Table 2.
Identification of the bound flavonoids of PCR-C by HPLC-Q-TOF-MS/MS.
| No. | RT (Min) |
Molecular Formula |
[M + H]+ (m/z) (Error, ppm) |
Fragment Ions in the Positive Ion Mode |
[M-H]− (m/z) (Error, ppm) |
Fragment Ions in the Negative Ion Mode |
Identification |
|---|---|---|---|---|---|---|---|
| 1 | 8.113 | C27H30O15 | 595.1660 (−0.38) | 449; 287 | 593.1504 (0.55) | 285 | Luteolin 7-O-rutinoside |
| 2 | 9.005 | C22H22O11 | 463.1232 (0.42) | 445; 427; 367; 343; 313; 177 | ND | ND | Flavone-C-glucoside |
| 3 | 9.41 | C27H30O14 | 579.1720 (0.15) | 433; 271 | 577.1553 (−1.03) | 269 | Isorhoifolin |
| 4 | 9.744 | C28H32O15 | 609.1821 (−1.11) | 301; 286; 177; 153; 71 | 607.1655 (1.03) | 301; 242; 299; 284; 164; 151 | Diosmin |
| 5 | 10.046 | C28H32O15 | 609.1820 (−0.11) | 301; 263;153; 85 | 607.1662 (−0.65) | 301; 299; 284; 164 | Neodiosmin |
| 6 | 10.453 | C22H24O10 | 449.1446 (−1.19) | 431; 413; 369; 303; 263; 195 | ND | ND | Chalcone-C-glycoside |
| 7 | 10.455 | C28H34O15 | 611.1979 (0.02) | 465; 449; 431; 303 | 609.1827 (−0.14) | 301 | Hesperidin |
| 8 | 11.252 | C27H32O14 | 581.1872 (−1.14) | 435; 273; 153 | 579.1719 (0.29) | 271; 151 | Narirutin |
| 9 | 12.493 | C28H34O15 | 611.1979 (0.13) | 465; 303; 177 | 609.1827 (−0.16) | 301; 286; 242; 164; 151 | Neohesperidin |
| 10 | 16.049 | C28H34O14 | 595.2025 (−0.38) | 449; 433; 415; 287; 129; 85 | 593.1866 (1.08) | 285; 270; 164; 151 | Didymin |
| 11 | 19.244 | C28H34O14 | 595.2026 (−0.72) | 449; 443; 287; 161 | 593.1870 (0.97) | 327; 309; 285 | Poncirin |
| 12 | 27.484 | C20H20O7 | 373.1284 (0.14) | 358; 343; 315 | ND | ND | Isosinensetin |
| 13 | 28.375 | C20H20O8 | 389.1228 (0.65) | 374; 359; 341; 313 | ND | ND | Monohydroxypentamethoxyflavone |
| 14 | 32.323 | C20H20O7 | 373.1284 (0.34) | 343; 329; 312; 297;151 | ND | ND | Sinensetin |
| 15 | 34.064 | C19H18O6 | 343.1175 (0.18) | 328; 313; 285; 153 | ND | ND | 5,7,8,4′-Tetramethoxyflavone |
| 16 | 37.922 | C21H22O8 | 403.1394 (−1.49) | 388; 373; 355; 327 | ND | ND | Nobiletin |
| 17 | 39.54 | C19H18O6 | 343.1174 (0.56) | 327; 313; 309; 282; 153 | ND | ND | 5,6,7,4′-Tetramethoxyflavone |
| 18 | 41.631 | C22H24O9 | 433.1490 (0.63) | 417; 403; 385; 357 | ND | ND | 3,5,6,7,8,3′,4′-Heptamethoxyflavone |
| 19 | 44.723 | C20H20O7 | 373.1288 (−1.52) | 343; 325; 297 | ND | ND | Tangeretin |
| 20 | 47.401 | C20H20O8 | 389.1238 (−1.25) | 373; 359; 341; 313; 197 | ND | ND | 5-Demethylnobiletin |
[M + H]+, the precursor ion obtained from mass spectrum in positive mode; [M-H]−, the precursor ion obtained from mass spectrum in negative mode. RT: retention time, ND: not detected.