Inhibitory effects of various ayurvedic and Panamanian medicinal plants on the infection of herpes simplex virus-1 in vitro and in vivo

Extracts of 40 Ayurvedic medicines and 39 Panamanian medicinal plants were screened for their inhibitory activity on the plaque formation of herpes simplex virus type 1 (HSV-1) in cultured cells. The extracts of 11 plant species showed potent inhibitory activity at a concentration of 100 μg/mL, while those of ten species showed moderate activities. Repeated oral administration of each extract of Rhus acuminata (galls), Saraca indica (bark), Strychnos potatrum (seeds) appreciably suppressed the development of typical skin lesions induced by infection of HSV-1 in BALB/c mice. The extract of S. potatrum prolonged both development of skin lesion and mean survival time. This indicates that S. potatrum is a possible candidate for therapeutic application for HSV-1 infection.