Effects of chlorophyllin on replication of poliovirus and bovine herpesvirus in vitro

Aims: Chlorophyllin (CHLN), a synthetic derivative of chlorophyll, was assayed in the replication of poliovirus (PV-1) and bovine herpesvirus (BoHV-1) in HEp-2 cell cultures. Methods and Results: Virucidal activity of CHLN was evaluated and the time-of-addition assay was performed as follows: before the infection (-1 and -2 h), at the time of the infection (0 h) and after the infection (1 and 2 h). Plaque reduction assay (PRA) showed that CHLN inhibited BoHV-1 and PV-1 infection and the 50% inhibitory concentrations (IC50) against BoHV-1 and PV-1 infection were 8 center dot 6 and 19 center dot 8 mu g ml-1, respectively. The time-of-addition study demonstrated that the CHLN was effective inhibiting viral replication in 51% and 66 center dot 5% for PV-1 and BoHV-1, respectively, at the highest concentration of 20 center dot 0 mu g ml-1, when added during the infection. The directed effect of CHLN on viral strains demonstrated an inhibition of 62% and 66 center dot 4% for PV-1 and BoHV-1, respectively, by PRA. Conclusions: These results demonstrated that CHLN could be used as an antiviral suggesting directed activity on virus particles and on virus-receptor sites to BoHV. For poliovirus, CHLN also demonstrated virucide activity, moreover, showed to inhibit early steps of the replication cycle. Significance and Impact of the Study: CHLN demonstrated promising selectivity index for both virus strains; therefore, it can be used for the development of an antiviral agent.