Inhibitory effect of anti-pyretic and anti-inflammatory herbs on herpes simplex virus replication.

The increasing clinical use of acyclovir, ganciclovir, and foscarnet against herpes simplex virus (HSV), varicella-zoster virus, and cytomegalovirus has been associated with the emergence of drug-resistant herpesvirus strains. To develop anti-HSV compounds from plants, 31 herbs used as antipyretic and anti-inflammatory agents in Chinese medicine were screened. Five different preparations (cold aqueous, hot aqueous, ethanolic, acid ethanolic, and methanolic) from 31 herbs were analyzed by plaque reduction assay, and 7 extracts. which showed significant antiviral activities, were further elucidated for their antiviral mechanisms. Our results showed that ethanolic extract of Rheum officinale and methanolic extract of Paeonia suffruticosa prevented the process of virus attachment and penetration. Aqueous extract of P. suffruticosa and ethanolic extract of Melia toosendan inhibited virus attachment to cell surface. Aqueous extract of Sophora flavescens and methanolic extract of M. toosendan showed no effect on virus attachment and penetration. These data indicated that these 4 herbs have a potential value as a source of new powerful anti-HSV compounds.