Table 2.
EC50 values were calculated by modeled dose–response curves against the wild-type SARS-CoV-2 pseudovirion model using non-linear regression.
| Extract number | Plant name | Plant part | Extraction method | EC50 % Inhibition (µg/mL) ± SEM |
EC50 % Cytotoxicity (µg/mL) ± SEM |
EC50 % Cell viability (µg/mL) ± SEM |
Selectivity index | |||
|---|---|---|---|---|---|---|---|---|---|---|
| HEK-293-ACE2 | HEK-293-ACE2 | HaCaT | HEK-293-ACE2 | HaCaT | HEK-293-ACE2 | HaCaT | ||||
| 1428 | Solidago altissima L. | Flowers |
dH2O 20 min decoction |
2.60 ± 0.23 | > 1000 | > 1000 | 191.48 ± 13.57 | > 1000 | 73.58 | > 384.61 |
| 1749 | Salix nigra Marshall | Bark |
80% EtOH (aq) 2 × 72 h maceration |
7.98 ± 1.32 | > 1000 | > 1000 | 114.08 ± 6.75 | 241.79 ± 62.50 | 14.30 | 30.32 |
| 1804 | Pteridium aquilinum (L.) Kuhn | Rhizomes |
80% EtOH (aq) 2 × 72 h maceration |
7.43 ± 1.50 | > 1000 | > 1000 | 134.04 ± 8.93 | 145.19 ± 28.93 | 18.04 | 19.54 |
| DMSO | – | – | – | > 1000 | > 1000 | > 1000 | > 1000 | > 1000 | – | – |
| Water | – | – | – | > 1000 | > 1000 | > 1000 | > 1000 | > 1000 | – | – |
| HCQ | – | – | – | 1.14 ± 0.19 | > 1000 | 136.54 ± 74.38 | 109.90 ± 3.73 | 125.99 ± 7.44 | 96.00 | 110.52 |
These experiments were performed in duplicate with 3 technical replicates for an n of 6.
SEM standard error mean, HCQ hydroxychloroquine.
Selectivity index calculation: (EC50% Cell viability (µg/mL)) divided by (EC50% Inhibition (µg/mL)). Accompanying plots can be found in Supplementary Material 6.