In vitro anti-bacterial activity of cumin (Cuminum cyminum L.) and tarragon (Artemisia dracunculus L.) extracts against clinical isolates of Helicobacter pylori
Helicobacter pylori infection is the most common gastrointestinal bacterial disease worldwide. Since antibiotic resistance of H. pylori is increasing and sometimes the cure achieved with antibiotics is not successful, so introduction of new therapeutic agents for treatment or prophylaxis is important. Cumin (Apiaceae family) and tarragon (Asteraceae family) are plants that are native to Iran and it has been reported they are traditionally beneficial in gastric problems . In this study their activity against H. pylori were examined. Percolated methanol and aqueous extracts of plant leaves were examined against 45 clinical isolated of H. pylori. Growth inhibition was determined by the filter paper disc diffusion method on Mueller-Hinton agar containing egg yolk emulsion  compared with amoxicillin and metronidazole standard discs . The effect of both methanol extracts was significantly higher than that of the aqueous extracts (P<0.001). Methanol extract of tarragon and aqueous extract of cumin exhibited the most and the least anti- Helicobacter pylori activity, respectively. The minimum inhibitory concentrations (MICs) of methanol extract of cumin and tarragon were 691µg/ml. Both of the two methanolic extracts preserved their anti- Helicobacter pylori activity after autoclaving for 20min. Preliminary phytochemical screening of the cumin methanol extract indicated the presence of saponins and of the tarragon methanol extract indicated presence of saponins and tannins. This study demonstrated that tarragon and cumin leaves inhibited the growth of H. pylori strains in vitro.
Acknowledgements: This study was supported by Islamic Azad University, Mashhad Branch, Iran for the Scientific Research Project.
References: 1. Zargari A, (1997) Medicinal plants. Tehran University Press. Iran.
2. Tabak M, et al. (1999), J. Ethnopharmacol. 67(3): 269–77.
3. McNulty C, et al. (2002)J. Antimicrob. Chemother. 49: 601–4.