Table 3.
Quenching constants (Ksv), quenching rate constant (Kq), binding constants (Kb), number of binding sites (n) and thermodynamic parameters for interactions between DPP-4 and myricetin, hyperoside, narcissoside, cyanidin 3-O-glucoside, isoliquiritigenin at different temperatures.
| Flavonoid | T (K) | KSV (×104 L mol−1) | Kq (×1012 L mol−1 s−1) | Kb (×104 L mol−1) | n | ΔG (kJ mol−1) | ΔH (kJ mol−1) | ΔS (J mol−1K−1) |
|---|---|---|---|---|---|---|---|---|
| Hyperoside | 298 | 4.83 ± 0.01 | 4.83 ± 0.01 | 7.32 ± 0.014 | 1.04 ± 0.02 | −27.754 | −14.148 | 45.66 |
| 310 | 4.08 ± 0.01 | 4.08 ± 0.01 | 5.87 ± 0.013 | 1.03 ± 0.02 | −28.301 | |||
| Myricetin | 298 | 3.305 ± 0.06 | 3.305 ± 0.06 | 2.76 ± 0.011 | 0.98 ± 0.02 | −25.34 | −36.52 | −37.53 |
| 310 | 2.517 ± 0.05 | 2.517 ± 0.05 | 1.56 ± 0.012 | 0.95 ± 0.02 | −24.88 | |||
| Narcissoside | 298 | 7.212 ± 0.01 | 7.212 ± 0.01 | 81.28 ± 0.013 | 1.22 ± 0.02 | −33.72 | −8.105 | 85.93 |
| 310 | 6.389 ± 0.01 | 6.389 ± 0.01 | 71.61 ± 0.012 | 1.21 ± 0.02 | −34.75 | |||
| Cyanidin 3-O-glucoside | 298 | 3.64 ± 0.04 | 3.64 ± 0.04 | 6.67 ± 0.01 | 1.05 ± 0.01 | −27.52 | −8.246 | 64.68 |
| 310 | 3.08 ± 0.06 | 3.08 ± 0.06 | 5.86 ± 0.013 | 1.04 ± 0.01 | −27.79 | |||
| Isoliquiritigenin | 298 | 2.133 ± 0.04 | 2.133 ± 0.04 | 5.38 ± 0.011 | 1.09 ± 0.01 | −26.99 | −7.952 | 63.88 |
| 310 | 1.37 ± 0.03 | 1.37 ± 0.03 | 4.75 ± 0.012 | 1.12 ± 0.02 | −27.76 |