INHIBITORY ACTIVITY OF EXTRACTS OF ALTERNANTHERA-BRASILIANA (AMARANTHACEAE) AGAINST THE HERPES-SIMPLEX VIRUS

Five extracts from A. brasiliana, obtained through different procedure s, showed anti-HSV activity. The best activity was detected in a fract ion (B) that was obtained from the crude cold aqueous extract on Sepha dex G(15). Fraction B showed low cellular toxicity and inhibition from 32.4% to 99.9% at concentrations from 6.2 to 50.0 mu g/mL, exhibiting a therapeutic index of 32. Fractions obtained on Sephadex G(100) and reversed-phase column also showed considerable inhibition. Fraction B did not show any virucidal activity, however, its inhibitory activity was revealed during the later stages of the virus replication cycle. T his fraction showed activity on DNA synthesis of infected cells.