Antiviral Activity in Argentinean Baccharis spp.

VISINTINI JAIME M.F.; RETTA D.; SÜLSEN V; MUSCHIETTI L; MARTINO V; CAMPOS R; CAVALLARO L

Berlín, Alemania

Congreso; 58th International Congress And Annual Meeting Of The Society For Medicinal Plant Research.; 2010

Society for Medicinal Plant and Natural Product Research

Baccharis (B) is a strictly American genus. Several species are considered as medicinal plants (antiseptic, anti-inflammatory, and to treat both gastric ulcers and skin sores). In our search for new antiviral agents, we have examined extracts of five Argentinean Baccharis not previously studied: B. gaudichaudiana DC  (BG), B. penningtonii Heering (BPe), B. phyteumoides (Less.) DC  (BPh), B. spicata (BS) and B. tucumanensis Hook. & Arn. (BT). The aim of this work was to evaluate the antiviral activity of these species against herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) and polio virus type 2 (PV-2) and 3 (PV-3). Dicloromethane:methanol (OE) and aqueous extracts (AE) were tested for cytotoxicity and antiviral activity, by MTS/PMS method (Cytotoxic concentration 50 %) and reduction plaque assays (PFU/ml) in Vero cell cultures and determination of effective concentration 50% (EC50). Results All OE presented antiviral activity against polioviruses and AE against herpesviruses except BPh. To delineate the extract-sensitive phase, Vero cells were infected with HSV-1, with and without AE of BG at 4°C during the absorption step. The results showed significance reduction of viral infectivity.  Similarly, when the OE of BG was evaluated against PV-2 in Vero cells, the major inhibitory effect was exerted in the post-adsorption step. BG was the most active extract against all evaluated viruses. Chromatographic profiles of BG extracts will be presented. Active constituents in both BG extracts and their true mechanisms of action will be studied. To delineate the extract-sensitive phase, Vero cells were infected with HSV-1, with and without AE of BG at 4°C during the absorption step. The results showed significance reduction of viral infectivity.  Similarly, when the OE of BG was evaluated against PV-2 in Vero cells, the major inhibitory effect was exerted in the post-adsorption step. BG was the most active extract against all evaluated viruses. Chromatographic profiles of BG extracts will be presented. Active constituents in both BG extracts and their true mechanisms of action will be studied. BG was the most active extract against all evaluated viruses. Chromatographic profiles of BG extracts will be presented. Active constituents in both BG extracts and their true mechanisms of action will be studied.