Table 1.
Method parameters
| Authentic compound | Retention timea (min) | Scan mode | Precursor ion | Product ion I | Product ion II | Cone voltage (V) | Collision energy (eV) | LODb (fmol) | Linear range (pmol) | R2 |
|---|---|---|---|---|---|---|---|---|---|---|
| Strigol | 3.50 ± 0.02 | + | 347 | 96.9 | 233 | 18 | 15 | 2.5 | 0.0125–2.5 | 0.995 |
| Solanacol | 3.54 ± 0.01 | + | 343 | 96.9 | 183 | 15 | 20 | 0.25 | 0.00125–2.5 | 0.997 |
| Orobanchol | 4.59 ± 0.01 | + | 347 | 97 | 205 | 15 | 20 | 1.25 | 0.0025–2.5 | 0.998 |
| Sorgomol | 4.85 ± 0.02 | + | 347 | 233 | 133 | 15 | 25 | 2.5 | 0.0125–2.5 | 0.992 |
| Sorgolactone | 7.48 ± 0.01 | + | 317.1 | 96.9 | 133 | 20 | 23 | 0.125 | 0.00025–2.5 | 0.998 |
| 4-DO | 7.94 ± 0.01 | + | 331.1 | 96.9 | 216 | 15 | 18 | 0.125 | 0.00025–2.5 | 0.999 |
| 5-DS | 8.00 ± 0.01 | + | 331.1 | 96.9 | 216 | 15 | 18 | 0.125 | 0.00025–2.5 | 0.999 |
| Carlactonoic acid | 8.28 ± 0.01 | – | 331 | 113 | 242 | 20 | 12 | 2.5 | 0.005–2.5 | 0.997 |
| Carlactone | 9.63 ± 0.02 | + | 303 | 96.9 | 285 | 15 | 18 | 2.5 | 0.0125–2.5 | 0.992 |
| Internal standard | Quantified analyte | |||||||
|---|---|---|---|---|---|---|---|---|
| GR24 | 5.13 ± 0.01 | + | 299 | 96.9 | 185 | 20 | 20 | Strigol, solanacol, orobanchol, sorgomol |
| [2H6]-2′-epi-5-DS | 7.88 ± 0.01 | + | 337 | 96.9 | 221 | 15 | 18 | 4-DO |
| [2H6]-5-DS | 7.94 ± 0.01 | + | 337 | 96.9 | 221 | 15 | 18 | Sorgolactone, 5-DS |
aValues are mean ± SD (n = 5); b The signal-to-noise ratio was set to 3:1
MRM transitions of authentic SLs and corresponding internal standards, including optimized instrument settings and UHPLC–MS/MS method parameters (retention time, limit of detection—LOD, linear range and coefficient of determination—r2)