In vitro assessment of Tribulus terrestri aqueous extract and Benzoxacin fraction against Helicobacter pylori isolates from biopsy samples of Iranian patients

Background& Objectives: Helicobacter pylori (Hp) is related to gastritis, gastric ulcer, duodenal ulcer, and mucosal carcinoma. Emergence of multidrug resistant Hp strains encouraged researchers to find new effective drugs, especially medicinal herbs and plants which usually show fewer side effects. The aim of this study was an in vitro assessment of anti Hp activity of total extract of Tribulus terrestris (T. terrestris Benzoxacin), a local Iranian medicinal plant and its fraction Benzoxacin. Method and Materials: Total aqueous extract of aerial parts of the plant was prepared and liquid extraction with petroleum ether was used to separate its components. LC/MS system proved the existence of Benzoxazine derivative in the water fraction and the thirdʹs fraction. Anti (Hp) effects of total extract and its third fraction were examined by cup plate method and using standard MacFarland. 50 biopsy samples of antrum were detected from patients who were endoscopic candidates in Milad and Fayazbakhsh hospitals of Tehran during 2011. All samples were isolated, diagnosed based on standard methods and biochemical tests and confirmed by PCR method for ureC gene, too. Different dilutions (250, 500,750 and 1000 mg/ml) of total extract were prepared. Clarythromycin (Clr) E-test strips and an identified Hp OC1096 was used, simultaneously. Results: Of 50 biopsy samples, 12 Hp strains were isolated. Rapid urease test were positive in all except one biopsy sample. Existence of ureC gene in all isolates was confirmed except for one strain by PCR. By cup plate method, resistance to concentrations of 1000 and 750mg/ml wase detected in 50% of Hp isolates and 66.6% of them were resistant to concentrations 250 and 500 mg/ml. Also, 83.3% of Hp strains were resistant to Benzoxacin fraction. Clarythromycin sensitivity was detected in 83% of Hp isolates, simultaneously. Conclusion: This study was done as a pilot study for in vitro evaluation of antibacterial effect of total extract of T. terrestris by cup plate method. Existence of high resistant rate (?50%) to different concentrations T. terrestris aqueous extract renders doing test on more Hp strains in future studies highly recommended. In contrast of the similarity of Benzoxazin structure to Ofloxacin, existence of 83.3% resistance among tested isolates showed no anti Hp effectiveness of this fraction.