Table 7.
LC–MS identification of the main ions detected during oxidation of sinapic acid by PcLac1 and PcLac2
| Compound | Rt (min) | m/z [M-H]− | MF | MS/MS | Identification | PcLac1 samples | PcLac2 samples |
|---|---|---|---|---|---|---|---|
| Dimers | |||||||
| 17 | 6.19 | 445 | C22H21O10 | 189 (C11H9O3), 174 (C10H6O3), 161 (C9H5O3), 145 (C9H5O2), 121 (C7H5O2) | Disinapic acid | Minor | Major |
| 18 | 6.69 | 445 | C22H21O10 | 189 (C11H9O3), 174 (C10H6O3), 161 (C9H5O3), 145 (C9H5O2), 121 (C7H5O2) | Disinapic acid | Major | Minor |
| 19 | 6.97 | 401.1220 | C21H21O8 |
189 (C11H9O3), 174 (C10H6O3), 161 (C9H5O3), 145 (C9H5O2), 133 (C8H5O2), 121 (C7H5O2) |
Decarboxylated disinapic acid | Not detected | Detected |
| 20 | 7.21 | 401.1220 | C21H21O8 | 189 (C11H9O3), 174 (C10H6O3), 161 (C9H5O3), 145 (C9H5O2), 133 (C8H5O2), 121 (C7H5O2) | Decarboxylated disinapic acid | Not detected | Detected |
| 21 | 6.26 | 357.060 | C18H13O8 | 271 (C14H7O6), 227 (C13H7O4), 199 (C12H7O2), 167 (C12H7O) | Bis-Decarboxylated disinapic acid | Detected | Detected |
| Trimers | |||||||
| 22 | 7.38 | 667.1643 | C33H31O15 | - | Trisinapic acid | Not detected | Minor |
| 23 | 7.09 | 623.1746 | C32H31O13 | 265 (C16H9O4), 209 (C14H9O2), 121 (C7H5O2) | Trisinapic acid, decarboxylated | Not detected | Detected |
| 24 | 7.55 | 623.1746 | C32H31O13 | 265 (C16H9O4), 209 (C14H9O2), 121 (C7H5O2) | Trisinapic acid, decarboxylated | Not detected | Detected |
| 25 | 8.16 | 579.1846 | C31H31O11 | 339 (C19H15O6) | Trisinapic acid, bis-decarboxylated | Not detected | Detected |
| Tetramers | |||||||
| 26 | 6.98 | 891.2319 | C44H43O20 | 341 (C19H17O6), 189 (C11H9O3), 174 (C10H6O3), 161 (C9H5O3), 145 (C9H5O2), 121 (C7H5O2) | Tetrasinapic acid | Not detected | Detected |
| Others | |||||||
| 27 | 7.99 | 503.1172 | C24H23O12 | 147 (C8H3O3) 119 (C7H3O2) | Unknown compound | Detected | Not detected |