Table 2.
Results of quantification of individual flavonoids, phenolic acids, and xanthines.
| Bioactive compound | Calibration curve | Fraction of flavonoids1 | Fraction of phenolic acids2 | Aqueous solution |
|---|---|---|---|---|
| (mg/g) | (mg/g) | (mg/g) | ||
| Chlorogenic acid | A = 3168.1m + 204.2 (r 2 = 0.9865) | 2.1 | 21.6 | 3.0 |
| Caffeic acid | A = 3313.2m − 475.6 (r 2 = 0.9955) | 1.5 | nd | nd |
| Rutin | A = 6223.4m − 649.8 (r 2 = 0.9833) | 5.2 | 6.8 | 2.3 |
| Quercetin | A = 6902.1m + 723.7 (r 2 = 0.9788) | 2.2 | nd | nd |
| Kaempferol | A = 9349.3m − 732.7 (r 2 = 0.9681) | 4.5 | nd | nd |
| Caffeine | A = 2328.8m + 6439.2 (r 2 = 0.9807) | na | na | 5.4 |
| Theobromine | A = 3405.5m + 1535.9 (r 2 = 0.9667) | na | na | 2.7 |
1Hydrolyzed fraction of flavonoids, 2nonhydrolyzed fraction of phenolic acids used for the spectrophotometric analysis according to the European pharmacopoeia, and nd: not detected, na: not applicable.