Similar to the last blog, a group of Ladake Akintola Unyv. of Technology, Ogbomoso, Oyo State Nigeria has evaluated the inhibitory effects of saponins and tannins by molecular docking and molecular dynamics simulations, targeting SARS-CoV-2 precursor protein main protease (Mpro).
https://link.springer.com/article/10.1007/s40203-020-00071-w
Saponins are found in plant roots, leaves, stems, etc., but are especially found in beans and are known to have antioxidant properties. On the other hand, tannins are astringent components contained in many seeds, and astringency of persimmons is a good example of tannin. Tannins strongly bind to proteins and have the effect of causing denaturation, and the effect of tannins on their properties is called “Astringent.”
The results are as follows, but may show potential antiviral effects that are no less so than remdesivir. Evaluation in vivo is expected.
| Ligands | Binding affinity (ΔG) kcal/mol | Inhibition constant (Ki), µM |
| Saponins | ||
| Priverogenin A | − 8.3 | 0.83 |
| Arjunic acid | − 8.1 | 1.16 |
| Theasapogenol B | − 8.1 | 1.16 |
| Euscaphic Acid | − 8.0 | 1.37 |
| Tannins | ||
| Punicalagin | − 9.0 | 0.25 |
| Punicalin | − 8.6 | 0.5 |
| Ellagic acid | − 8.4 | 0.7 |
| Corilagin | − 8.2 | 0.98 |
| Gallagic acid | − 8.1 | 1.16 |
| Reference | ||
| Remdesivir | − 7.6 | 2.7 |