## 3 Results
### Antibacterial Activity of Eugenol and Isoeugenol Against Gram-Negative Bacteria
The inhibition zones mea  
\begin{table}
\begin{tabular}{l l c c c c c} \hline \hline  & \multicolumn{2}{c}{**Control**} & \multicolumn{2}{c}{**Control**} & \multirow{2}{*}{**Eugenol (EU)**} & \multirow{2}{*}{**Isoeugenol**ol} & \multirow{2}{*}{**Statistical**} \\  & & **Negative** & & & & & \\  & **(0.9\% NaCl)** & & & & & \\ \hline \multirow{8}{*}{**C**} & mean \(\pm\) SD, & mean \(\pm\) SD, & mean \(\pm\) SD, & mean \(\pm\) SD, & \multirow{2}{*}{**S**} \\  & mm & mm & mm & mm & mm & \\ \cline{2-6}  & K. _pneumoniae_ ATCC & & & & & \\
700603 & 6.0 \(\pm\) 0.0 & 10.0 \(\pm\) 0.0 & 13.4 \(\pm\) 0.5 & 10.0 \(\pm\) 0.0 & - \\ \cline{2-6}  & K. _pneumoniae_ NDM & 6.0 \(\pm\) 0.0 & 12.0 \(\pm\) 0.0 & 15.4 \(\pm\) 0.5 & 14.6 \(\pm\) 0.5 & * \\ \cline{2-6}  & K. _pneumoniae_ ESBL & 6.0 \(\pm\) 0.0 & 15.0 \(\pm\) 0.0 & 15.4 \(\pm\) 0.5 & 15.2 \(\pm\) 0.4 & - \\ \cline{2-6}  & E. _coli_ ATCC 25922 & 6.0 \(\pm\) 0.0 & 14.0 \(\pm\) 0.0 & 15.2 \(\pm\) 0.8 & 13.4 \(\pm\) 0.5 & * \\ \cline{2-6}  & E. _coli_ OSA—48 & 6.0 \(\pm\) 0.0 & 13.0 \(\pm\) 0.0 & 15 \(\pm\) 0.0 & 16.4 \(\pm\) 0.5 & * \\ \cline{2-6}  & E. _coli_ ESBL & 6.0 \(\pm\) 0.0 & 15.0 \(\pm\) 0.0 & 20.4 \(\pm\) 0.9 & 19.2 \(\pm\) 1.1 & - \\ \cline{2-6}  & P. _aeruginosa_ ATCC 27853 & 6.0 \(\pm\) 0.0 & 10.0 \(\pm\) 0.0 & 7.0 \(\pm\) 0.7 & 6.6 \(\pm\) 0.5 & - \\ \cline{2-6}  & P. _aeruginosa_ VIM & 6.0 \(\pm\) 0.0 & 8.0 \(\pm\) 0.0 & 7.2 \(\pm\) 0.4 & 6.0 \(\pm\) 0.0 & - \\ \cline{2-6}  & H. _influenzae_ ATCC 49766 & 6.0 \(\pm\) 0.0 & 15.0 \(\pm\) 0.0 & 24.8 \(\pm\) 0.4 & 20.0 \(\pm\) 0.0 & ** \\ \cline{2-6}  & _A. bbaumanti_ MDR & 6.0 \(\pm\) 0.0 & 15.0 \(\pm\) 0.0 & 19.4 \(\pm\) 0.9 & 13.8 \(\pm\) 0.4 & * \\ \cline{2-6}  & _E. cloaceae_ ESBL & 6.0 \(\pm\) 0.0 & 13.0 \(\pm\) 0.0 & 13.8 \(\pm\) 0.4 & 12.0 \(\pm\) 0.0 & - \\ \cline{2-6}  & _Salmonella_**sp. ** & 6.0 \(\pm\) 0.0 & 14.0 \(\pm\) 0.0 & 16.4 \(\pm\) 0.9 & 16.0 \(\pm\) 0.7 & - \\ \cline{2-6}  & _N. gonorrhoeae_ & 6.0 \(\pm\) 0.0 & 15.0 \(\pm\) 0.0 & 42.0 \(\pm\) 0.4 & 40.0 \(\pm\) 0.5 & * \\ \hline \multicolumn{6}{l}{_the diameter of the sterile disk was 6 mm_} \\ \multicolumn{6}{l}{_Legend:_} \\ \multicolumn{6}{l}{\(\ \sured 7 mm and 7.2 mm, respectively, which are significantly lower than the positive control. The literature indicates that _P. aeruginosa_ frequently develops resistance to many antibiotics, potentially due to decreased outer membrane permeability and the overexpression of efflux systems [16; 17]. This highlights the challenge posed by this pathogen and the need for innovative approaches to enhance the efficacy of eugenol and isoeigenol against such resistant strains. For the _Haemophilus influenzae_ (ATCC 49766) and _Acinetobacter baumannii_ (MDR) strains, good to moderate antibacterial activity was observed, suggesting that these compounds may effectively inhibit the growth of these bacteria. Further investigation into the specific interactions between eugenol, isoeigenol, and the cell membranes of these pathogens could clarify their potential mechanisms of action. Notably, in the case of _Neisseria gonorrhoeae_, both eugenol and isoeigenol exhibited strong antibacterial activity, with the highest inhibition zone measuring 42 mm for eugenol. These results correlate with the literature [17; 18], which also reports the effectiveness of eugenol against _N. gonorrhoeae_. This finding is particularly significant, as _N. gonorrhoeae_ is increasingly reported to develop resistance to conventional antibiotics, underscoring the potential of eugenol and isoeigenol as alternative treatment options. In conclusion, the results obtained from this study confirm the potential of eugenol and isoeigenol as antimicrobial substances, particularly against _N. gonorrhoeae_, _H. influenzae_, and strains from the _Enterobacteriaceae_ family. The findings highlight the necessity for further research to better understand the mechanisms of action of these compounds, including their interactions with bacterial cell membranes and metabolic pathways.