Evaluation of antiherpetic activity of crude extract and fractions of Avicenna marina, in vitro

Abstract

Aim: This study was carried out to check antiherpetic substances of crude methanol leaf extract of Avicenna marina and its column chromatographic fractions. Background: Herpes simplex virus 2 (HSV-2) is a harmful pathogen especially in highly susceptible individuals. Materials and methods: The antiherpetic activity of crude methanol extract and sub-fractions was performed in different concentrations (20, 2, 0.2, and 0.02. μg/ml) by use of plaque-forming unit (PFU) assay and real time polymerase chain reaction (PCR) assay. Results: The most active fraction analyzed by NMR contained luteolin 7-O-methylether 3'-O-beta-d-glucoside (LMEG). The other active fraction was detected by HPLC as luteolin. The apparent effective concentrations for 50% plaque reduction (EC50) of crude methanol extract, LMEG, luteolin and ACV were 10, 5, 16.6 and 2.97. μg/ml, respectively. The three extracts showed no cytotoxic effect on Vero cell line at concentrations of 32. μg/ml or below. According to the consequences of time-of-addition studies, antiherpetic compound LMEG exerted an inhibitory effect on the early stage of HSV-2 infection during which it was added. Conclusions: In conclusion, LMEG isolated from A. marina could probably inhibit HSV attachment to the cell membrane and its entry into the cell. © 2013 Elsevier B.V.