INHIBITION OF HSV-1 MULTIPLICATION BY FIVE SPECIES OF MEDICINAL PLANTS

Abstract

Medicinal plants have been traditionally used for different kinds of ailments including infectious diseases. As viral resistance to available chemical drugs causes problems in the treatment of herpes simplex virus type 1 infection, there is an evolving need for new antiherpes drugs. Therefore in the present study 5 species of medicinal plants with ethno-medical background were screened for antiherpes effect against HSV-1in Hep-2(Human epithelial type 2) cells. Different parts of the plants were collected and aqueous extract of them were prepared. These extracts were screened for their cytotoxicity against Hep-2 cell line by cytopathic effect (CPE) assay at concentrations 50-1000 μg/ml. Antiherpes properties of the extracts were determined by cytopathic effect inhibition assay. Four plants extract; Thymus kotschyanus, Echinacea purpurea, Camellia sinensis and Echium amoenum L exhibited significant antiherpes effect against HSV-1 at nontoxic concentrations to the cell lines used. The extracts of Thymus kotschyanus and Camellia sinensis showed highest antiherpes activity against HSV-1 at most concentrations. Our findings indicated that Camellia sinensis extract has inhibit HSV-1 multiplication at concentrations 50-1000 μg/ml while this figure for Thymus kotschyanus is 100-800 μg/ml and for Echinacea purpurea and Echium amoenum L are >400 μg/ml. Four plants extract of assay exhibited significant antiherpes activity at a concentration nontoxic to the cell line used. EC50 of Camellia sinensis extract was best sample and findings showed Camellia sinensis has most selectivity indices. Further research is needed to elucidate the active constituents of these plants which may be useful in the development of new antiviral drugs.