetate (55.2%) and the absence of thujones.