Melissa officinalis Extract Inhibits Herpes Simplex Virus-I Glycoprotein B Interaction with Heparin Sulfate

Herpes simplex virus 1, HSV1, is the primary cause of herpes labialis in humans. Drugslikeacycloviranditsderivativesareavailablefortreatment,butwithincreased use and the number of immune compromised patients, the development of resistance to these drugsisincreasing. Extracts of the botanical, Melissa officinalis, have previously been reported to contain antiviral activity toward HSV1. Our initial studies confirmed earlier results that constituents of Melissa officinalis interacted directly with the virus and inhibited HSV1 binding to cells during the initiation of infection. Further studies demonstrated that a component in Melissa officinalis bound specifically to the viral glycoprotein B. Virion structure was shown to be stable at low concentrations of Melissa officinalis, however at a ten-fold higher concentration than that which inhibited binding, virion structure was completely disrupted suggesting a second, virucidal, mode of inhibition. Melissa officinalis was shown to inhibit other alpha herpes viruses as well as having intermediate inhibitory activity against other viruses from the adenoviridae, poxviridae, papovaviridae, and rhabdoviridae families.