Antiviral activity of some South American medicinal plants

Folk medicinal plants are potential sources of useful therapeutic compounds including some with antiviral activities. Extracts prepared from 10 South American medicinal plants (Baccharis trinervis, Baccharis teindalensis, Eup atorium articulatum, Eupatorium glutinosum, Tagetes pusilla, Neurolaena lob ata, Conyza floribunda, Phytolacca bogotensis, Phytolacca rivinoides and He isteria acuminata) were screened for in vitro antiviral activity against he rpes simplex type I (HSV-1), vesicular stomatitis virus (VSV) and polio vir us type 1. The most potent inhibition was observed with an aqueous extract of B. trinervis, which inhibited HSV-1 replication by 100% at 50-200 mu g/m L, without showing cytotoxic effects. Good activities were also found with the ethanol extract of H. acuminata and the aqueous extract of E. articulat um, which exhibited antiviral effects against both DNA and RNA viruses (HSV -1 and VSV, respectively) at 125-250 mu g/mL. The aqueous extracts of T. pu silla (100-250 mu g/mL), B. teindalensis (50-125 mu g/mL) and E. glutinosum (50-125 mu g/mL) also inhibited the replication of VSV, but none of the. e xtracts tested had any effect on poliovirus replication. Copyright (C) 1999 John Whey & Sons, Ltd.