## 3 Results and Discussion
### The Cytotoxicity Tests against C. Albicans  
The cytotoxicity results against _C. albicans_ (Figure 3) demonstrated a gradual increase in the extract concentration. An average value of 47 \(\pm\) 1.63% (\(p\leq\) 0.01) was calculated for an extract of 0.062 mg/mL. These results were interpreted as a functional property of the extract to modulate this strain's proliferation resistance, a relevant fact in the formation of the biofilm and the preservation of urinary tract homeostasis. The antifungal response differences were due to the variable presence of functional compounds that could be correlated with the type of bioactive molecules and biotransformations due to the environment, in vitro [40]. This feature could be considered as a limiting factor of in vitro simulators. This study demonstrated that the proposed in vitro model was a useful tool for managing UTI with _E. coli_. Such a laboratory model can bring the results as close as possible to those obtained in vivo clinical trials [41].  
Figure 2: The antibacterial effect of the product in the in vitro catheterization system. Different asterisks represent significant statistical differences (control vs. samples; \(p\leq\) 0.05), n = 3.  
These results were supported by the presence of quercetin, which was reported to have urinary tract protection effects. Quercetin is used as an adjuvant to conventional treatments [42]. These data support previous studies that have shown a reduction in biofilm formation to about 65% and an inhibition in the proliferation of the _Candida_ genus strains [43]. In addition, these compounds have prevented the formation (synthesis) of the self-produced extracellular matrix that helps build the biofilm and the recurrence of inflammatory processes. These data may have been associated with the action of other compounds, such as myretien or catechin [44].  
Another compound that expressed an antibacterial effect against _E. coli_ was rosmarinic acid. Its action was synergistic in UTIs because an antioxidant effect was also determined. The expression of these effects is a specific one, with the antimicrobial effect being due to an action on the cell membrane [38; 45]. The same mechanism has been demonstrated for ferulic acid [46] and in reducing the microbial biofilm [47] by decreasing the adhesion capacity of bacterial cells. The product's effectiveness was also due to the presence of coumaric acid, which is known to have similar effects in reducing bacterial cells as ferulic acid, the majority component [48]. The presence of these compounds also supported the cytotoxic effect, being correlated with the gradual decrease of the viability of the _Candida_ strain [49].  
Thus, the purpose of the study was achieved, given the inhibitory capacity of the tested extract. Static in vitro tests targeting the current model did not consider urinary epithelial interactions that may influence the bioavailability of specific compounds. This aspect can be viewed as a negative point of this type of study.  
As a practical application, the realization of this model was useful for in vitro research studies that will be able to simulate certain recurrent infections. Testing the formulation of functional products and drugs with antimicrobial effects associated with inhibiting biofilm formation is another research perspective with this model in vitro. Other uropathogenic strains that can be identified with the biofilm associated with the urinary catheter can also  
Figure 3: The cytotoxicity tests against _Candida albicans_. Different asterisks represent significant statistical differences (control vs. samples; \(p\leq 0.05\)), n = 3.  
be tested. New quantification and microbial analysis methods will meet practical needs regarding the presence of bacteria in the urinary tract [50].