Anti-human immunodeficiency virus type 1 (HIV-1) activity of Achyrocline flaccida Wein DC and Gamochaeta simplicicaulis aqueous extracts

The anti-human immunodeficiency virus type-1 (HIV-1) activity of two South American plant extracts was studied in vitro. The concentrations of aqueous extracts of Achyrocline flaccida Wein DC (AF) and Gamochaeta simplicicaulis (GS) that inhibit 50% of viral production were 3 and 5 μg/mL respectively. The concentrations that inhibit cellular growth were 400 and 600 μg/mL. Non-virucidal activity was detected. The results indicate that the potent anti-HIV-1 activities of both AF and GS extracts might occur at an early step of viral replication on infected lymphocytes of primary origin. © 1997 John Wiley & Sons, Ltd.