. 2021 Jul 16;11:14571. doi: 10.1038/s41598-021-93361-y

Table 1.

Efficacy of extracts and compounds in vitro.

	EC50 (μg/ml)^a		CC₅₀ (μg/ml)^b	SI^c
	Pretreatment assay	Treatment assay	CC₅₀ (μg/ml)^b	SI^c
VeroE6 cells
Extract
A. annua ethanolic extract	173	142	1044	6/7
A. annua aqueous extract	390	260	2721	7/10
Compound
Artemisinin	238	151	8216	35/54
Artesunate	12	7	41	3/6
Artemether	147	98	360	2/4
Huh7.5 cells
Extract
A. annua ethanolic extract	118		483	4
Compound
Artemisinin	> 208		5066	< 24
Artesunate	11		93	8
Artemether	64		127	2
A549-hACE2 cells
Extract
A. annua ethanolic extract	83		506	6
Compound
Artemisinin	168		1527	9
Artesunate	12		27	2
Artemether	53		380	7

^aEC₅₀, median effective concentration (µg/mL) was determined in VeroE6 cells in pretreatment or treatment antiviral assays or in Huh7.5 cells and A549-hACE2 cells in treatment antiviral assays as described in Material and Methods. For artemisinin in Huh7.5 cells, < 50% inhibition was observed at the highest non-cytotoxic concentration where cell viability was > 90% of that of non-treated control cultures.

^bCC₅₀, median cytotoxic concentration (µg/mL) was determined as described in Material and Methods.

^cSI, selectivity index, was determined as CC₅₀ divided by EC₅₀ based on results in pretreatment/treatment antiviral assays in VeroE6 cells or based on results in treatment antiviral assays in Huh 7.5 cells and A549-hACE2 cells.