Table 1. Isoflavone metabolites identified in the plasma following Cheonggukjang ingestion.
| No | Metabolites | Exact mass (m/z) | Actual mass (m/z) | Mass error (mDa) | RT (min) | MS fragments | |
|---|---|---|---|---|---|---|---|
| 1 | Intact isoflavones | Daidzein | 253.0501 | 253.0499 | -2.20 | 7.44 | 195 |
| 2 | Genistein | 269.045 | 269.0455 | 0.5 | 8.80 | 224, 201, 183 | |
| 3 | Glycitein | 283.0606 | 283.0613 | 0.7 | 6.46 | 269, 266, 240 | |
| 4 | Phase I metabolites | 3-hydroxydaidzein | 269.045 | 269.0473 | 2.3 | 5.26 | 253 |
| 5 | 2-hydroxygenistein | 285.0399 | 285.0425 | -1.55 | 8.17 | 269 | |
| 6 | Phase II metabolites | Daidzein 4′-glucuronide | 429.0822 | 429.0894 | 7.2 | 3.85 | 253 |
| 7 | Daidzein 7-glucuronide | 429.0822 | 429.0826 | 0.4 | 5.02 | 253 | |
| 8 | Daidzein diglucuronide | 605.1143 | 605.1157 | 1.4 | 2.85 | 429, 253 | |
| 9 | Daidzein 4′-sulfate | 333.0069 | 333.0071 | 0.2 | 6.34 | 253 | |
| 10 | Daidzein 7-sulfate 4′-glucuronide | 509.039 | 509.0398 | 0.8 | 4.55 | 253 | |
| 11 | Genistein-7-glucuronide | 445.0771 | 445.0790 | 1.9 | 5.92 | 300, 269, 206,134 | |
| 12 | Genistein diglucuronide | 621.1092 | 621.1094 | 0.24 | 2.93 | 445, 269 | |
| 13 | Genistein 7-glucuronide 4′-sulfate | 525.0339 | 525.0346 | 0.7 | 4.53 | 349, 269, 224, 133 | |
| 14 | Genistein 4′-sulfate | 349.0018 | 349.0023 | 0.48 | 6.6 | 269, 224, 133 | |
| 15 | Genistein 7-sulfate | 349.0018 | 349.0019 | 0.1 | 7.48 | 349, 269 | |
| 16 | Gut-mediated metabolites | Dihydrogenistein | 271.0606 | 271.0600 | -0.6 | 8.82 | 165 |
| 17 | Dihydrodaidzein sulfate | 335.0225 | 335.0237 | 1.2 | 6.50 | 253 | |
| 18 | Equol-7-glucuronide | 417.1186 | 417.1180 | -0.6 | 5.52 | 241, 175, 113 | |
| 19 | Equol-4′-sulfate | 321.0433 | 321.0420 | -1.31 | 7.24 | 241, 135, 119 | |
| 20 | 5-hydroxy equol | 257.0814 | 257.0459 | 2.6 | 7.44 | 257, 151, 105 | |
| 21 | O-Desmethylangolensin | 257.0814 | 257.0866 | 5.2 | 9.64 | 257 | |
MS, mass spectrometry; RT, retention time; m/z, mass/charge.