Table 2.
ENC and Q chemical compositions.
| Tannins Composition | ENC | Q |
|---|---|---|
| Gallic acid | 1–6% | 1–2% |
| Ellagic acid | 1% | − |
| Pentagalloyl glucose | 3% | − |
| Castalin and vescalin | 6.6% | − |
| Castalagin and vescalagin | ~ 30% | − |
| Roburins | 20–24% | − |
| Other major oligomers and glycosides | 20–40% | − |
| Trigalloyl quinic acid | − | − |
| Tetragalloyl quinic acid | − | − |
| Pentagalloyl quinic acid | − | − |
| Esagalloyl quinic acid | − | − |
| Eptagalloyl quinic acid | − | − |
| Fisetinidin and robinetinidin dimers | − | 9–11% |
| Fisetinidin and robinetinidin trimer | − | 38–43% |
| Fisetinidin and robinetinidin tetramer | − | 24–28% |
| Fisetinidin and robinetinidin pentamer | − | 12–15% |
| Fisetinidin and robinetinidin esamers | − | 9–12% |