Table 2.
The main chemical constituents of essential oils or their fractions studied in this work.
| Compound | LRIs (DB-5MS Column) | LaCi | LaCif | LaCaf1 | LaCaf2 | LoP | LoC | LoT | LoTf | LoTC | TdS1 | TdS2 | PaS1 | ObS1 | VcS1 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Exp. | Lit. | |||||||||||||||
| α-Pinene * | 935 | 932 a | 0.3 | 0.2 | 0.2 | - | 1.7 | 0.4 | - | - | 0.4 | - | - | 4.6 | 0.5 | 9.4 |
| α-Phellandrene | 1005 | 1002 a | 0.1 | - | - | - | 7.1 | - | - | - | 0.5 | - | - | 4.4 | - | - |
| p-Cymene * | 1027 | 1024 a | - | - | - | - | 12.6 | 14.4 | 2.3 | 2.0 | 19.1 | 3.0 | 3.6 | 3.0 | - | - |
| Limonene * | 1034 | 1029 a | 2.4 | 5.9 | 82.2 | 0.9 | 2.1 | 0.3 | - | - | 0.9 | - | - | 6.0 | - | 0.8 |
| 1,8-Cineol * | 1036 | 1031 a | - | - | - | - | 13.0 | 1.3 | - | - | - | - | - | 3.6 | 8.1 | 0.8 |
| γ-Terpinene | 1061 | 1059 a | - | - | - | - | 2.4 | 5.3 | 0.9 | 6.9 | 9.2 | 0.6 | 0.7 | 0.8 | - | - |
| Linalool * | 1099 | 1096 a | 1.1 | 2.5 | 0.4 | 0.5 | 0.7 | 1.0 | - | - | 0.3 | - | - | 0.4 | 42.7 | - |
| Estragole * | 1203 | 1196 a | - | - | - | - | - | - | - | - | - | - | - | - | 18.6 | - |
| Neral * | 1246 | 1252 b | 11.9 | 18.1 | - | - | - | - | - | - | - | - | - | - | - | - |
| Carvone * | 1259 | 1258 c | - | - | 12.2 | 78.2 | - | - | - | - | - | - | - | - | - | - |
| Geraniol * | 1260 | 1240 b | 19 | 8.1 | - | - | - | - | - | - | - | - | - | - | - | - |
| Piperitone | 1265 | 1264 c | - | - | - | 4.8 | - | - | - | - | - | - | - | 14.8 | - | - |
| Geranial * | 1272 | 1270 b | 24.5 | 24.8 | - | - | - | - | - | - | - | - | - | - | - | - |
| Thymol * | 1290 | 1290 a | - | - | - | - | 14.0 | 8.0 | 75.3 | 82.9 | 49.4 | - | 0.2 | - | - | - |
| Carvacrol * | 1300 | 1298 a | - | - | - | - | 0.9 | 35 | 4.9 | 1.2 | 2.7 | - | 0.4 | - | - | - |
| Piperitenone | 1347 | 1343 a | - | - | 0.3 | 0.3 | - | - | - | - | - | - | - | 14.8 | - | - |
| α-Copaene | 1385 | 1376 a | - | - | - | 0.3 | 0.6 | 0.7 | - | - | - | - | - | 2.9 | - | 7.0 |
| trans-β-Caryophyllene * | 1433 | 1427 c | 9.1 | 13.3 | - | 0.1 | 15.1 | 4.4 | 5.4 | 7.0 | 1.6 | 4.0 | 4.9 | 7.4 | 0.9 | 19.2 |
| α-Humulene * | 1467 | 1468 c | 2.8 | 2.8 | - | - | 8.1 | 1.1 | 3.2 | - | 0.9 | - | 0.4 | 1.5 | 2.5 | 2.7 |
| Aristolochene | 1483 | 1488 a | - | - | - | - | - | - | - | - | - | 17.9 | 20.9 | - | - | - |
| Germacrene D | 1492 | 1481 a | 4.3 | 1.5 | 0.1 | - | 0.9 | - | - | - | - | - | - | 1.7 | 4.9 | 12.3 |
| β-Selinene | 1502 | 1490 a | - | - | - | - | 0.5 | 0.3 | - | - | - | 5.2 | 5.8 | - | - | - |
| Valencene | 1503 | 1496 a | - | - | - | - | - | - | - | - | - | 7.4 | 6.5 | 1.2 | - | - |
| trans-β-Guaiene | 1517 | 1502 a | 2.2 | - | - | - | - | - | - | - | - | - | - | - | - | 11.8 |
| Dehydrofukinone | 1827 | 1820 c | - | - | - | - | - | - | - | - | - | 25.4 | 19.3 | - | - | - |
LRIs, linear retention indices calculated using n-alkanes C8–C25 mixture on the DB-5MS (non-polar) column. L. alba: neat EO (LaCif) and light fraction (LaCif) of citral chemotype; and limonene-rich fraction (LaCaf1) and carvone-rich fraction (LaCaf2) of carvone chemotype. L. origanoides: neat EO of phellandrene chemotype EO (LoP), carvacrol (LoC), thymol-carvacrol (LoTC), and thymol (LoT) chemotypes; and thymol-rich fraction (LoTf) of the thymol chemotype. Neat EOs of T. diffusa collected in 2019 (TdS1) and in 2016 (TdS2). Neat EOs of O. basilicum (ObS1), P. aduncum (PaS1) and V. curassavica (VcS1). Exp. Experimental. Lit. Literature a Adams, 2007 [26]; b Babushok et al., 2011 [27]; c NIST 2017 [28]. * Standard compounds were used for confirmatory identification.