## 4 Conclusions
\begin{table}
\begin{tabular}{c c c c c c c c c c c c} \hline \hline
**No** & **Compound \({}^{*}\)** & **Class** & **AL** & **CH** & **HU** & **LO\_S** & **LO\_N** & **LI** & **PI** & **TO** & **VE** \\ \hline
1 & oxalic acid 6-ethyloct-3-yl ethyl ester & ester & & & & & & & & & \(\bullet\) & \(\bullet\) \\
2 & 3-(3,4-dimethoxyyphenyl)-6- & & aromatic & & & & & & & & & \(\bullet\) \\  & nitrocoumarin & & & & & & & & & & & \(\bullet\) \\
3 & methoxyacetic acid 2-tetradecyl ester & ester & \(\bullet\) & \(\bullet\) & \(\bullet\) & \(\bullet\) & & & \(\bullet\) & \(\bullet\) & \(\bullet\) \\
4 & 1,3-bis(1,1-dimethylethyl)benzene & aromatic & \(\bullet\) & \(\bullet\) & \(\bullet\) & \(\bullet\) & \(\bullet\) & \(\bullet\) & \(\bullet\) & \(\bullet\) & \(\bullet\) \\
5 & 2,4-heptadiene & aldehyde & \(\bullet\) & \(\bullet\) & \(\bullet\) & & & & & \(\bullet\) & \(\bullet\) \\
6 & 3-ethyl-1,4-hexadiene & diene & \(\bullet\) & \(\bullet\) & \(\bullet\) & & & & & & \(\bullet\) \\  & & carboxylic & & & & & & & & & & \(\bullet\) \\  & acid & & & & & & & & & & & \(\bullet\) \\
8 & 2,6,6-trimethyl-1-cyclohex-1- & & aldehyde & \(\bullet\) & & & & & & & \(\bullet\) & \(\bullet\) \\  & carboxaldehyde & & & & & & & & & & & \\
9 & fumaratic acid 3-methylbut-3-enyl & ester & \(\bullet\) & & & & & & & & \\  & undecyl ester & & & & & & & & & & \\
10 & phenol & phenol & \(\bullet\) & & & & & & & & \\
11 & [(2-methylpropyl)thio]-benzene & aromatic & & & & & & & & & & \\
12 & glycerol 1,2-diacetate & ester & & & & & & & & & \\
13 & 3-furanacetic acid & carboxylic & & & & & & & & & \\  & acid & & & & & & & & & & \\
14 & 4-(1-hydroxyallyl)-2-methoxyphenol & phenol & & & & & & & & & & \\
15 & 5-pentyl-1,3-benzenediol & alcohol & & & & & & & & & \\
16 & fumaratic acid 2-decyl dodecyl ester & & & & & & & & & & \\
17 & dihydromethyljasonate & ester & \(\bullet\) & & & & & & & & \\
18 & 2,4-di-_tert_-butylphenol & phenol & & & & & & & & & \\
19 & 5,6,7,7a-tetrahydro-4,4,7a-trimethyl- & & & & & & & & & & \(\bullet\) & \(\bullet\) & \(\bullet\) \\  & 2(4_H_)-benzofuranone & & & & & & & & & & & \\
20 & mequinol & phenol & & & & & & & & & \\ \hline \hline \end{tabular} \({}^{*}\)Three replicates of each sample were analysed.  
\end{table} 
Table 4: Selected quality markers. Symbol \({}^{\prime\bullet}\)\({}^{\prime\bullet}\) means that compound was present in a sample. hydrogen-donor compounds. The total phenols results agree with the results obtained in the AOX study. It should be mentioned that the presented study also has limitations due to the analytical method applied. The proposed study doesn't detect all possible compounds present in the samples. Complete profile of metabolites should contain also non-volatile compound detected by UPLC methods as non-volatile fraction has its own contribution to AOX. It should be highlighted that such a study has been already performed as the first part of this investigation project [21; 22]. On the other hand, it is also possible that not all the volatile compounds present in the samples were detected. It is due to the selection of specific fiber for SPME and a specific type of chromatographic column. The results may allow in the future the creation of mixtures of extracts of the same plant with different AOX properties that would be applied in the food industry area, for example as dietary supplements, food additives, and active packaging components. Moreover, plants from specific locations can be collected to obtain extracts with targeted compounds with unique properties. For this purpose, the extracts and plants' characterisation is fundamental to guarantee authentication and avoid fraud, which is pretty standard in plants, spices, and herbal extracts. The list of quality markers for the analyzed samples is provided. Conceptualization, M.W., D.P., C.N. and E.A. ; methodology, D.P., M.A.R. and P.V. ; software, D.P. ; validation, M.W., D.P., M.A.R. and P.V; formal analysis, M.W. and P.V. ; investigation, M.W., D.P., M.A.R. and P.V. ; data curation, M.W., D.P., M.A.R. and P.V.