Bioactivity of Rosemary and Sage Against Measles

Two methanolic extracts of common medicinal plants; Rosmarinus officinalis (rosemary), Salvia triloba (sage), were tested for their antiviral activity against Measles (MV) virus in vitro with the aim of evaluation of the biological activity (cytotoxicity on measles virus) of these aromatic, traditionally used plants in Jordan. A colorimetric tetrazolium-based (MTT) assay as well as visual evaluation of cell morphology using inverted light microscopy has been applied to test cytotoxicity of the different plants concentrations. Antiviral properties of the plant extracts were determined by cytopathic effect inhibition assay using african monkey kidney (Vero) cells. Cytotoxicity results showed that rosemary and sage extracts were toxic at the concentrations 50 and 100 μg /ml to Vero cells. The % inhibition of the Measles virus infectivity was evaluated, Interestingly sage showed a dose dependant inhibition of Measles virus cytopathic effect (CPE) at all virus dilutions A good correlation at the second dilution of the virus was achieved with 50% effective concentration (EC50 =14.74 μg/ml) While rosemary extract exhibited dose-dependent inhibition of Measles virus cytopathic effect at the first dilution of the virus only with an EC50 of 23.96 μg /ml and a considerable inhibition of the viral infectivity with the lowest dilution of virus. Consequently rosemary and sage could be potentially promising for treatment of measles virus and could possess antiviral agents that may act against other viruses too.