Retention time (Rt) (min), maximum absorption in the visible region (λmax) (nm), deprotonated ion ([M-H]) (m/z), mass fragmentation (MS2) (m/z), tentative identification, and quantification (mg/g extract) of the phenolic compounds found (mean ± standard deviation)
| Peak | Rt (min) | λmax (nm) | [M-H] (m/z) | MS2 (m/z) | Tentative identification | Quantification (mg/g extract) | Reference used for identification |
|---|---|---|---|---|---|---|---|
| 1 | 4.35 | 280 | 461 | 315(8), 135(28) | Verbasoside | 4.35 ± 0.27 | [29] |
| 2 | 5.02 | 328 | 487 | 179(100) | Cistanoside F | 3.13 ± 0.09 | [29] |
| 3 | 5.64 | 358 | 389 | 371(23), 345(100), 209(51), 179(10), 121(12) | Theveside | 2.43 ± 0.1 | [29] |
| 7 | 11.51 | 330 | 639 | 621(12), 459(23) | β-hydroxy-verbascoside/β-hydroxy-isoverbascoside | 3.17 ± 0.04 | [29] |
| 8 | 11.97 | 330 | 639 | 621(15), 459(22) | β-hydroxy-verbascoside/β-hydroxy-isoverbascoside | 3.58 ± 0.17 | [29] |
| 9 | 12.69 | 344 | 637 | 351(100), 285(73) | Luteolin 7-O-diglucuronide | 17.02 ± 0.06 | [30] |
| 10 | 14.99 | 314 | 163 | 119(100) | p-Coumaric acid | 2.69 ± 0.05 | [30] |
| 11 | 15.91 | 335 | 621 | 351(100), 269(24) | Apigenin 7-O-diglucuronide | 8.29 ± 0.11 | [30] |
| 12 | 16.66 | 331 | 623 | 461(21), 315(7) | Verbascoside | 115.07 ± 0.21 | [30] |
| 13 | 17.99 | 354 | 651 | 351(100), 299(4) | Chrysoeriol 7-O-diglucuronide | 3.53 ± 0.03 | [30] |
| 14 | 18.69 | 331 | 623 | 461(19), 315(14) | Isoverbascoside | 2.62 ± 0.01 | [30] |
| 15 | 19.23 | 331 | 623 | 461(16), 315(5) | Forsythoside | 8.23 ± 0.36 | [30] |
| 16 | 21.23 | 350 | 491 | 315(100), 300(24) | Isorhamnetin 3-O-glucuronide | 0.76 ± 0.01 | [30] |
| 17 | 22.56 | 332 | 637 | 491(6), 461(63), 315(14) | Eukovoside | 2.06 ± 0.01 | [30] |
| 18 | 22.48 | 332 | 651 | 505(5), 475(27) | Martinoside | 2.36 ± 0.06 | [30] |
| Total caffeoyl phenylethanoid glycoside (mg/g extract) | 147.00 ± 0.15 | ||||||
| Total phenolic acids (mg/g extract) | 2.69 ± 0.05 | ||||||
| Total flavonoids (mg/g extract) | 29.6 ± 0.15 | ||||||
| Total phenolic compounds (mg/g extract) | 179.29 ± 0.35 | ||||||
Rt: retention time; λmax: maximum absorption in the visible region; [M-H]: deprotonated ion; MS2: mass fragmentation
