## 3 Results
### Biological Potential
#### 3.3.4 Antimicrobial Activity  
The antimicrobial effectiveness of CNC-CTAB encapsulating CBG, as well as free CBG and the carrier, was assessed against common microorganisms linked to gastrointestinal conditions. Due to the aqueous insolubility of the delivery system, the previously established biocompatible concentrations were evaluated using the incorporation method. The study focused on four reference strains: _Escherichia coli_, _Salmonella enteritidis_, _Listeria innocua_, and _Campylobacter jejuni_, which include both Gram-positive and Gram-negative bacteria. The findings are outlined in Table 2.  
According to Table 2, using the employed method, none of the samples were capable of inhibiting the growth of _Escherichia coli_, _Salmonella enteritidis_, and _Listeria innocua_ at the concentrations tested. CBG has demonstrated antimicrobial activity against various strains, including methicillin-resistant _Staphylococcus aureus_ (MRSA) [41], _Streptococcus mutans_ [42],  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Sample** & _E. coli_ & _S. enteritidis_ & _L. innocua_ & _C. jejuni_ \\ \hline CNC-CTAB\_CBG & \(-\) & \(-\) & \(-\) & \(+\) \\ CBG & \(-\) & \(-\) & \(-\) & \(-\) \\ CNC-CTAB & \(-\) & \(-\) & \(-\) & \(+\) \\ \hline \hline \end{tabular} (–) Absence of antimicrobial activity (microorganism growth present); (+) Antimicrobial activity (inhibition of microorganism growth). Tested strains _were Escherichia coli_, _Salmonella enteritidis_, _Listeria innocua_, and _Campylobacter jejuni_.  
\end{table}
Table 2: Antimicrobial properties of CNC-CTAB loaded with CBG (0.12 g/L), CBG (30 \(\upmu\)M), and CNC-CTAB (0.09 g/L) against four reference microorganisms linked to the gastrointestinal tract.  
Figure 6: Immunomodulatory properties of CNC-CTAB encapsulated CBG, free CBG, the carrier, and betamethasone (positive control) on the Caco-2 cell line, employing IL-18 as a pro-inflammatory stimulus. The findings were assessed against the basal control level, with varying letters indicating significant statistical differences (\(p<0.05\)) among the cytokine responses for each sample.  
Staphylococcus epidermidis, Streptococcus pyogenes, and Propioniferax innocua_[14]. CBG has shown antimicrobial activity by altering bacterial membrane properties, such as membrane hyperpolarization, reduction in fluidity, and increased permeability [42]. However, CBG MIC values of 500 \(\upmu\)M have been observed for _E. coli_[14], which may explain the inability to inhibit microbial growth at the concentration tested (30 \(\upmu\)M). While free CBG had no impact on the growth of _Campylobacter jejuni_ at the tested concentration, free CNC-CTAB and CNC-CTAB loaded with CBG successfully inhibited its growth. Despite the high CBG concentration present in the delivery system, its hydrophobic nature poses challenges to its release within the agar medium. As a result, the antimicrobial outcomes obtained in this study for encapsulated CBG are likely attributed to CNC-CTAB, a view supported by the antimicrobial effect demonstrated by the free carrier material. While CNC itself has not been associated with significant antimicrobial activity [43], the CTAB surfactant has exhibited antimicrobial traits linked to its amphipathic structure's positive charge [44]. The observed antimicrobial effects of CNC-CTAB encapsulating CBG against C. _ jejuni_ hold great promise, particularly in the context of gastrointestinal delivery. _Campylobacter jejuni_ stands out as a leading cause of bacterial enteritis and colonic inflammation, and it has been recognized as one of the most common risk factors for IBDs and irritable bowel syndrome (IBS). Evidence suggests that C. _ jejuni_ disrupts intestinal epithelial structure and function and thereby permits the translocation of luminal material, including resident intestinal bacteria, into the subepithelial compartment, which may prime the intestine for subsequent inflammation [45].