## 4 Discussion
According to [PERSON] [35], strains of _Lactobacillus_ spp. other than Biogarde or Bioghurt cultures were used in the production of the tested yoghurts, showing that the correct labeling of the yoghurts was not used in all cases. In our study, the MALDI TOF MS method was used to identify LAB. Different results regarding the manufacturer's declared composition may be due to the use of other starter cultures. Fermented dairy products are characterized by health-promoting properties due to the presence of LAB, mainly of the genus _Lactobacillus_. Bacteria of the genus _Lactobacillus_ are characterized by the production of compounds with antimicrobial activity (lactic acid, organic acids, hydrogen peroxide (H\({}_{2}\)O\({}_{2}\)) or bacteriocins). LAB, through antagonistic interactions with pathogenic bacteria, maintain the gastrointestinal ecosystem in a healthy state [36]. Another aspect studied was the antimicrobial effect of _Lactobacillus_ spp. isolated from the tested yoghurt on foodborne pathogenic bacteria. Our results showed that in the presence of _Lactobacillus_ spp., there is a decrease in the number of pathogenic microorganisms (_E. coli_, _L. monocytogenes_ and _S. Enteritidis). Similar results were obtained by [PERSON] et al. [37], [PERSON] et al. [38], [PERSON] et al. [39] and [PERSON] et al. [40]. We have shown that different species of the genus _Lactobacillus_ caused a different decrease in pathogen abundance. In the single variant (one strain of _Lactobacillus_ spp. ), a greater decrease in pathogenic microorganisms occurred in _L. paracasei_ culture than in _L. rhamnus_. We showed the highest reduction in the number of _L. monocytogenes_ after 72 h of culture with _L. rhamnus_. [PERSON] et al. [41] confirmed the antagonistic effect of _L. rhamnus_ on _L. monocytogenes_. The researchers [41] also showed reduced survival, adhesion and invasiveness of the _L. monocytogenes_ strains tested, but they did not explain the basis of this mechanism. In turn, [PERSON] et al. [42] confirmed the effect of _L. rhamnus_ on reducing the number of _L. monocytogenes_ cheese surface, with no effect of this strain on _Staphylococcus aureus_. In contrast, a study by [PERSON] et al. [43] showed that _L. rhamnus_ supernatant inhibited biofilm formation by _L. monocytogenes_. [PERSON] et al. [42] and [PERSON] et al. [43] also failed to explain the differences in the antagonistic effects of _L. rhamnus_. We showed that _L. rhamnus_ had the least effect on reducing _E. coli_ and _S. Enteritidis._ In contrast, [PERSON] et al. [44] demonstrated that _L. rhamnus_ had the effect of reducing the number of _E. coli_, _Listeria innocua_ and _Staphylococcus epidermidis_. In turn, [PERSON] et al. [45] tested three strains of _L. rhamnus_ (isolated from a mare's milk). The researchers confirmed the activity of LAB against _S. Typhimurium, Shigella sonnei, L. monocytogenes_ and _E. coli_ [45]. In contrast, [PERSON] et al. [46] confirmed the antagonistic effect of _L. rhamnus_ SQ511 on _S. Enteritidis._ Researchers [46] showed that antimicrobial compounds produced by _L. rhamnus_ SQ511 caused a significant inhibition of growth, biofilm-forming ability, mobility, changes in the expression of the selected virulence genes and disruption of the integrity of _S. Enteritidis. We showed that after 72 h of culture with _L. paracasei_, the highest decrease was observed for _S. Enteritidis. The inhibitory effect of LAB (including _L. bulgaricus_, _L. rhamnus_ and _L. paracasei_) on _Salmonella_ spp. was demonstrated by [PERSON] and [PERSON] [47]. The researchers [47] showed that LAB affect the reduction in _Salmonella_ spp. (including multidrug-resistantstrains) by modulating their gene expression. However, in our study, the greatest reduction in pathogenic bacteria counts occurred in the mixed culture (_L. rhamnus + L. paracasei_). The mixed culture reduced the number of \(S\). Enteritidis. Similar studies were conducted by [PERSON] et al. [44], [PERSON] et al. [48] and [PERSON] et al. [45]. [PERSON] et al.