Antibacterial and Antibiofilm Activity of Lactic Acid Bacteria Isolated from Traditional Artisanal Milk Cheese from Northeast China Against Enteropathogenic Bacteria

The present study aims to investigate the probiotic properties of novel strains of lactic acid bacteria isolated from traditional artisanal milk cheese from Northeast China and to explore their antibacterial activity against enteropathogenic bacteria. Of the 321 isolates, 86 exhibited survival in low pH, resistance to pancreatin, and tolerance to bile salts; of these, 12 inhibited the growth of more than seven enteropathogenic bacteria and exhibited antibiofilm activities against Staphylococcus aureus CMCC26003 and/or Escherichia coli CVCC230. Based on 16S ribosomal RNA sequence analysis, the 12 isolates were assigned to Lactobacillus plantarum (7), Lactobacillus helveticus (3), Pediococcus acidilactici (1), and Enterococcus faecium (1) species. In addition, 5 of the 12 strains were susceptible to most of the tested antibiotics. Furthermore, four strains with sensitivity to antibiotics showed significantly high levels of hydrophobicity similar to or better than the reference strain Lactobacillus rhamnosus GG. Moreover, three strains were confirmed safe through non-hemolytic activities and bacterial translocation. Overall, the selected Lact. plantarum 27053 and 27172 and Lact. helveticus 27058 strains can be considered potential probiotic strains and candidates for further application in functional food and prevention or treatment of gastrointestinal diseases.