Evaluation of antiviral effects of sumac (Rhus coriaria L.) fruit extract on acyclovir resistant Herpes simplex virus type 1

Herpes simplex virus type 1 (HSV-1) is a common virus in human. The rate of drug resistance is increasing in HSV-1. In this study¡ anti-viral effects of Rhus coriaria L. fruit extract was evaluated against acyclovir resistant HSV-1 before¡ during and after the infection of Hela cell line.
In this experimental study¡ the trypan blue and 3-[4¡5-dimethylthiazol-2-yl]-2¡5 diphenyltetrazolium bromide (MTT) tests were used to rule out the potential toxic effects extract on the Hela cell line. Antiviral effects of the extract on acyclovir resistant HSV-1 were evaluated before the infection and at different concentrations of the extract. The effective minimal cytotoxic concentration was assessed at different times of virus replication after virus adsorption. Virus titer was determined by tissue culture infectious dose 50 (TCID50) method.
The CC50 value and effective minimal cytotoxic concentration were determined at 780 µg/ml and 390 µg/ml respectively. Treatment of HSV-1 with extract resulted in 1 log10 TCID50 reduction in virus titers after 3 and 4 hour. The highest reduction in acyclovir resistant HSV-1 infectivity was obtained 2 and 4 hour after the infection of the cells with virus resulting in 1.7 log10 TCID50 reduction as compared with control.
The antiviral effects of Rhus coriaria L. fruit extract on acyclovir resistant HSV-1 after virus infection was more remarkable than the treatment of virus with the extract before virus adsorption. Keywords: Sumac extract¡ Antiviral effects¡ Herpes simplex virus type 1.