Aims: Gastroenteritis caused by Salmonella typhimurium and the treatment of this disease with antibiotics follows by problems such as drug resistance and side effects emergence. Using herbs and probiotics can be a solution to this problem. The aim of this study was to evaluate the antimicrobial effect of Lactobacillus plantarum with extracts of Satureia hortensis and Anethum geravolens on Salmonella typhimurium in vitro and in animal model.

Methods: In this experimental study, 35 female mice 6 to 8 weeks old were divided into 7 groups of 5. The mice infected with appropriate strains of Salmonella typhimurium. After extraction of Satureia hortensis and Anethum geravolens, antibacterial effect on Salmonella typhimurium was studied in vitro. Antibacterial activity of 5 strains of Lactobacillus plantarum that showed the highest amount of exopolysacharide production studied on Salmonella typhimurium. Mice were treated with oral and growths of Salmonella typhimurium in their feces were assessed. The results were analyzed by one-way ANOVA test in SPSS 18 software.

Results: Mice which treated with ethanolic extract of Satureia hortensis alone and in combination with probiotic showed significant decrease in the rate of excretion and colonization of Salmonella typhimurium in comparison with mice that treated with ethanolic extract of Anethum geravolens alone and in combination with neutralize probiotic and control groups.

Conclusion: Ethanolic extract of Satureia hortensis has a synergistic effect on antimicrobial effect of Lactobacillus plantarum neutralized supernatant against Salmonella typhimurium.