Inhibitory effect on replication of enterovirus 71 of herb methanol extract

Abstract

Anti-enterovirus 71 (EV 71) activities of fifteen herb plant species extracts were examined by SRB assay, among which Origanum vulgare and Rosmarinus officinalis (Anna Rosemary) extracts exhibited the activities with IC50 of 8.28 and 8.17 μg/mL, respectively. Their 50% cytotoxicity concentrations (CC50) were 691.89 and 1104.19 μg/mL, and the therapeutic indices were 83.56 and 135.15, respectively. Amantadine (positive control) showed anti-EV 71 activity with 50% inhibitory concentration and CC50 of 4.46 and 145.22 μg/mL, respectively. Addition of the methanol extracts of O. vulgare and R. officinalis (Anna Rosemary) in EV 71-infected Vero cells strongly inhibited the formation of visible cytopathic effects without changing the normal morphology of the cells. These results indicate that methanol extracts of O. vulgare and R. officinalis (Anna Rosemary) may contain antiviral compound inhibiting the EV 71 replication.