Origanum minutiflorum as a potential therapy for the eradication of Helicobacter Pylori

Helicobacter pylori is a gram negative, spiral shaped, microaerophilic bacterium which colonizes the human stomach of more than half of the world?s population. H. pylori infection plays a crucial role in the pathogenesis of peptic ulcer, gastritis, and gastric cancer. Infection of H. pylori treatment consists of a proton pump inhibitor (PPI) with a combination of antibiotics. This study aims to investigate the potential use of commercial extracts of Siberian ginseng (Eleutherococcus senticosus), Black cohosh (Cimicifuga racemosa), Red clover (Trifolium pratense), Milk thistle (Silybum marianum) and various extracts (methanol, ethanol, aqueous, essential oil) of a Turkish endemic plant Origanum minutiflorum for the eradication of H. pylori. Methanol, ethanol, aqueous and essential oil (EO) extracts of O. minutiflorum were collected via soxhlet extractor and clevenger apparatus. The anti-bacterial activity (agar well diffusion method) and the minimum bactericidal concentration (MBC) of all extracts were determined according to CLSI protocols. The chemical composition of the extract showing the strongest antimicrobial activity was determined via gas chromotography mass spectrom (GC-MS). The cell viability effects of the chosen extract were determined on AGS (human adenocarcinoma) cell line by WST-1 assay for 24, 48, and 72 hours. H. pylori adhesion and invasion of cultured cells was carried out using a standard gentamicin assay at 1/20,000- 1/40,000 (v/v) dilutions of O. minutiflorum EO. Examination of effect of O. minutiflorum EO on H. pylori and H. pylori infected cells were done by scanning electron microscopy (SEM). The results of in vitro studies indicated that the EO extract of O. minutiflorum (92 µg/ml) displayed the strongest antimicrobial effect against H. pylori (ZI= ?90) in comparison to all other plant extracts. The major compound of the EO was determined as carvacrol (29.22 %). The MBC was observed at a concentration of 46 µg/ml (equal to 1/20,000 (v/v) dilution) EO. The MBC value of EO did not show any cytotoxic effect against AGS cells and exhibited a reduction of more than 80 % H. pylori adhered or invaded AGS cells. The findings of this study show the potential future use of O. minutiflorum EO as an alternative therapy to antibiotics for treatment of H. pylori infections.