Table 2.
Content of iridoids, flavonoids and mangiferin in bitter gentian tea decoctions, μg/mL (±SD).
| Compound | G. algida | G. decumbens | G. macrophylla | G. triflora |
|---|---|---|---|---|
| Iridoids | ||||
| Loganic acid | 106.42 ± 1.91 | 32.69 ± 0.59 | 40.09 ± 0.72 | 33.04 ± 0.66 |
| Loganic acid-6′-O-β-d-glucoside | n.d. | 523.10 ± 10.99 | 123.08 ± 2.34 | 592.41 ± 13.03 |
| Swertiamarin | 26.38 ± 0.47 | tr. | 4.02 ± 0.06 | tr. |
| Sweroside | 23.03 ± 0.46 | n.d. | 2.91 ± 0.05 | n.d. |
| Gentiopicroside | 259.57 ± 4.67 | n.d. | 7.08 ± 0.13 | 15.59 ± 0.34 |
| Subtotal | 415.40 | 555.79 | 177.18 | 641.04 |
| Flavonoids | ||||
| Isoorientin | 173.60 ± 2.77 | 14.83 ± 0.27 | 27.83 ± 0.53 | 120.22 ± 1.92 |
| Isoorientin-4′-O-β-d-glucoside | tr. | 40.71 ± 0.89 | 111.10 ± 2.22 | 204.43 ± 3.88 |
| Isovitexin | 37.96 ± 0.75 | 18.11 ± 0.34 | 40.04 ± 0.92 | 9.70 ± 0.19 |
| Saponarin | 25.62 ± 0.46 | 15.50 ± 0.25 | 6.12 ± 0.13 | 29.31 ± 0.59 |
| Isosaponarin | n.d. | tr. | tr. | 21.22 ± 0.45 |
| Isoscoparin | n.d. | tr. | 12.04 ± 0.26 | 20.83 ± 0.48 |
| Subtotal | 237.18 | 89.15 | 197.13 | 405.71 |
| Xanthones | ||||
| Mangiferin | n.d. | n.d. | n.d. | 19.89 ± 0.46 |
| Subtotal | n.d. | n.d. | n.d. | 19.89 |
| Total | 652.58 | 644.94 | 374.31 | 1066.64 |
n.d.—not detected (<limit of detection); tr.—traces amounts (<limit of quantification).