Antibacterial Effects of Bacteriocin secreted by Lactobacillus reuteri against pathogenic Helicobacter pylori

BACKGROUND AND OBJECTIVESHelicobacter pylori causes gastritis, ulcers and gastric cancer. H. pylori has infected more than ۵۰% of the population worldwide. Due to the side effects of antibiotics and strains resistance, the disadvantages of this type of treatment will be greater than its benefits. Reducing H. pylori in the stomach by selective interaction of bacterial cells as an effective method to compete with stomach pathogens is optimal and it may be effective as a blockage in the treatment of H. pyloriMATERIALS AND METHODS In this study, various samples of dairy products in different parts of the country were used to isolate the L. reuteri strain. Microscopic observation, biochemical and molecular tests and sequencing were performed to confirm the strain. Molecular and biochemical tests were performed to H. pylori identification. Anti-Helicobacter pylori activity of Lactobacillus strains by three cell-free supernatant (CFS) types was detected. Activity of non-neutralized and non-heat-treated (CFSs۱), non-neutralized and heat-treated (CFSs۲), pH neutralized and non-heat-treated (CFSs۳) against H. pylori strains was evaluated. Inhibition zone test for H. pylori was performed using L. reuteri strains. lactic acid produced by L. reuteri was neutralized.RESULTS AND DISCUSSION An agar-well diffusion method was used to assess CFS effect on H. pylori growth. The inhibition zones of high concentrations of CFSs were more obvious, indicating that CFS had the potential ability to inhibit H. pylori growth. According to results, the agar-well diffusion test showed significant inhibitory effects of L. reuteri against H. Pylori. Formation of inhibition zone was significantly due to presence of antimicrobial metabolites (e.g. bacteriocin) not secretive acid lactic.CONCLUSION In summary, based on these results it can be found that the L. reuteri which is a probiotic can be applied in therapeutic application for treatment of disease related to H. pylori in gastrointestinal tract. Bacteriocin-like inhibitory substance activity can be an advantage for the probiotic choice for H. pylori infection control. If bacteriocin produced by L. reuteri has antimicrobial properties against Helicobacter pylori, it can be considered as a new generation of probiotics, postbiotics

کلیدواژه ها:

L. reuteri ، H. pylori ، bacteriocin ، agar-well diffusion ، postbiotic