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Introduction: Nowadays, the attention of researchers has been focused on natural medicine in order to avoid the detrimental side effects of chemical drugs. In this study we assessed the effect of root extract of Tagetes minuta against HSV-1 and HSV-2. Materials and Methods: This research is an experimental study. Root extract of Tagetes minuta was obtained with 70% ethanol by maceration. Vero cells were grown in DMEM containing 5% fetal bovine serum. Serial dilutions of extracted suspension (1/10, 1/20, 1/40, 1/80, 1/160) were incubated by the exact titer of viruses and monitored for antiviral activity of extract. Data was analyzed using Doncan test. Results: Root extract obtained from Tagetes minuta significantly has antiviral activity against HSV-1 and HSV-2. This extract has more effect on HSV-2 than HSV-1. This study indicates that antiviral activity of the extract varies between different concentrations and the optimum antiviral activity on both viruses was obtained using 1/10 concentration. Conclusion:The results of this investigation showed that root extract of Tagetes minuta have good antiviral potenoial against HSV-1 and HSV-2, a good source of drug for treatment of diseases due to HSV-1 and HSV-2.

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Introduction: Extracts of leaves from Camellia sinensis L contains polyphenolic components with antimicrobial activity. In this investigation biofilm inhibitory effects of black and green tea extracts were defined for five members of enterobacteriacea family including: Enteropathogenic Escherichia coli, Shigella flexneri, Proteus mirabilis, Klebsiella pneumoniae and Salmonella enterica serovar Typhimurium. Because tea is the most widely drunk beverage in Iran, therefore investigation of its effects on enterobacterial biofilm formation and colonization is very important. Materials and Methods: In this experimental study after extraction of samples with Soxhlet extractor in water/ methanol solution, further extraction took place in Ethyl acetate phase. The extracts preserved in 4oC refrigerator after sterilization by 0.44 µ filters. Well diffusion (Kirby Bauer) and broth dilution methods were used for evaluation of minimum inhibitory concentration of biofilm formation in black and green tea extracts treated cultures. Evaluation of biofilm formation was assayed by observation of colony forming unit of cultured bacteria per milliliter by sampling from Erlenmeyer flask wall scratching onto Tripticase soy agar medium and comparing the results with controls. Analysis of data was done using analysis of variance. Results: Biofilm inhibitory effects of black tea were greater than green tea. The concentration of 4.5 mg/ml of black tea and 5mg/ml of green tea had bactericidal effects against examined bacteria. On Mueller Hinton agar, Proteus mirabilis was more sensitive to black tea EPEC was more sensitive to green tea and Klebsiella pneumoniae showed more resistance to both extracts. Conclusion: Due to the fact that gastrointestinal tract is directly affected with consumed beverage, the high concentration of tea entered in lumen can reduce the number of enterobacteriaceae and can reduce their carcinogenic amine products. Thus it plays an important role in inhibition of gastrointestinal lymphoma and colon carcinoma. Also application of tea polyphenols as a food preservative can be useful.