Antibacterial Activity of Garlic (Allium sativum L.) on Multi-Drug Resistant Helicobacter pylori Isolated From Gastric Biopsies

Background: garlic (allium sativum l.) exhibit a broad-spectrum of antimicrobial activity against both gram negative and gram-positive bacteria. helicobacter pylori (h. pylori) is the main factor in peptic and duodenal ulcer diseases. some strains of h. pylori have become resistant to the current antibiotics. objectives: the purpose of this study was to determine the antibacterial effects of garlic on h. pylori. materials and methods: the gastric biopsies were inoculated on brucella agar base (conda pronadisa, spain) supplemented with 5% sterile sheep blood, 7 % fetal calf serum, vancomycin (5 mg/l), trimethoprim (5 mg/l), and polymyxin b (2500 u/l). antibiotic susceptibility to garlic and commercial antibiotic disc was determined by agar disc diffusion method. results: in this study, ten strains of h. pylori out of 120 samples were isolated. the minimum inhibitory concentration of garlic extract for all isolates ranged between 25- 400 mg/ml. resistance rates of 10 strains of h. pylori to amoxicillin, ciprofloxacin, clarithromycin, metronidazole, and tetracycline were 20%, 20%, 30%, 60%, and 30%, respectively. conclusions: in this study, the antibacterial effect of aqueous extract of garlic on all h. pylori clinical isolates was confirmed. these findings might help us to use a new strategy for treatment of peptic ulcer.