Isolation and characteristics of lactic acid bacteria with antibacterial activity against Helicobacter pylori

Abstract With the advantages of superior antibacterial activity and probiotic performance, lactic acid bacteria have been attracting considerable attention in the inhibition of Helicobacter pylori. Here, five Lactiplantibacillus plantarum strains were isolated by a multi-step method and characterized in cell adhesion, β-glucosidase activity, antibiotic susceptibility and hemolytic activity. The five strains supernatants can reduce the viable counts of Helicobacter pylori from 7.4 × 108 CFU/mL to 1.5 × 104–2.0 × 105 CFU/mL after treating for 8 h. The five stains supernatants also showed a better inhibitory effect in the urease activity than the other strains, with the decreased activity of 84.3–90.2% and 73.2–84.0% when treated with the supernatants and the strains for 6 h, respectively. The adhesion of Iso05 to GES-1 cells was up to 9.1%, significantly superior to that of the other four strains, adhesion rate of which ranged from 2.1% to 6.1%. Furthermore, the five strains can decrease the adhesion of Helicobacter pylori by 66.0–89.7%, and the β-glucosidase activity of the five strains reached 0.10–0.14 U/g wet cells. Finally, the five strains were safe with nonhemolytic activity. This study contributes to the isolation of lactic acid bacteria with anti-Helicobacter pylori ability and the development of antibiotics-free anti-Helicobacter pylori foods.