Antiviral effect of octyl gallate against influenza and other RNA viruses.

Octyl gallate inhibited the multiplication of several RNA viruses with widely different structure and replication strategies; i.e. vesicular stomatitis virus (VSV), influenza virus and poliovirus. In addition, octyl gallate showed virucidal activity against enveloped viruses at high concentrations. Characterization of the mode of action of octyl gallate against influenza virus infection revealed that the reagent delayed the onset of progeny virus formation. It did not, however, affect the rate of the formation, and the addition of the reagent at 2 h postinfection (p.i.), but not at 4 h p.i., almost completely abolished the formation of the progeny viruses, suggesting that the antiviral action of octyl gallate was not the result of a non-specific degeneration of the infected cells, but possibly the result of the inhibition at specific steps in the middle stage of the multiplication of influenza virus.