ABSTRACT
Herpes simplex virus type 1 [HSV-1] causes serious infections particularly in immunocompromised patients. Methanolic extract of four plants were evaluated for their anti-viral effects against acyclovir resistant HSV-1 in HeLa cell line. The 50% cytotoxic concentration [CC50] as well as the effective minimal cytotoxic concentration of each plant extract were evaluated by MTT assay. Antiviral effects of the plant extracts on HSV-1 were examined at different concentrations of the extract. The effective minimal cytotoxic concentration was evaluated at different times of virus replication after infection. Virus titration was assessed by tissue culture infectious dose 50 [TCID50] method. Among the 4 plant extracts evaluated only Mentha pulegium L. extract was shown to exert the highest antiviral activity, with selectivity index [SI] 10.25. Direct treatment of HSV-1 with Mentha pulegium L. extract resulted in 1.7 log10 TCID50 reduction in virus titers after one hour. The highest reduction in HSV-1 infectivity was obtained 1 hour after the infection of the cells with virus resulting in 2.1 log10 TCID50 reduction as compared to the control. The antiviral effects of Mentha pulegium L. extract on HSV-1 after virus infection was more remarkable than the virucidal activity
ABSTRACT
Background: 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
Materials and methods: 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
Results: The CC50 value and effective minimal cytotoxic concentration were determined at 780 micro g/ml and 390 micro g/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
Conclusion: 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
ABSTRACT
Profound consumption of medicinal plants products worldwide and public misconception of the products safety puts the urgent need forward as to evaluation of their safe and harmful aspects. In the present study the Lavandula angustifolia essential oil was studied with a view to the foregoing criteria. The antimicrobial, antioxidative, hematologic and cytotoxic properties of Lavandula angustifolia essential oil were studied. The bacterial strains sensitive to Lavandula angustifolia oil were in the following order: S. aureus>E. coli>K. pneumonia>Streptococcus faecalis>P. aeruginosa. Antioxidative property of the oil was carried out using beta carotene bleaching test and the results were compared with the standard synthetic antioxidants. Lipid peroxidation inhibitions were lower than the synthetic antioxidant BHT and BHA. The oil concentration required for 50% [IC50] free radical scavenging of DPPH was 56 micro g/ml with total phenol contents of 85.43 micro g GAE/mg for L. angustifolia oil. Ferricreducing antioxidant power [FRAP] in the blood sera of the rats gavaged with a daily dose of 100 micro l oil increased by 167.57%. Adverse therapeutic effects were noted as a result of feeding the rats with the essential oil. The volatile oil displayed cytotoxic effects on the human tumor cell line [HeLa cells] and peripheral blood cells with the IC50 of 26 and 21 micro g/ml respectively. The mutagenic and antimutagenic properties of various concentrations of Lavandula angustifolia oil on TA98 and TA100 strains Salmonella typhimurium in the presence and absence of S9 fraction were determined. The results show that the Lavandula oil used in the present study may not be consumed without dose determination