Abstract

In order to find new and effective antiviral agents from natural sources, the antiviral properties of methanol and aqueous extracts of Ballota glandulosissima Hub.-Mor. & Patzak were evaluated by Colorimetric XTT test against Respiratory syncytial virus (RSV). The concentration required to provide 50% protection against cytopathic effects caused by the virus was defined as EC50, the selectivity index (SI) was determined from the ratio of CC50 (50 % Cytotoxic concentration) to EC50. The results showed that both the methanol (EC50 = 12.45 µg/mL; SI = 24.84) and aqueous extracts (EC50 = 19.12 µg/mL; SI = 24.59) of B. glandulosissima had almost the same strong anti-RSV activity as well as ribavirin, used as a positive control against RSV (EC50 = 3.25 µg/mL, SI = 34.89). In conclusion, we can say that B. glandulosissima extracts are worthy of further studies in order to develop an alternative to the drugs used in clinical practice against RSV. This is the first report on the antiRSV activity of B. glandulosissima.