Table 1. Total phenolic compounds identified by HPLC analyses of the 4 ethanolic extracts of thermally stressed tomato seedlings, S. lycopersicum.
| No. | Compound | RT in min | Area [mAU*s] | Area (%) | Amount (%) | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Con | CS | HS1 | HS2 | Con | CS | HS1 | HS2 | Con | CS | HS1 | HS2 | Con | CS | HS1 | HS2 | ||
| 1 | Pyrogallol | 2.96 | 2.9 | 2.9 | 2.9 | 11.789 | ND | ND | ND | 0.148 | ND | ND | ND | 0.097 | ND | ND | ND |
| 2 | Quinol | 3.17 | 3.17 | 3.15 | 3.15 | ND* | 519.664 | 93.633 | 77.134 | ND | 11.796 | 1.148 | 1.502 | ND | 7.971 | 1.575 | 1.817 |
| 3 | Gallic acid | 3.65 | 3.74 | 3.65 | 3.66 | ND | 91.146 | 188.64 | 204.735 | ND | 2.069 | 2.312 | 3.988 | ND | 0.434 | 0.966 | 1.466 |
| 4 | Catechol | 5.4 | 5.42 | 5.4 | 5.4 | ND | 149.648 | ND | ND | ND | 3.397 | ND | ND | ND | 2.53 | ND | ND |
| 5 | p-Hydroxy benzoic acid | 7.85 | 7.68 | 7.7 | 7.7 | 138.412 | 251.306 | ND | ND | 1.7382 | 5.704 | ND | ND | 2.087 | 4.095 | ND | ND |
| 6 | Chlorogenic | 9.36 | 9.15 | 9.47 | 9.48 | 5,567.345 | 169.148 | 477.564 | 443.50 | 69.914 | 3.839 | 5.853 | 8.638 | 29.126 | 0.952 | 2.951 | 3.836 |
| 7 | Vanillic acid | 9.73 | 9.63 | 9.63 | 9.65 | 79.33 | 1,445.71 | 3,192.21 | 2,031.868 | 0.996 | 32.85 | 39.12 | 39.576 | 0.673 | 14.658 | 35.621 | 31.692 |
| 8 | Caffeic acid | 10.08 | 9.99 | 10.1 | 10.1 | 91.67 | 200.685 | 40.669 | 25.315 | 1.151 | 4.555 | 0.498 | 0.493 | 0.263 | 0.613 | 0.141 | 0.126 |
| 9 | Syringic acid | 10.53 | 10.36 | 10.51 | 10.53 | 86.423 | 46.697 | 185.65 | 119.32 | 1.085 | 1.06 | 2.275 | 2.324 | 0.359 | 0.211 | 0.905 | 0.817 |
| 10 | p-Coumaric acid | 12.99 | 13.11 | 13.06 | 13.1 | 32.384 | 123.084 | 256.193 | 155.914 | 0.407 | 2.794 | 3.1396 | 3.037 | 0.054 | 0.346 | 0.843 | 0.691 |
| 11 | Benzoic acid | 14.27 | 14.32 | 14.19 | 14.21 | 3.548 | 813.741 | 549.463 | 431.243 | 0.045 | 18.471 | 6.734 | 8.399 | 0.179 | 64.362 | 47.65 | 52.323 |
| 12 | Ferulic acid | 15.46 | 15.47 | 15.33 | 15.52 | 96.773 | 75.768 | 153.086 | 118.24 | 1.215 | 1.72 | 1.876 | 2.303 | 0.367 | 0.309 | 0.685 | 0.741 |
| 13 | Ellagic | 16.9 | 16.9 | 16.90 | 16.99 | ND | ND | ND | 21.548 | ND | ND | ND | 0.42 | ND | ND | ND | 0.189 |
| 14 | o-Coumaric acid | 17.52 | 17.39 | 17.20 | 17.22 | 84.473 | 455.179 | 863.754 | 386.227 | 1.061 | 10.332 | 10.585 | 7.523 | 0.206 | 1.016 | 2.075 | 1.334 |
| 15 | Resvertol | 19.74 | 19.87 | 19.80 | 19.8 | 1,692.71 | 33.148 | ND | ND | 21.257 | 0.752 | ND | ND | 65.998 | 1.272 | ND | ND |
| 16 | Cinnamic acid | 20.56 | 20.17 | 20.39 | 20.42 | 75.056 | 17.605 | 2,158.405 | 1,118.244 | 0.943 | 0.3996 | 26.451 | 21.781 | 1.43E−01 | 3.34E−04 | 6.27E+00 | 4.51E+00 |
| 17 | Rosemarinic acid | 21.93 | 21.87 | 21.99 | 22.04 | 3.268 | 13.029 | 8.11954e−1 | 8.59627e−1 | 0.041 | 0.296 | 0.01 | 0.017 | 0.45 | 1.231 | 0.325 | 0.460 |
Notes:
*
ND: Not detected.
Compounds were identified according to RT of the separated signals. Con, Control; CS, Cold-stressed; HS1, First level of heat stress and HS2, Second level of heat stress.