# Functional and Antimicrobial Properties of Propolis from Different Areas of Romania
## 3 Results
### Antimicrobial Activity and MIC
With regard to _L. monocytogenes_ ATCC 35152, it is evident that there is considerable variability among the various extracts. C1 exhibited the lowest efficacy, with a mean of 0.50 mg/mL, whereas the least effective extract was H, which displayed a mean value of 5.63 mg/mL. The results of the MIC test demonstrate that the efficacy of these extracts is diminished in comparison to the pathogens that were tested, particularly in relation to Gram-negative bacteria. With regard to the _K. pneumoniae_ ATCC 13883, sensitivity was observed in samples A and S, with mean values of 8.13 mg/mL, followed by samples C1 and C2, which exhibited \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline  & **C1** & **C2** & **A** & **S** & **H** & **PC** \\ \hline \multirow{8}{*}{**Gram-positive strains**} & _E. faecalis_ & \multirow{2}{*}{0.75} & \multirow{2}{*}{1.00} & \multirow{2}{*}{1.78} & \multirow{2}{*}{3.12} & \multirow{2}{*}{4.06} & \multirow{2}{*}{1.56 \(\times\) 10\({}^{-3}\)} \\  & **ATCC 29212** & & & & & & \\ \cline{2-7}  & _S. aureus_ & \multirow{2}{*}{0.45} & \multirow{2}{*}{0.25} & \multirow{2}{*}{0.45} & \multirow{2}{*}{0.78} & \multirow{2}{*}{0.78} & \multirow{2}{*}{6.25 \(\times\) 10\({}^{-3}\)} \\  & **ATCC 25923** & & & & & & \\ \cline{2-7}  & _S. aureus_MRSA & \multirow{2}{*}{1.00} & \multirow{2}{*}{0.59} & \multirow{2}{*}{0.89} & \multirow{2}{*}{2.56} & \multirow{2}{*}{4.06} & \multirow{2}{*}{12.5 \(\times\) 10\({}^{-3}\)} \\  & **ATCC 43300** & & & & & & \\ \cline{2-7}  & _S. epidermidis_ & \multirow{2}{*}{0.59} & \multirow{2}{*}{1.28} & \multirow{2}{*}{1.00} & \multirow{2}{*}{3.12} & \multirow{2}{*}{4.06} & \multirow{2}{*}{6.25 \(\times\) 10\({}^{-3}\)} \\  & **ATCC 12228** & & & & & & \\ \cline{2-7}  & _L. monocytogenes_ & \multirow{2}{*}{0.50} & \multirow{2}{*}{1.28} & \multirow{2}{*}{1.78} & \multirow{2}{*}{4.69} & \multirow{2}{*}{5.63} & \multirow{2}{*}{3.12 \(\times\) 10\({}^{-3}\)} \\  & **ATCC 35152** & & & & & & \\ \hline \multirow{8}{*}{**Gram-negative strains**} & _K. pneumoniae_ & \multirow{2}{*}{12.50} & \multirow{2}{*}{12.50} & \multirow{2}{*}{8.13} & \multirow{2}{*}{8.13} & \multirow{2}{*}{R} & \multirow{2}{*}{6.25 \(\times\) 10\({}^{-3}\)} \\  & **ATCC 13883** & & & & & & \\ \cline{2-7}  & _E. coli_ & \multirow{2}{*}{1.56} & \multirow{2}{*}{0.78} & \multirow{2}{*}{3.12} & \multirow{2}{*}{5.63} & \multirow{2}{*}{11.25} & \multirow{2}{*}{1.56 \(\times\) 10\({}^{-3}\)} \\  & **ATCC 25922** & & & & & & \\ \cline{2-7}  & _P. aeruginosa_ & \multirow{2}{*}{5.63} & \multirow{2}{*}{2.56} & \multirow{2}{*}{8.13} & \multirow{2}{*}{12.50} & \multirow{2}{*}{18.75} & \multirow{2}{*}{6.25 \(\times\) 10\({}^{-3}\)} \\  & **ATCC 27853** & & & & & & \\ \cline{2-7}  & _S. enterica_ & \multirow{2}{*}{2.56} & \multirow{2}{*}{1.28} & \multirow{2}{*}{3.12} & \multirow{2}{*}{5.63} & \multirow{2}{*}{5.63} & \multirow{2}{*}{3.12 \(\times\) 10\({}^{-3}\)} \\  & **ATCC 25928** & & & & & & \\ \cline{2-7}  & _A. baumannii_ & \multirow{2}{*}{6.25} & \multirow{2}{*}{8.13} & \multirow{2}{*}{11.25} & \multirow{2}{*}{11.25} & \multirow{2}{*}{12.50} & \multirow{2}{*}{6.25 \(\times\) 10\({}^{-3}\)} \\  & **ATCC 19606** & & & & & & \\ \hline \multirow{2}{*}{**Yeast strain**} & _C. albicans_ & \multirow{2}{*}{0.39} & \multirow{2}{*}{0.39} & \multirow{2}{*}{1.03} & \multirow{2}{*}{1.28} & \multirow{2}{*}{1.50} & \multirow{2}{*}{3.12 \(\times\) 10\({}^{-3}\)} \\  & **ATCC 10231** & & & & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 10: Minimum inhibitory concentration of the five propolis ethanolic extracts against the tested bacterial and yeast strains. Data are expressed as the mean value (\(n=3\)) and as mg/mL. a mean value of 12.5 mg/mL. Extract H did not respond to the concentrations that were tested. In the case of the _E. coli_ ATCC 25922, an increased sensitivity was observed for the extract derived from C2 (0.78 mg/mL), followed by C1 (1.56 mg/mL).