## 3 Results
### Recovery Ratio of Bacteria from Contaminated Samples
jejuni_ ranged from 3.393 log CFU \(\times\) cm\({}^{-2}\) (ATCC strain) to 3.668 log CFU \(\times\) cm\({}^{-2}\) (strain 2), _L. monocytogenes_ from 3.587 log CFU \(\times\) cm\({}^{-2}\) (strain 2) to 4.585 log CFU \(\times\) cm\({}^{-2}\) (ATCC strain), and _S._ Enteritidis from 3.614 log CFU \(\times\) cm\({}^{-2}\) (for strain 2) to 3.880 log CFU \(\times\) cm\({}^{-2}\) (strain 1). Significant differences between strains of the same species were observed in the case of _L. monocytogenes_ reference strain and strain 2. The reduction of the _S._ Enteritidis number was significantly higher than that observed for _C. jejuni_ and _L. monocytogenes_ (Figure 4). The reduction of bacteria number (R) in the biofilm formed on the non-RCI-treated glass surface ranged from 0.002 to 0.008. High effectiveness of RCI application was confirmed by the obtained reduction rate values, ranging from 0.240 (_C. jejuni_) to 0.329 (_L. monocytogenes_). No significant differences were observed between different species (Figure 3). The highest value of the absolute RCI efficiency coefficient (0.409) was noted for _L. monocytogenes_ strain 2; however, it was not statistically significantly higher than those calculated for two other strains of this species. On the contrary, absolute RCI efficiency coefficients calculated for _C. jejuni_ strains 1 and 2 (0.173 and 0.150, respectively) were statistically significantly lower, as compared with _C. jejuni_ reference strain (0.375), _L monocytogenes_ strains 1 and 2, and S. Enteritidis strain 2 (0.306, 0.409, and 0.302, respectively). No significant differences in the RCI absolute efficiency coefficient were observed for _S._ Enteritidis strains (Table 1). Figure 4: The average number of _Campylobacter jejuni_ (CJE), _Listeria monocytogenes_ (LMO), and _Salmonella_ Enteritidis (SENT) isolated from the contaminated meat sample (M), glass surface after contact with the meat sample (I), non-RCI-treated (-RCI) glass surface, RCI-treated (RCI+) glass surface in the experimental variant II (a,b,c—values marked with different letters differ statistically significantly). Assessment of Effectiveness of Surface Disinfection Using Radiant Catalytic Ionization during Biofilm Formation (Experimental Variant III)  
The average number of bacteria reisolated from the glass surface not treated with RCI was 5.472 log CFU \(\times\) cm\({}^{-2}\), 6.124 log CFU \(\times\) cm\({}^{-2}\), and 5.162 log CFU \(\times\) cm\({}^{-2}\) for _C. jejuni_, _L. monocytogenes_, and _S._ Enteritidis, respectively (Figure 5). The number of bacteria for _C. jejuni_ ranged from 5.526 log CFU \(\times\) cm\({}^{-2}\) (ATCC strain) to 5.439 log CFU \(\times\) cm\({}^{-2}\) (strain 2), for _L. monocytogenes_ from 6.060 log CFU \(\times\) cm\({}^{-2}\) (strain 2) to 6.166 log CFU \(\times\) cm\({}^{-2}\) (ATCC strain), and for _S._ Enteritidis from 5.091 log CFU \(\times\) cm\({}^{-2}\) (ATCC strain) to 5.211 log CFU \(\times\) cm\({}^{-2}\) (strain 2). The application of radiant catalytic ionization resulted in a decrease of bacteria number, but not statistically significant. The average number of bacteria for _C. jejuni_, _L. monocytogenes_, and _S._ Enteritidis was 4.602 log CFU \(\times\) cm\({}^{-2}\), 5.366 log CFU \(\times\) cm\({}^{-2}\), and 4.647 log CFU \(\times\) cm\({}^{-2}\), respectively. No significant differences between RCI-treated and non-treated samples were observed for all species (Figure 5). The highest bacteria number reduction rate after RCI treatment was observed for _C. jejuni_ strains (0.163) in variant III. _L monocytogenes_ and _S._ Enteritidis reduction rates were 0.127 and 0.089, respectively. The differences in the bacteria number reduction rate between species were not statistically significant (Figure 3). The coefficient of absolute RCI efficiency calculated for the tested bacteria varied from 0.049 (_L. monocytogenes_ strain 1) to 0.171 (_C. jejuni_ strain 2). The E values for _C. jejuni_ strains were statistically significantly higher than those obtained for the remaining strains, excluding _L.