Effect of active component from radix glycyrrhizae against respiratory syncytial virus

ObjectiveTo study the anti-respiratory syncytial virus(RSV)effect of an component from radix glycyrr hizae(GX)in vitro.MethodsThe cytotoxicity and antiviral of GX were tested by the neutral red assay and cytopathic effect(CPE)inhibition assay,with ribavirin as the positive control drug.ResultsIt showed good inhibitory effect against RSV with the medium cytotoxicity concentration(TC₅₀)460.00 μg/ml,the medium effective concentration(EC₅₀)23.53 μg/ml,and the treatment index(TI)19.55.It also exhibited obvious inhibition on RSV replications when GX was added at 2,4,6,8 and 10h after infection(P<0.01).GXalso displayed direct inactivation on RSV.ConclusionGX can significantly inhibit RSV replications in vitro.