## 3 Results and Discussion
### Cell Survival during In Vitro Digestion Model
\begin{table}
\begin{tabular}{c c c c} \hline \hline _L. rhamnus_** **OLXAL-1** & \multicolumn{3}{c}{**Survival Rate (\%)**} \\
**Cell Cultures** & \multicolumn{3}{c}{**Simulated Salivary Phase**} & **Simulated Gastric Phase** & **Simulated Intestinal Phase** \\ \hline Wet immobilized cells on oat flakes & 99.39 \(\pm\) 0.19 \({}^{\text{A}}\) & 88.63 \(\pm\) 0.31 \({}^{\text{Be}}\) & 84.76 \(\pm\) 0.56 \({}^{\text{Cf}}\) \\ Freeze-dried immobilized cells on & 99.22 \(\pm\) 0.46 \({}^{\text{A}}\) & 82.78 \(\pm\) 0.26 \({}^{\text{Ba}}\) & 81.22 \(\pm\) 1.36 \({}^{\text{Bef}}\) \\ Wet immobilized cells on & 98.42 \(\pm\) 0.48 \({}^{\text{A}}\) & 83.05 \(\pm\) 0.19 \({}^{\text{Bab}}\) & 77.66 \(\pm\) 1.94 \({}^{\text{Bde}}\) \\ Freeze-dried immobilized cells on & 99.46 \(\pm\) 0.76 \({}^{\text{A}}\) & 82.43 \(\pm\) 0.37 \({}^{\text{Ba}}\) & 76.08 \(\pm\) 0.46 \({}^{\text{Cd}}\) \\ wheat flakes & 99.09 \(\pm\) 1.59 \({}^{\text{A}}\) & 87.38 \(\pm\) 1.10 \({}^{\text{Bbe}}\) & 51.01 \(\pm\) 0.40 \({}^{\text{Cb}}\) \\ Freeze-dried immobilized cells on & 98.87 \(\pm\) 1.20 \({}^{\text{A}}\) & 83.54 \(\pm\) 0.09 \({}^{\text{Bab}}\) & 48.65 \(\pm\) 1.35 \({}^{\text{Cb}}\) \\ Wet immobilized cells on banana & 98.74 \(\pm\) 0.16 \({}^{\text{A}}\) & 72.13 \(\pm\) 2.36 \({}^{\text{Bd}}\) & 70.01 \(\pm\) 0.32 \({}^{\text{Bc}}\) \\ Freeze-dried immobilized cells on & 98.54 \(\pm\) 0.57 \({}^{\text{A}}\) & 71.49 \(\pm\) 1.22 \({}^{\text{Bd}}\) & 66.80 \(\pm\) 0.18 \({}^{\text{Cc}}\) \\ banana pieces & 99.33 \(\pm\) 0.22 \({}^{\text{A}}\) & 65.74 \(\pm\) 0.10 \({}^{\text{Bc}}\) & 36.29 \(\pm\) 1.35 \({}^{\text{Ca}}\) \\ Wet free cells & 99.23 \(\pm\) 0.77 \({}^{\text{A}}\) & 65.10 \(\pm\) 0.85 \({}^{\text{Bc}}\) & 33.42 \(\pm\) 0.86 \({}^{\text{Ca}}\) \\ \hline \hline \end{tabular} Data are presented as mean \(\pm\) SD. Significant differences (\(p<0.05\)) are denoted by different uppercase letters in superscript (row) and different lowercase letters in superscript (column).  
\end{table} 
Table 1: Tolerance of immobilized and free _L. rhamnus_ **OLXAL-1** cultures to simulated digestion phases. the use of cereals as immobilization supports, various fruits have also been studied for their potential protective effect against simulated GI transit. [PERSON] et al. [41] studied the immobilization of _Lactobacillus casei_ CSL3 on kiwi, guava and pineapple pieces, which were subsequently incorporated into _Petit Suisse_ cheese. Notably, _Petit Suisse_ cheeses with either immobilized or free cells exposed to simulated GI transit conditions did not differ in terms of cell viability, a result that, according to the authors, can be attributed to the ingredients included in the food matrix (cheese) that contributed to the preservation of the probiotic bacteria. According to the abovementioned studies, the observed protective effect of cell immobilization on bacterial cells can be attributed to various factors. One of the primary contributors, which has been highlighted in several studies, is the buffering capacity of ingested food, which transiently increases the pH values in gastric juices, thereby providing a protective shield for probiotic bacteria [36]. Furthermore, the presence of fibers and sugars in cereals and fruits has also been suggested as contributing agents, since they offer an optimal substrate for the growth and survival of LAB [42; 43; 44]. Additionally, it is also suggested that the attachment of cells to the food matrix, or their entrapment within it, acts as a barrier, reducing the susceptibility of probiotics to adverse conditions during GI transit [45]. Nevertheless, to validate these observed protective effects gained from in vitro studies, it is essential to further investigate the effectiveness of cell immobilization on food matrices in a dynamic in vivo model.