## 2 Results
### Experimental Procedure  
Extracts obtained by CE and HVED were analyzed for changes during the extraction, therefore, physical and chemical parameters of extracts were measured. Physical parameter results, including pH, conductivity, temperature and power used for HVED treatment, are given in Table 3. Also, cell disintegration index (\(Z_{\text{p}}\)) was calculated. Furthermore, chemical analyses of wild thyme extracts were performed. In order to compare extraction efficiency of BACs by means of HVED, compared to CE, obtained extracts were analyzed by spectrophotometric methods--total phenolic content (TPC) and antioxidant activity (2,2-diphenyl-2-picrylhydrazyl (DPPPH) free radical assay and ferric reducing antioxidant power (FRAP) assay). Results are given in Figure 2. Extraction yields are presented as g GAE/g of sample \(\times\) 100 and expressed as percentages (%). In order to quantify individual phenolic compounds, an ultra performance liquid chromatography-tandem mass spectrometry characterization (UPLC-MS/MS) analysis was performed. Wild thyme extracts were analyzed for apigenin, carnosol, diosmetin, hydroxytyrosol, luteolin, oleanolic acid, quercetin, rosmarinic acid, p-cymene, thymol, carvacrol and camphor, results are given in Table 4.  
Figure 1: Biplot of the principal component analysis applied on data based on theoretical prediction models including (i) evaluated compounds (marked blue) and (ii) Hansen solubility parameters and COSMO-RS parameters (marked red). H-Hansen solubility parameters, C-COSMO-RS parameters, 1—\(n\)-hexane, 2—ethyl acetate, 3—methyl acetate, 4—ethyloleate, 5—ethanol, 6—1-butanol, 7—isopropanol, 8—methanol, 9—limonene, 10—\(\alpha\)-pinene, 11—cymene, 12—\(\beta\)-myrcene, 13—cyclopentyl methyl ether, 14—dimethylcarbonate, 15—2-methyltetrahydrooffuran, 16—water. Figure 2: Determination of bioactive compounds—total phenolic compounds (TPC) values, antioxidant activity (DPPH, FRAP) and yield—measurements for CE and HVED treated samples when: (**a**) water was used as a solvent, (**b**) 25% ethanol was used as a solvent, (**c**) 50% ethanol was used as a solvent. Extraction type: CE—conventional extraction, N2—HVED extraction with nitrogen, Ar-HVED extraction with argon. \begin{table}
\begin{tabular}{c c c c c c c c c c c c c} \hline \hline \multirow{2}{*}{**Sample**} & \multicolumn{6}{c}{**Concentration (ng/mL)**} & \multirow{2}{*}{**Extraction**} \\ \cline{2-2} \cline{4-11}  & & & **Apigenin** & **Comosol** & **Disomenin** & **Hydroystrosel** & **Luteolin** & **Aclcli** & **Quercetin** & **Rosaminic** & **Acli** & **p-Cymene** & **Thylmol** & **Carvacrol** & **Camphor** & **Type** \\ \hline
3 70 & 12.114 & 0.101 & 31.051 & 12.543 & 101.718 & 4.920 & 0.220 & 3611.057 & 0.147 & 0.100 & 0.023 & 0.497 \\ \hline
9 70 & N/D & 0.546 & N/D & 49.436 & N/D & 58.755 & N/D & 1.983 & 1.255 & 0.023 & 0.003 & 1.177 \\ \hline
3 725 & N/D & 0.284 & 3.851 & 53.034 & 1.109 & N/D & 1.073 & 1050.120 & 0.018 & 0.857 & 0.003 & 0.145 \\ \hline
9 725 & 45.879 & 0.273 & 32.355 & 27.798 & 226.458 & N/D & 1.794 & 6010.666 & 1.149 & 0.010 & 0.098 & 0.138 \\ \hline
3 750 & 66.073 & 0.354 & 28.432 & 14.164 & 170.078 & 458.380 & 1.616 & 4665.132 & 0.029 & 0.041 & N/D & 10.301 \\ \hline
9 750 & 105.846 & 3.491 & 54.155 & 33.044 & 318.747 & 810.724 & 44.725 & 5906.846 & 0.926 & 0.001 & 0.001 & 15.601 \\ \hline \hline \end{tabular} N/D – not detected.  
\end{table} 
Table 4: UPLC-MS/MS analysis of extractive compounds from thyme (measurements for CE and HVED treated samples) (ng/mL).