Table 1.
Chemical composition of Trifolium pratense L. essential oil at three different stages of growth.
| Composition (%) | ||||||
|---|---|---|---|---|---|---|
| No | Component | a RI | TP1 | TP2 | TP3 | b Identification |
| 1. | Hexane | 604 | 1.70 | - | - | RI, MS |
| 2. | 2-Pentanonone | 680 | - | 6.66 | - | RI, MS |
| 3. | Methylbenzene | 769 | 2.14 | 2.57 | - | RI, MS |
| 4. | 1,3-Dimethylbenzene | 867 | 1.10 | - | - | RI, MS |
| 5. | 1,4-Dimethylbenzene | 883 | - | 2.01 | - | RI, MS |
| 6. | Pentanoic acid | 904 | - | 2.39 | 1.42 | RI, MS |
| 7. | 7-Octen-4-ol | 963 | 1.47 | 1.35 | 0.88 | MS |
| 8. | Beta-myrcene | 990 | 4.5 | - | - | RT, RI, MS |
| 9. | Cyclopropane | n.d. | 0.36 | - | - | RI, MS |
| 10. | Nonanal | 1108 | - | - | 1.72 | RI, MS |
| 11. | 2,4-Heptadienal | 1011 | - | - | 0.35 | RI, MS |
| 12. | 1-Bromocyclohexane | 1023 | - | - | 1.28 | RI, MS |
| 13. | Fenchyl alcohol | 1140 | 0.40 | - | - | MS |
| 14. | 1,2,6-Hexanetriol | n.d. | - | - | 0.56 | MS |
| 15. | p-Cymene | 1026 | 3.59 | - | - | RT, RI, MS |
| 16. | L-Limonene | 1030 | 3.86 | - | - | RI, MS |
| 17. | Benzaldehyde | 1045 | - | - | 5.52 | RI, MS |
| 18. | Isobornyl thiocyanoacetate | 1790 | 0.76 | - | - | MS |
| 19. | Decane | 1005 | 0.39 | 0.44 | - | RI, MS |
| 20. | Undecane | 1109 | - | 2.94 | - | RI, MS |
| 21. | Dihydrocarvone | 1201 | - | - | 6.47 | RI, MS |
| 22. | Beta-ionone | 1424 | 9.46 | 9.07 | 9.90 | RT, RI, MS |
| 23. | 10-Methylnonadecane | 1943 | 0.61 | - | - | RI, MS |
| 24. | 2(4H)-Benzofuranone, 5,6,7,7a-tetrahydro-4,4,7a-trimethyl | 1527 | 5.60 | 5.77 | 5.81 | MS |
| 25. | 3-hexen-1-ol | 1392 | 2.20 | - | - | MS |
| 26. | Megastigmatrienone | 1560 | - | - | 16.10 | RI, MS |
| 27. | Hexadecane | 1590 | 2.69 | - | - | RI, MS |
| 28. | Dodecanoic acid | 1568 | 0.54 | - | - | RI, MS |
| 29. | 2,6-Diisopropylnaphthalene | 1728 | 7.51 | 5.44 | 1.76 | RI, MS |
| 30. | Tetradecane | 1400 | 0.31 | - | - | RI, MS |
| 31. | Pentadecane | 1498 | - | - | 0.91 | RI, MS |
| 32. | Isopropyl myristate | 1830 | - | 0.51 | - | MS |
| 33. | Tetrahydroionone | 1470 | 1.56 | - | - | RI, MS |
| 34. | Hexahydrofarnesyl acetone | 1922 | 6.29 | 7.63 | - | RI, MS |
| 35. | Ocenol | 2068 | 0.39 | - | - | MS |
| 36. | Phytol | 2128 | - | 14.54 | 15.46 | RI, MS |
| 37. | 4-Bromo-1-methyl-5-nitroimidazole | n.d. | 0.46 | - | - | RI, MS |
| 38. | n-Hexadecanoic acid | 1983 | 3.22 | 2.09 | - | RI, MS |
| 39. | Pentacosane | 2493 | - | 3.81 | - | RI, MS |
| Total identified | 92.00 | 85.61 | 53.69 | |||
| Monoterpenes | 12.00 | - | 6.47 | |||
| Sesquiterpenes | 29.90 | 30.86 | 23.91 | |||
| Diterpenoids | 25.56 | 24.53 | 9.90 | |||
| Aliphatic compounds | 13.34 | 20.20 | 4.85 | |||
| Aromatic compounds | 11.20 | 10.02 | 8.56 | |||
a Retention indices relative to C9–C24 n-alkanes on the HP 5MS column.; (n.d.) not detected; b (MS) mass spectrometry; (RT) comparison of the relative retention time with those obtained from the NIST/NBS, Wiley libraries spectra and literature data.