Fig. 6

Herbal infusions exhibit antiviral activity against SARS-CoV-2 variants of concern. A Vero E6 cells were infected with SARS-CoV-2 wt and the variants of concern Alpha (B.1.1.7) and Beta (B.1.351) after treatment with aqueous infusions of coriander, perilla, or sage at 1 h p.i. for 1 h. SARS-CoV-2 replication was determined by quantification of viral genomes in the supernatant of infected cells at 20 h p.i.. Data are shown in Ct value and calculated relative change in genome copies compared to the untreated control. Each condition was analyzed in duplicate. See Additional file 1 for individual data values. B Caco-2 cells were infected with SARS-CoV-2 wt and two distinct isolates of Delta (B.1.617.2 and AY.6) after treatment with aqueous infusions of perilla or sage at 1.5 h p.i. for 1.5 h. SARS-CoV-2 replication was analyzed at 30 h p.i. by icELISA (α-S staining). Data are expressed as relative change compared to the untreated control. Each condition was analyzed in triplicate. See Additional file 1 for individual data values. The treated conditions were compared to the untreated control by one-way ANOVA. ***, p < 0.001. C Caco-2 cells were infected with SARS-CoV-2 variant of concern Omicron (BA.1) after treatment with aqueous infusions of perilla or sage at 1.5 h p.i. for 1.5 h. SARS-CoV-2 replication was determined by quantification of viral genomes in the supernatant of infected cells at 24 h p.i.. Data are shown in Ct value and calculated relative change in genome copies compared to the untreated control. Each condition was analyzed in triplicate. See Additional file 1 for individual data values. The treated conditions were compared to the untreated control by one-way ANOVA. ***, p < 0.001. **, p < 0.01