In vitro anti-bacterial activity of methanolic extract of Apium petroselinum L. seed against clinical isolates of Helicobacter pylori

Background and Objective: Helicobacter pylori (HP) is a spiral Gram-negative bacterium that associates with gastritis, peptic ulcer and gastric carcinoma. Since antibiotic resistance of HP is increasing and sometimes the cure achieved with antibiotics is not successful, so introduction of new therapeutic agents for treatment or prophylaxis is important. There are some reports about the effects of parsley seed on gastric problems and in this study its anti-bacterial activity was studied against HP clinical isolates.  Materials and Methods: In this descriptive study, 37 clinical isolates of HP were isolated and identified from biopsy specimens of patients referred to 17 Shahrivar Hospital in Mashhad. Growth inhibition effect of percolated methanolic extract of parsley seed was determined by the filter paper disc diffusion method on Mueller-Hinton agar containing egg yolk emulsion (according to the NCCLS recommendation). Also antibacterial activity of the extract was studied after autoclaving and at pH 5 and 8.  Results: All isolates were susceptible to 2 mg of the extract. The minimum inhibitory concentration (MIC) of methanolic extract was 729 µg/ml by agar dilution. Methanolic extract preserved its anti-Helicobacter pylori activity at 121ºC for 20 min and acidic pH~5.  Conclusion: The results showed that methanolic extract of parsley seed inhibited the growth of HP isolates in vitro. The extract had anti- Helicobacter pylori activity after autoclaving at 121ºC for 20 min and acidic pH~5.