Table 1.
Characteristics of secondary compounds identified by HPLC-DAD-ESI-MS in nectarine fruit surface waxes
| Peak | Proposed structure | Abbreviation | RT | λ max | MS (m/z) | MS2 (m/z) | MS3 (m/z) |
|---|---|---|---|---|---|---|---|
| 1 | p-coumaroylpentacetyldihexoside | cpdh1 | 18.5 | 311 | 697 | 655, 637, 613, 595, 391 | [637]: 595, 577, 553, 535, 331, 287 |
| 2 | p-coumaroylpentacetyldihexoside | cpdh2 | 19.0 | 315 | 697 | 655, 637, 613, 595, 391 | [637]: 595, 577, 553, 535, 331, 287 |
| 3 | trihydroxy-urs-12-en-28-oic acida | thu1 | 45.5 | 198 | 487 | 409 | [409]: 391, 379 |
| 4 | trihydroxy-urs-12-en-28-oic acida | thu2 | 47.0 | 198 | 487 | 469 | [469]: 451, 439, 423, 387 |
| 5 | 2α,3β-dihydroxyolean-12-en-28-oic acid (maslinic acid) (S) | Mas | 49.5 | 198 | 471 | 425, 407 | [407]: 389, 377, 351, 279, 253, 205 |
| 6 | 2α,3β-dihydroxyurs-12-en-28-oic acid (corosolic acid) (S) | Cor | 50.5 | 198 | 471 | 407 | [407]: 389, 377, 351, 279, 253, 205 |
| 7 | p-coumaroyl-2,3-dihydroxy-urs-12-en-28-oic acida | cdhu1 | 51.5 | 198/311 | 617 | 573, 497 | [573]: 529 |
| 8 | p-coumaroyl-2,3-dihydroxy-urs-12-en-28-oic acida | cdhu2 | 51.7 | 198/308 | 617 | 573, 497 | [573]: 529 |
| 9 | p-coumaroyl-2,3-dihydroxy-urs-12-en-28-oic acida | cdhu3 | 52.0 | 198/312 | 617 | 573, 497 | [497]: 453, 407, 391 |
| 10 | p-coumaroyl-2,3-dihydroxy-urs-12-en-28-oic acida | cdhu4 | 52.3 | 198/308 | 617 | 573, 497 | [573]: 529 |
| 11 | p-coumaroyl-2,3-dihydroxy-urs-12-en-28-oic acida | cdhu5 | 53.0 | 198/310 | 617 | 573, 497 | [573]: 529 |
| 12 | p-coumaroyl-2,3-dihydroxy-urs-12-en-28-oic acida | cdhu6 | 54.0 | 198/308 | 617 | 573, 497 | [497]: 453, 407, 391 |
| 13 | feruloyl-2,3-dihydroxy-urs-12-en-28-oic acida | fdhu | 54.5 | 198/322 | 647 | 632-617-603-588-497-453-193 | [497]: 453, 407, 391 |
| 14 | 3β-hydroxy-olean-12-en-28-oic acid (oleanolic acid) (S) | Ole | 56.5 | 198 | 455 | 407 | [407]: 439, 421, 407, 391, 377 |
| 15 | 3β-hydroxy-urs-12-en-28-oic acid (ursolic acid) (S) | Urs | 57.0 | 198 | 455 | 407 | [407]: 439, 421, 407, 391, 377 |
| 16 | 3β-p-coumaroyloxy-urs-12-en-28-oic acida | cou1 | 63.8 | 198/311 | 601 | 555, 437 | [555]: 525, 367, 351 |
| 17 | 3β-p-coumaroyloxy-urs-12-en-28-oic acida | cou2 | 64.0 | 198/308 | 601 | 555, 437 | [437]: 423 (tr) |
| 18 | 3β-p-coumaroyloxy-urs-12-en-28-oic acida | cou3 | 65.0 | 198/309 | 601 | 555, 437 | [437]: 391 (tr) [555]: 539, 525, 351 |
| 19 | 3β-p-coumaroyloxy-urs-12-en-28-oic acida | cou4 | 65.2 | 198/312 | 601 | 555, 437 | [437]: 391, 367 |
a Ursolic acid or oleanolic acid as principal structure.
Peaks are numbered as in Fig. 2; quantified compounds are in bold. (S), Structure confirmed by standard; RT, retention time in min; λ max, wavelength of absorption maxima. MS gives the parent ion for [M-H]– (m/z), MS2 and MS3 the fragmentations of the parent ion and the given selected ion, respectively. The major fragment ion is in bold. tr, Traces.