Table 1.

Studies reporting antiviral activity of natural flavonoids against human and non-human coronaviruses.

Coronavirus	Compounds	Effects	Methods	Reference
Porcine epidemic diarrhea virus (PEDV)	Quercetin 7-rhamnoside	IC50 = 0.014 μg/ml	Vero cells	[43]
Bovine coronavirus (BCV)	Theaflavins	EC50 = 34.7 μg/ml	HRT-18 cells	[42]
HIV/SARS pseudotyped virus	Quercetin	EC50 = 83.4 μM	Vero E6 cells	[45]
HIV/SARS pseudotyped virus	Cinnamomi Cortex extract	IC50 = 37.3 μg/ml	Hep-G2 cells	[46]
SARS-CoV	Baicalin	EC50 = 12.5-25 μg/ml	fRhK4 cell line	[44]
SARS-CoV	Luteolin	EC50 = 10.6 μM	Vero E6 cells	[45]
SARS-CoV	Cinnamomi Cortex extract	IC50 = 7.8 μg/ml	Vero E6 cells	[46]
SARS-CoV	Procyanidin A2 Procyanidin B1 Cinnamtannin B1	IC50 = 30-40 μM	Vero E6 cells	[46]