Table 1.
Inhibitory activities on PTP1B and α-glucosidase of isolated compounds.
| PTP1B |
α-Glucosidase |
|||||
|---|---|---|---|---|---|---|
| Compounds | IC50 (μM)a | Ki (μM)b | Type of inhibition | IC50 (μM)a | Ki (μM)b | Type of inhibition |
| 1 | 1.9 ± 0.1 | 0.8 ± 0.1 | Mixed Type I | 30.7 ± 1.5 | 26.7 ± 1.4 | Noncompetitive |
| 2 | 3.9 ± 0.3 | 3.2 ± 0.2 | Mixed Type I | 18.4 ± 0.9 | 17.2 ± 1.0 | Noncompetitive |
| 3 | 7.8 ± 0.6 | 8.1 ± 0.6 | Mixed Type I | 19.6 ± 1.1 | 18.1 ± 0.9 | Noncompetitive |
| 4 | 5.9 ± 0.4 | 6.1 ± 0.5 | Mixed Type I | 6.5 ± 0.5 | 7.1 ± 0.6 | Noncompetitive |
| 5 | 3.8 ± 0.3 | 3.5 ± 0.3 | Mixed Type I | 78.9 ± 2.1 | 72.6 ± 2.3 | Noncompetitive |
| 6 | 4.9 ± 0.5 | 3.8 ± 0.3 | Mixed Type I | 17.8 ± 1.1 | 16.9 ± 1.2 | Noncompetitive |
| 7 | 8.2 ± 0.6 | 7.9 ± 0.4 | Mixed Type I | 25.8 ± 1.2 | 24.4 ± 1.3 | Noncompetitive |
| 8 | 6.6 ± 0.5 | 6.2 ± 0.4 | Mixed Type I | 2.2 ± 0.2 | 3.6 ± 0.3 | Noncompetitive |
| NaVO4d | 32.6 ± 1.5 | NTc | NTc | >200 | NTc | NTc |
| Voglibosed | >200 | NTc | NTc | 24.5 ± 1.2 | NTc | NTc |
a
All compounds were examined in as set of experiments repeated three times; IC50 values of compounds represent the concentration that caused 50% enzyme activity loss.
b
Values of inhibition constant.
c
NT: not tested.
d
Positive control.