Table 1.
Effects of different drying methods on the essential oil composition of Origanum vulgare. Results are expressed as mean percentage ± standard deviation of three independent determinations.
| Rt | Compound | Fresh | CONV1 | CONV2 | MW1 | MW2 | MW3 | OT | KIa | KIb | Ident.c |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 12.548 | α-Pinene | 2.1 ± 0.1 | 1.4 ± 0.2**** | 0.5 ± 0.0**** | 0.9 ± 0.0**** | 0.1 ± 0.0**** | 0.2 ± 0.0**** | 1.1 ± 0.1**** | 855 | 1036 | 1,2,3 |
| 13.759 | Camphene | 0.3 ± 0.0 | 0.3 ± 0.0 | 0.2 ± 0.0 | 0.2 ± 0.0 | t**** | t**** | 0.2 ± 0.0 | 871 | 1075 | 1,2,3 |
| 15.697 | 1-Octen-3-ol | 0.2 ± 0.0 | 0.1 ± 0.0 | 0.1 ± 0.0 | 0.4 ± 0.0 | t | t | 0.2 ± 0.0 | 896 | 1451 | 1,2 |
| 16.625 | 1-Nonen-3-ol | – | – | t | – | t | 0.1 ± 0.0 | 0.2 ± 0.0 | 908 | 1,2 | |
| 17.144 | β-Pinene | 0.7 ± 0.0 | 0.4 ± 0.0* | 0.3 ± 0.0** | 0.4 ± 0.0**** | 0.1 ± 0.0**** | 0.3 ± 0.0** | 2.1 ± 0.2°°°° | 914 | 1110 | 1,2,3 |
| 17.785 | α-Phellandrene | – | 0.1 ± 0.0 | t | t | t | t | 0.3 ± 0.0 | 923 | 1160 | 1,2,3 |
| 18.684 | δ-2-Carene | 1.1 ± 0.1 | 0.7 ± 0.0** | t**** | 0.6 ± 0.1 | 0.1 ± 0.0**** | 0.5 ± 0.0**** | 2.0 ± 0.1°°°° | 934 | 1146 | 1.2,3 |
| 19.424 | p-Cymene | 17.7 ± 0.2 | 14.1 ± 0.2**** | 10.2 ± 0.1**** | 16.9 ± 0.1**** | 1.6 ± 0.2**** | 6.1 ± 0.3**** | 6.5 ± 0.3**** | 944 | 1179 | 1,2,3 |
| 19.666 | 1,8-Cineole | – | – | – | – | 0.2 ± 0.0 | 0.5 ± 0.0 | 1.1 ± 0.1 | 947 | 1210 | 1,2,3 |
| 19.982 | 1,3,8-p-Menthatriene | – | – | – | – | – | 0.1 ± 0.0 | – | 951 | 1,2 | |
| 20.646 | β-Ocimene | – | – | – | – | t | 0.2 ± 0.0 | 1.0 ± 0.1 | 960 | 1,2,3 | |
| 21.334 | Santolina triene | – | – | – | – | – | 0.1 ± 0.0 | – | 969 | 1043 | 1,2 |
| 21.883 | γ-Terpinene | 5.8 ± 0.1 | 2.8 ± 0.1**** | 1.1 ± 0.2**** | 3.7 ± 0.3**** | 0.8 ± 0.0**** | 2.4 ± 0.09**** | 14.2 ± 0.3°°°° | 976 | 1221 | 1,2,3 |
| 22.442 | Terpinolene | – | 0.4 ± 0.0 | 0.4 ± 0.0 | – | 0.2 ± 0.0 | 0.3 ± 0.0 | – | 983 | 1291 | 1,2,3 |
| 22.725 | cis-Sabinene hydrate | – | 0.2 ± 0.0 | – | – | t | t | 0.3 ± 0.0 | 1009 | 1470 | 1,2 |
| 24.669 | Linalool | 0.1 ± 0.0 | – | 0.3 ± 0.0 | – | 0.6 ± 0.1°°°° | 0.7 ± 0.0°°°° | 1.5 ± 0.2°°°° | 1014 | 1537 | 1,2,3 |
| 25.096 | allo-Ocimene | – | – | – | 0.1 ± 0.0 | 0.1 ± 0.0 | t | 0.5 ± 0.1 | 1041 | 1382 | 1,2 |
| 27.09 | diihydro–Linalool | – | t | t | – | t | t | 0.5 ± 0.0 | 1046 | 1,2 | |
| 29.372 | Isoborneol | 0.4 ± 0.0 | 0.9 ± 0.06°°°° | 0.8 ± 0.1°° | 0.5 ± 0.1 | 0.4 ± 0.1 | 0.5 ± 0.1 | 0.3 ± 0.0 | 1072 | 1642 | 1,2 |
| 30.253 | Terpinen-4-ol | 0.1 ± 0.0 | 0.1 ± 0.0 | 0.2 ± 0.0 | 0.2 ± 0.0 | 0.3 ± 0.0 | 0.4 ± 0.0° | 0.5 ± 0.0°° | 1083 | 1590 | 1,2,3 |
| 31.487 | α-Terpineol | – | t | 0.1 ± 0.0 | – | 0.1 ± 0.0 | 0.1 ± 0.0 | 0.2 ± 0.0 | 1100 | 1662 | 1,2,3 |
| 32.349 | cis-dihydro Carvone | – | – | – | – | 0.1 ± 0.0 | 0.1 ± 0.0 | t | 1106 | 1,2,3 | |
| 34.516 | Thymol, methyl ether | 0.6 ± 0.0 | 0.4 ± 0.0 | 0.5 ± 0.1 | 0.9 ± 0.1° | 1.8 ± 0.3°°°° | 1.2 ± 0.1°°°° | 0.9 ± 0.1° | 1137 | 1597 | 1,2 |
