## 3 Results and Discussion  
### Physical-Chemical Parameters of the Essential Oils  
The physical-chemical properties of the investigated essential oils are used as quality parameters according to recommendations established by the European Pharmacopoeia and International Standards. Physical-chemical parameters of the investigated essential oils are presented in Table 3.  
The chemical compositions of the essential oils evaluated by GC-MS are presented in Table 4. \begin{table}
\begin{tabular}{c c c} \hline \hline
**No.** & **Microbial Strain** & **Source** \\ \hline
**1** & _Staphylococcus aureus_ & Gram-positive standard strain, The microorganism collection of the Microbiology, ATCC 25923 & Department, Faculty of Biology, University of Bucharest \\ \hline
**2** & _Pseudomonas aeruginosa_ & Gram-negative standard strain, The microorganism collection of the Microbiology, ATCC 27853 & Department, Faculty of Biology, University of Bucharest \\ \hline
**3** & _Escherichia coli_ & Gram-negative standard strain, The microorganism collection of the Microbiology, ATCC 25922 & Department, Faculty of Biology, University of Bucharest \\ \hline
**4** & _Candidida albicans_ & Yeast standard strain, The microorganism collection of the Microbiology, Department, ATCC 10231 & Faculty of Biology, University of Bucharest \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Standard microbial strains used for testing antimicrobial activities. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Compounds**} & \multirow{2}{*}{**Classes**} & \multicolumn{2}{c}{**Eucalyptus**} & \multicolumn{2}{c}{**Thyme**} & \multicolumn{2}{c}{**Pine**} & \multicolumn{1}{c}{**Sage**} & \multicolumn{1}{c}{**Femnel**} \\  & & **EO** & **EO** & **EO** & **EO** & **EO** & **EO** \\ \hline \(\beta\)**-Pinene** & MT & 0.36 & - & 30.21 & 1.77 & - \\ \hline \(\alpha\)**-Phellandrene** & MT & 0.51 & - & - & - & 5.66 \\ \hline \(\beta\)**-Phellandrene** & MT & - & - & 0.60 & - & - \\ \hline \(\beta\)**-Myrcene** & MT & 0.26 & 0.62 & 2.81 & 0.66 & - \\ \hline \(\text{D-Limonene}\) & MT & 8.82 & 0.47 & 18.92 & 1.67 & - \\ \hline \(\text{Eucalypt}\) & MT & 82.10 & - & - & 7.27 & - \\ \hline \(\gamma\)**-Terpinene** & MT & 3.36 & 0.29 & - & 0.39 & - \\ \hline \(\text{p-Cymene}\) & MT & 4.59 & 35.10 & 3.61 & 0.68 & - \\ \hline \(\text{Camphene}\) & MT & - & 0.71 & 3.15 & 4.28 & - \\ \hline \(\text{Pinocarvone}\) & MT & - & 2.08 & - & - & - \\ \hline \(\beta\)**-Caryophyllene** & ST & - & 2.21 & 3.68 & 3.51 & - \\ \hline \(\alpha\)**-Caryophyllene** & ST & - & - & - & 4.44 & - \\ \hline \(\text{Carvacrol}\) & MT & - & 58.52 & - & - & - \\ \hline \(\text{Fenchone}\) & MT & - & - & - & - & 11.91 \\ \hline \(\text{Estragole}\) & PP & - & - & - & - & 2.97 \\ \hline \(\text{Anethole}\) & PP & - & - & - & - & 79.46 \\ \hline \(\text{Carene}\) & MT & - & - & 29.08 & - & - \\ \hline \(\text{Terpinolene}\) & MT & - & - & 0.59 & 0.25 & - \\ \hline \(\text{Longifolene}\) & ST & - & - & 2.72 & - & - \\ \hline \(\text{Bornyl acetate}\) & MT & - & - & 3.05 & - & - \\ \hline \(\alpha\)**-Terpineol** & MT & - & - & 1.59 & - & - \\ \hline \(\text{Thujone}\) & MT & - & - & - & 38.92 & - \\ \hline \(\text{Isothujone}\) & MT & - & - & - & 6.19 & - \\ \hline \((+)\)-2-Bornanone & MT & - & - & - & 21.32 & - \\ \hline \(\text{Linalool}\) & MT & - & - & - & 0.72 & - \\ \hline \(\text{Borneol acetate}\) & MT & - & - & - & 1.01 & - \\ \hline \(\text{Terpinen-4-ol}\) & MT & - & - & - & 0.56 & - \\ \hline \((-)\)**Borneol** & MT & - & - & - & 2.55 & - \\ \hline \(\text{Viridiflorol}\) & ST & - & - & - & 3.82 & - \\ \hline \(\text{Monoterpene (MT)}\) & & 100 & 97.79 & 93.6 & 88.23 & 17.57 \\ \(\text{Sesquirepene (ST)}\) & & - & 2.21 & 6.4 & 11.77 & - \\ \(\text{Phenylpropanoids (PP)}\) & & - & - & - & - & 82.43 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Main constituents of investigated essential oils.