Table 3.
Concentration of flavonols by HPLC in Monastrell grape berry skin treated with MeJ, BTH and MeJ + BTH.
| Flavonols (µg/g skin) | 2016 | 2017 | ||||||
|---|---|---|---|---|---|---|---|---|
| Control | MeJ | BTH | MeJ + BTH | Control | MeJ | BTH | MeJ + BTH | |
| M-3-glc | 12.8 ± 2.1 a | 16.4 ± 2.6 a | 16.3 ± 3.9 a | 11.6 ± 1.0 a | 10.4 ± 0.8 b | 5.1 ± 1.1 a | 11.1 ± 0.4 b | 6.1 ± 0.9 a |
| Q-3-glc | 26.3 ± 8.0 a | 23.0 ± 1.0 a | 25.1 ± 3.9 a | 20.8 ± 4.5 a | 21.0 ± 2.1 b | 20.2 ± 2.1 b | 23.6 ± 5.1 b | 13.7 ± 1.7 a |
| K-3-gal | 0.5 ± 0.1 a | 0.5 ± 0.2 a | 0.4 ± 0.0 a | 0.4 ± 0.2 a | 1.5 ± 0.1 a | 3.0 ± 0.3 c | 2.7 ± 0.7 bc | 2.0 ± 0.4 ab |
| K-3-glc + S-3-glc | 2.5 ± 1.1 a | 2.4 ± 0.4 a | 2.9 ± 0.3 a | 2.9 ± 0.9 a | 0.1 ± 0.0 a | 0.5 ± 0.4 ab | 0.9 ± 0.1 b | 0.7 ± 0.1 b |
| I-3-glc | 1.0 ± 0.1 a | 1.0 ± 0.5 a | 1.0 ± 0.6 a | 0.9 ± 0.4 a | 9.7 ± 0.7 ab | 12.0 ± 2.5 b | 9.3 ± 0.3 ab | 8.1 ± 1.7 a |
| Q-3glcU | 8.1 ± 2.2 a | 8.3 ± 1.3 a | 8.7 ± 1.4 a | 9.1 ± 1.5 a | 0.1 ± 0.1 a | 0.1 ± 0.0 a | 0.4 ± 0.1 b | 0.3 ± 0.1 b |
| Total flavonols | 51.2 ± 13.1 a | 51.6 ± 2.1 a | 54.4 ± 9.3 a | 45.7 ± 8.0 a | 42.8 ± 2.7 b | 40.8 ± 4.9 b | 47.9 ± 6.1 b | 30.9 ± 3.5 a |
| Myricetin | 12.8 ± 2.1 a | 16.4 ± 2.6 a | 16.3 ± 3.9 a | 11.6 ± 1.0 a | 10.4 ± 0.8 b | 5.1 ± 1.1 a | 11.1 ± 0.4 b | 6.1 ± 0.9 a |
| Quercetin | 34.3 ± 9.8 a | 31.3 ± 1.8 a | 33.8 ± 5.1 a | 29.9 ± 5.9 a | 21.1 ± 2.1 b | 20.3 ± 2.1 b | 24.0 ± 5.0 b | 14.0 ± 1.7 a |
| Kaempferol | 3.0 ± 1.1 a | 2.9 ± 0.3 a | 3.3 ± 0.2 a | 3.3 ± 1.1 a | 1.6 ± 0.2 a | 3.5 ± 0.6 b | 3.5 ± 0.7 b | 2.7 ± 0.4 b |
| Isorhamnetin | 1.0 ± 0.1 a | 1.0 ± 0.5 a | 1.0 ± 0.6 a | 0.9 ± 0.4 a | 9.7 ± 0.7 ab | 12.0 ± 2.5 b | 9.3 ± 0.3 ab | 8.1 ± 1.7 a |
| Syringetin | 0.64 ± 0.27 a | 0.60 ± 0.10 a | 0.72 ± 0.07 a | 0.71 ± 0.22 a | 0.02 ± 0.01 a | 0.13 ± 0.10 ab | 0.21 ± 0.02 b | 0.18 ± 0.03 b |
Abbreviations: M, myricetin; Q, quercetin; K, kaempferol; I, isorhamnetin; glc, O-glucoside; gal, O-galactoside; glcU, O-glucoronide; and S, Syringetin-3-glocoside. Data represent means±SD. Different letters in the same row and for each year indicate significant differences according to the Duncan test (p <0.05).