The aerial parts (~20 cm, 15-100 g) of A. campestris L. from ten different wild populations of Lithuania were gathered at the full flowering stage. Plant material was dried at room temperature (20-25 ℃). Oils (samples 1-10) obtained from Artemisia campestris plants collected at sampling sites (A-I,Y) characterized by locality, city (c.) or district (d.), soil type (Or, ordo; Sn, sand; Sl, sandy loam; Gr, gravel; Lm, loam) and description of natural habitat (Af, abandoned field; Fe, forest edge; Ct, cutting area; Mw, meadow; Rs, roadside; Rv, river valley): A (1) Birstonas c. (Or, Ct); B (2) Palanga c. (Sn, Fe); C (3) Nociunai, Kedainai d. (Or, Mw); D (4) Alytus c. (Sl, Rs); E (5) Moletai c. (Lm, Af); F (6) Kaltanenai, Sencionys d. (Gr, Fe); G (7) Merkine, Alytus d. (Sl, Ct); H (8) Trakai c. (Gr, Af); I (9) Druskininkai c. (Or, Rv); Y (10) Vilnius c. (Gr, Af).

The main chemical profile (ten samples) was characterized by the predominance of germacrene D (9.8-31.2%), while spathulenol, humulene epoxide II and caryophyllene oxide were found as the first major compounds in another three oils. One oil was determined as a mixed chemotype. Some compounds such as gamma-curcumene, alpha-cadinol, (E,E)-alpha-farnesene, beta-ylangene, beta-selinene and humulene epoxide II have been mentioned for the first time among three principal constituents in A. campestris oils. The fifty-six components made up 73.6.1-98.5% of the total content, while the remaining twenty-six volatile compounds were identified in insignificant amounts in the A. campestris essential oils.

Hyptis marrubioides were collected in March 2003 at the mature vegetative stage from their natural habitat; 20 randomised individual plants at the same age representing the local population were collected as homogenous samples from each locality: (A) Lavras (21° 14′ S/44° 59′ W), at an altitude of 919 m; (B) Tiradentes (21° 6′ S/44° 10 m W), 927 m.

The results were submitted to Principal Component and Cluster analysis which allowed three groups of oils to be distinguished with respect to sampling site and post-harvested process: cluster I (fresh leaves and fresh or dried stems from Lavras site) with high percentage of caryophylla-4(14),8(15)-dien-5beta-ol (16.7%) and eudesma-4(15),7-dien-1beta-ol (12.8%); cluster II (dried leaves and stems from Tiradentes site) with epi-longipinanol (16.2%) rich oil, and cluster III (dried leaves from Lavras) containing a high content of beta-caryophyllene (17.4%) and alpha-copaene (10.1%). Canonical discriminant analysis showed that is possible to accurately predict 100% well-classification in the original clusters using beta-caryophyllene, epi-longipinanol and caryophylla-4(14),8(15)-dien-5beta-ol as predictor variables. The whole or sliced plant materials resulted in similar chemical composition.

The aerial parts of T. chamaedrys were collected at the flowering stage in June 2004 near Corti, Corsica, France and near Oristano, Sardinia, Italy

The Corsican and Sardinian oils of T. chamaedrys investigated in this study were qualitatively similar but they differed by the amount of their major components. The major components were beta-caryophyllene (29.0% and 27.4%, respectively) and germacrene D (19.4% and 13.5%, respectively), followed by alpha-humulene (6.8%) and delta-cadinene (5.4%) in the Corsican oil and by caryophyllene oxide (12.3%) and alpha-humulene (6.5%) in the Sardinian oil. These quantitative differences are also noticeable on the amounts of the different class compounds. Especially, the monoterpene hydrocarbons amounted for 10.3% and 4.1% in Sardinian and Corsican oils respectively and the oxygenated sesquiterpenes amounted for 18.9% and only 7.4% in both oils, respectively. Both oils were qualitatively rather similar in comparison with those reported in the literature from various geographic regions. However, among the 87 components identified in this study, 47 minor components (< 0.6%) reported were identified for the first time in T. chamaedrys oil. This study confirms the quantitative variability of the major components according to the plant origin.