In vitro antimicrobial activity of Salvadora persica extract on Helicobacter pylori strains isolated from duodenal ulcer biopsies

Abstract

The aim of this study was to evaluate the <em>in vitro</em> antimicrobial activity of a methanolic extract of <em>Salvadora persica</em> solution on <em>Helicobacter pylori</em> isolated from duodenal ulcer. Over 22 strains of H. pylori were isolated from duodenal ulcer from August 2010 to June 2011. The <em>S. persica</em> stem was purchased from a local herb market and finely powdered. Extraction was performed with 60% methanol using a soxhlet extractor for 48 h until the solvent turned colorless while being incubated in an oven at 40°C for 48 h till dried. Dry powder was used to determine antimicrobial activity by the agar ditch method. Minimum inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of the extract were determined by the agar dilution method. At concentrations of 10, 100, 200, 500 µg/mL, no zone of inhibition around the ditches was observed while a clear zone of inhibition (12 mm) was detected at 1000 µg/mL concentration for all the isolates. The best antimicrobial activity was observed at MIC 1000 µg/mL (P≤0.05). Furthermore, 10 out of 22 isolates were inhibited at 750 µg/mL of the extract. The MBC results showed that at a concentration of 1000 µg/mL all cells were dead while at a concentration of 750 µg/mL of<em> S. persica </em>a few <em>H. pylori</em> cells were still able to form colonies on Brucella agar supplemented with sheep red blood cells and antibiotics. From the above results it can be concluded that high concentration of S.persica could inhibit the growth of H. pylori and MIC and MBC were similar at that concentration.