- Anti-viral activity of the extracts of a Kenyan medicinal plant Carissa edulis against herpes simplex virus. Tolo, F.M., Rukunga, G.M., Muli, F.W., Njagi, E.N., Njue, W., Kumon, K., Mungai, G.M., Muthaura, C.N., Muli, J.M., Keter, L.K., Oishi, E., Kofi-Tsekpo, M.W. Journal of ethnopharmacology. (2006)