Table 3.
Identification and quantification of the phenolic compounds in S. atropurpurea L. stem extracts by HPLC-PDA-ESI/MS.
| Peak No | Rt (min) | λmax (nm) |
[M − H]− m/z |
Identification | Formula | Quantification (µg g−1 Extract (ppm) | Ref | |||
|---|---|---|---|---|---|---|---|---|---|---|
| DCM | Chl | EtOAc | EtOH | |||||||
| 1 | 15.56 | 243, 325 | 353, 191 | Chlorogenic acid | C16H18O9 | 14.81 | 6.08 | 87.99 | 657.78 | [1,2,3] |
| 2 | 16.73 | 240, 321 | 179 | Caffeic acid | C9H8O4 | 2.57 | 5.92 | 130.16 | 45.98 | [4] |
| 3 | 19.42 | 208, 227, 279, 309 | 151 | Vanillin | C8H8O3 | 64.67 | 104.11 | n.d. | n.d. | [5] |
| 4 | 19.86 | 235, 279, 375 | 163 | p-coumaric acid | C9H8O3 | n.d. | n.d. | 16.49 | n.d. | [6,7] |
| 5 | 21.98 | 235, 309 | 163 | p-hydroxycinnamic acid | C9H8O3 | 4.37 | 14.50 | 24.23 | 8.33 | [8] |
| 6 | 22.43 | 212, 270, 336 | 609, 367, 179 | Unknown | - | n.d. | n.d. | n.d. | - | - |
| 7 | 23.52 | 237, 285 | 485, 453, 403 | Unknown | - | n.d. | n.d. | - | n.d. | - |
| 8 | 25.45 | 231, 258, 268, 349 | 285, 447 | Cynaroside | C21H20O11 | 39.79 | 71.22 | 199.97 | 741.60 | [8] |
| 9 | 25.98 | 243,348 | 464 | Isoquercitrin | C21H20O12 | n.d. | n.d. | 108.72 | 205.57 | [8] |
| 10 | 28.59 | 240, 340 | 431 | Hyperoside | C21H20O12 | n.d. | n.d. | 37.58 | 36.13 | [8] |
| 11 | 28.88 | 214, 273, 339 | 579, 455 | Unknown | - | n.d. | n.d. | n.d. | - | |
| 12 | 29.36 | 254, 345 | 463 | Quercimeritrin | C21H20O12 | n.d. | n.d. | 36.05 | 81.36 | [8] |
| 13 | 29.64 | 253, 347 | 447 | Luteolin-hexoside | C21H20O11 | n.d. | n.d. | 467.06 | 564.58 | [8] |
| 14 | 32.57 | 269 | 579 | Syringaresinol hexoside | C28H36O13 | LOQ | LOQ | n.d. | n.d. | [9] |
| 15 | 32.68 | 215, 326 | 515 | Dicaffeoylquinic acid isomer 1 | C25H24O12 | n.d. | n.d. | 46.18 | 224.38 | [4,8] |
| 16 | 34.21 | 214, 335 | 615, 555, 447 | Unknown | - | n.d. | n.d. | n.d. | - | - |
| 17 | 34.65 | 218, 327 | 515 | Dicaffeoylquinic acid isomer 2 | C25H24O12 | n.d. | n.d. | 31.22 | 213.63 | [4,8] |
| 18 | 39.51 | 241, 347 | 285 | Luteolin | C15H10O6 | n.d. | n.d. | 113.66 | 11.14 | [7,8] |
| 19 | 49.15 | 242, 268, 334 | 537, 329, 141 | Unknown | - | n.d. | n.d. | - | n.d. | - |
| Total of phenolic compounds (µg g−1) | 129.15 | 201.83 | 1299.31 | 2790.47 | ||||||
DCM; Dichloromethane extract, Chl; Chloroform extract, EtOAc; Ethyl acetate extract, EtOH; Ethanol extract. The dominant compounds are indicated in bold. n.d.: not detected. LOQ, the limit of quantification. Rt: retention time; [M + H]+: protonated molecule; λmax: ultraviolet absorption maxima.