In vitro assessment of the antiviral potential of trans-cinnamic acid, quercetin and morin against equid herpesvirus 1

The antiviral activity of quercetin, morin and trans-cinnamic acid was evaluated in vitro against equid herpesvirus 1 (EHV-1) by determining the virucidal activity and using the time of addition assay to test inhibition of the viral replication cycle. The cytotoxicity of each substance was assessed using MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide]. Quercetin showed virucidal action and inhibition of the viral replication cycle at 0 and 1 h. Morin showed potential virucidal and viral replication cycle inhibition at 0 h. Trans-cinnamic acid did not show virucidal activity but inhibited the viral replication cycle at −1 and 0 h. This study demonstrates the potential of these compounds as future antiviral candidates in relation to viruses of importance in veterinary medicine.