H.pylori has been discovered as an etiologic agent for peptic ulcer and gastric cancer. It is well known that eradicating H.pylori is an essential step in curing ulcer disease. Many regimens are currently available but none of them can achieve 100% eradication rate .

In this research, anti-bacterial effect of extracts of:fennel, dill, caraway, cinnamon and antibiotics of: ciprofloxacin, Tetracyclin and amoxycillin were investigated against H.pylori by disk diffusion method and flow cytometry. In this study we used culture and rapid urease Test , catalase, oxidase and also staining to recognize H.pylori in 30 biopsies that has been taken from
   patients .

14 cases (46.66%) were positive for H.pylori infection. Disk diffusion method was used to detremine the sensitivity of H.pylori to some selective antibiotics and plant extracts. In analysis of information it has been used from nonparametric Cochran test and for comparisons between plant extracts of different groups, the Mcnemar and Bonferroni tests was used. In this study, bacterial viability was surveyed after being subjected to plant extracts and antibiotics by flow cytometry .

             Results showed that all of the bacteria were susceptible to plant extracts and the highest sensitivity was obtained with dill. All bacteria were susceptible to ciprofloxacin , tetracyclin and were resistant to amoxicillin. Flow cytometry showed that ciprofloxacin had bacteriocidal effect, tetra cyclin had bacteriostatic effect and could not kill bacteria whereas plant extracts had bacteriostatic effect .