## 3 Results
### Antagonistic Activity of Lactic Acid Bacteria  
Table 11 (in Appendix A) and Figure 1 show the antagonistic activity of lactic acid bacteria against _Staphylococcus_ spp. strains. The tested LAB showed a high antagonistic potential against the test bacteria of the _Staphylococcus_ genus. Both the _S. aureus_ ATCC 25923 and _S. epidermidis_ DSMZ 3270 reference strains were sensitive to the metabolites of the LABs used. The growth inhibition zone for the ATCC 25923 strain was from 14.33 \(\pm\) 0.58 mm to 21.00 \(\pm\) 0.00 mm, while for the DSMZ 3270 strain, the values ranged from 17.22 \(\pm\) 0.58 mm to 20.33 \(\pm\) 0.58 mm. When analyzing the sensitivity of the environmental test strains of _Staphylococcus_ spp. to the metabolites of the LAB tested, it was noted that the R1A strain showed resistance to the metabolites of two lactic acid bacteria strains: _Lacticaseobacillus_ rhomosus_ LOCK 0943 and _Levilactobacillus brevis_ MG451814. In the case of the _Levilactobacillus brevis_ MG451814 strain, its antagonistic potential was also limited in relation to the _Staphylococcus_ spp. strains designated as _S. haemolyticus_ R2A and _S. aureus_ S2A. However, in the case of the test strain _S. saprophyticus_ S1A, the strain MG451814 was characterized by the highest antagonistic activity (the zone of growth inhibition was 50.00 \(\pm\) 0.00 mm). Moreover, it was found that the S1A strain was characterized by a higher sensitivity to the metabolites of the LAB bacteria studied (mean value of the growth inhibition, statistically significant) compared with the remaining _Staphylococcus_ spp. \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Strain or Extract**} & \multicolumn{4}{c}{**MIC of Polyphenols (mg/mL)**} \\ \cline{2-5}  & **AC** & **AP** & **EC** & **EP** \\ \hline _S. aureus_ ATCC 25923 & 0.313 & 0.156 & 0.625 & 0.156 \\ _S. epidermidis_ DSMZ 3270 & 0.313 & 0.313 & 0.313 & 0.156 \\ _S. epidermidis_ R1A & 0.313 & 0.156 & \textgreater{}2.5 & \textgreater{}2.5 \\ _S. haemolyticus_ R2A & 0.313 & 0.313 & 0.156 & 0.313 \\ _S. saprophyticus_ R3A & 0.625 & 0.313 & 0.625 & 0.313 \\ _S. saprophyticus_ S1A & 0.313 & 0.156 & 0.156 & 0.156 \\ _S. aureus_ S2A & 0.625 & 0.625 & 0.625 & 0.625 \\ \hline \hline \end{tabular}  
MIC = minimum concentration of polyphenols, AC = water-acetone crude extract, AP = water-acetone purified extract, EC = water-ethanol crude extract, and EP = water-ethanol purified extract.  
\end{table} 
Table 3: The minimum concentrations of polyphenols that inhibit the growth of _Staphylococcus_ bacteria. Figure 1: _Cont_. Figure 1: Antagonistic activity of lactic acid bacteria and two-component LR systems against environmental isolates of the genus _Staphylococcus_. \(\square\): LR system with the addition of crude extracts; \(\square\): LR system with the addition of purified extracts; \(\square\): LAB basic culture. AC = crude water-acetone extract, AO = purified water-acetone extract, EC = crude water-ethanol extract, and EO = purified water-ethanol extract. (**a**,**c**,**e**,**g**,**i**) Antagonistic activity of two-component LR systems with the addition of acetone extracts and antagonistic activity of LAB stock culture. (**b**,**d**,**f**,**h**,**j**) Antagonistic activity of two-component LR systems with the addition of ethanol extracts and antagonistic activity of LAB stock culture. Lactic acid bacteria: _Lactobacillus acidophilus_ LOCK 0928, _Lacticasibacillus rhamn_s LOCK 0943, _Levilactobacillus brevis_ LOCK 0944, _Lacticasibacillus case_ LOCK 0979, _Levilactobacillus brevis_ LOCK 0980, _Levilactobacillus brevis_ LOCK 0992, and _Levilactobacillus brevis_ MG451814. Bacteria of the genus _Staphylococcus_ spp. R1A: _S. epidermidis_ R1A; R2A: _S. haemolyticus_ R2A; R3A: _S. saprophyticus_ R3A; S1A: _S. saprophlyticus_ S1A; S2A: _S. aureus_ S2A). In the case of the _S. haemolyticus_ R2A strain, it was not possible to clearly define which two-component LR system had the highest and lowest anti-staphylococcal potentials (Figure 1c,d).