GC/MS and PCA Analysis of Volatile Compounds Profile in Various Ilex Species

Species of <i>Ilex</i> genus are particularly rich in bioactive constituents such as polyphenols, saponins, and alkaloids. In terms of phytochemical research, volatile compounds have not been as widely investigated as non-volatile ones. Therefore, in the present research we investigated the phytochemical profile of selected <i>Ilex</i> species by headspace-solid phase-microextraction coupled with gas chromatography-mass spectrometry (HD-SPME-GC/MS). Phytochemical profile between the same and different species was variable. For this reason, it was investigated by principal component analysis (PCA), matrix correlation (calculation of R² and Pearson correlation parameter between samples) as well as hierarchical clustering (dendrogram). In our results, we exhibited that the amount of (<i>Z</i>)-2-hexenal and methyl salicylate was the most important factor for ascertaining similarity between samples. However, concentrations of some of these components were insufficient to describe all dependencies between <i>Ilex</i> specimens. Further analyses (PCA and dendrogram), exhibited that thymoquinone had secondary impact on phytochemical profiles similarity, as did <i>o</i>-methyl-anisole, (<i>E</i>)-2-decenal, salicylaldehyde and (<i>Z</i>)-3-hexen-1-ol. Differences of profile between samples may result from many factors such as local environmental conditions, creation of different chemotypes or even infestation by unknown pathogens or the presence of non-pathogenic microorganisms. Further research is required to investigate this phenomenon. Moreover, it was found that some of <i>Ilex</i> species may be potential sources of bioactive volatile components.