| 35.585 | Tymoquinone | – | t | 3.8 ± 0.2 | 1.1 ± 0.2 | 0.5 ± 0.0 | 3.5 ± 0.2 | 0.5 ± 0.0 | 1152 | 1,2 | |
| 40.059 | Carvacrol | 67.8 ± 0.5 | 73.9 ± 0.6°°°° | 76.1 ± 0.6°°°° | 68.6 ± 0.4°°°° | 81.4 ± 0.6°°°° | 74.5 ± 0.4°°°° | 56.2 ± 0.3**** | 1211 | 2225 | 1,2,3 |
| 44.643 | Carvacryl acetate | – | – | – | – | 0.1 ± 0.0 | 0.3 ± 0.07 | 0.1 ± 0.0 | 1280 | 1868 | 1,2 |
| 46.185 | Caryophyllene | 1.3 ± 0.2 | 1.3 ± 0.2 | 1.5 ± 0.4 | – | 1.3 ± 0.0 | 2.2 ± 0.2 | 2.3 ± 0.1 | 1297 | 1575 | 1,2,3 |
| 46.294 | Isocaryophillene | – | 0.1 ± 0.0 | 0.1 ± 0.0 | 2.4 ± 0.3 | 1.4 ± 0.1 | 0.1 ± 0.0 | 1.2 ± 0.1 | 1299 | 1,2 | |
| 47.157 | α-Humulene | 0.1 ± 0.1 | – | 0.1 ± 0.0 | 0.2 ± 0.0 | 0.5 ± 0.0°° | 0.1 ± 0.0 | t | 1313 | 1671 | 1,2,3 |
| 48.297 | Germacrene A | 0.4 ± 0.2 | 0.1 ± 0.0** | 0.1 ± 0.1** | 0.3 ± 0.0 | 1.8 ± 0.1°°°° | 0.8 ± 0.0* | 1.4 ± 0.2°°°° | 1359 | 1747 | 1,2,3 |
| 50.974 | Caryophyllene oxide | – | – | 0.1 ± 0.0 | – | 0.5 ± 0.1 | 0.3 ± 0.0 | 0.3 ± 0.0 | 1375 | 1989 | 1,2,3 |
| 51.985 | Aromandrene | – | 0.6 ± 0.1 | 0.7 ± 0.0 | 0.2 ± 0.0 | 1.4 ± 0.1 | 1.0 ± 0.1 | 1.7 ± 0.1 | 1391 | 1,2,3 | |
| 52.398 | β–Ylangene | – | – | 0.1 ± 0.0 | – | 0.4 ± 0.0 | 0.4 ± 0.1 | 0.4 ± 0.0 | 1398 | 1589 | 1,2,3 |
| 54.056 | α-Bisabolol | – | – | 0.4 ± 0.0 | – | 1.2 ± 0.1 | 0.2 ± 0.0 | 0.2 ± 0.0 | 1421 | 2232 | 1,2,3 |
| 57.491 | Isodaucene | – | – | – | – | t | t | – | 1479 | 1,2 | |
| 57.74 | Cubebol | – | – | – | – | 0.1 ± 0.0 | – | – | 1483 | 1957 | 1,2,3 |
| 59.449 | δ-Cadinene | – | – | t | – | 0.2 ± 0.0 | t | – | 1506 | 1,2,3 | |
| 60.288 | Germacrene B | – | – | – | – | 0.1 ± 0.0 | – | 0.1 ± 0.0 | 1521 | 1776 | 1,2,3 |
| 62.008 | Cycloisolongifolene, 8-hydro | – | – | – | – | 0.2 ± 0.0 | – | – | 1552 | 1,2 | |
| Total | 98.8 | 97.9 | 98.0 | 98.0 | 97.8 | 97.7 | 97.9 | ||||
| Monoterpenes hydrocarbons | 37.5 | 38.1 | 28.6 | 44.4 | 30.8 | 36.6 | 27.3 | ||||
| Oxygenated monoterpenes | 37.5 | 42.9 | 39.3 | 27.8 | 33.3 | 34.1 | 42.4 | ||||
| Sesquiterpenes hydrocarbons | 25.0 | 19.0 | 25.0 | 27.8 | 25.6 | 24.4 | 24.2 | ||||
| Oxygenated sesquiterpene | 7.1 | 10.3 | 4.9 | 6.1 | |||||||
| Yield (% w/w) | 0.2 ± 0.0 | 0.7 ± 0.0 | 0.4 ± 0.0 | 0.1 ± 0.0 | 0.2 ± 0.0 | 2.2 ± 0.0 | 0.0 ± 0.0 |
Significant values are in bold.
*Significantly different at p value < 0.05, **p value < 0.01; ***p value < 0.001; ****p value < 0.0001 vs. fresh; °significantly different p value < 0.05; °°p value < 0.01; °°°p value < 0.001; °°°°p value < 0.0001 vs. fresh; a,bare the Kovats retention indices determined relative to a series of n-alkanes (C10–C35) on the apolar HP-5 MS and the polar HP Innowax capillary columns, respectively; cidentification method: 1 = comparison of the Kovats retention indices with published data; 2 = comparison of mass spectra with those listed in the NIST 02 and Wiley 275 libraries and with published data; 3 = coinjection with authentic compounds; c -: not detected; t = trace (< 0.1%).