## 3 Discussion
As a result, cells exhibit limited activity of \(\beta\)-1,3-glucan synthase as well as chitin synthase. Sorbitol is therefore a factor that causes slight cell stress, which may cause the inhibition of cell growth in the presence of some nonspecific cell wall inhibitors [30; 31]. As both cinnamaldehyde and sorbitol influence \(\beta\)-1,3-glucan synthase as well as chitin synthase activity, the decrease in MIC value for cinnamon oil in the presence of this osmoprotectant is explainable. In the case of the remaining oils, the effect on the cell wall was not so evident. A two-fold increase of the MIC value in the presence of sorbitol in the medium was observed for basil oil (for both _C. albicans_ and _C. glabrata_). The investigations of basil oil's mode of anticandidal action are not very abundant, so it is hard to find a correlation concerning its effect on the cell wall. According to [PERSON]'s group basil oil, as well as geraniol, contributes to marked cell wall thickening (results obtained on the basis of transmission electron microscopy images) [32]. On the other hand, [PERSON] et al. reported that _O. basilicum_ extracts possess antibacterial activity by causing bacterial cell wall degradation [33]. The effect of _P. gravevelens_ EO is also not obvious. [PERSON] and coworkers noted a two-fold increase of MIC of this EO in a medium supplemented with sorbitol, thereby suggesting its influence on the cell wall [7]. In our research, an increase in MIC value was not observed for _C. albicans_ isolate but a two-fold increase was noted for _C. glabrata_; this does not give us an unambiguous answer about the influence of the oil on the cell wall. Overall, the changes in minimum inhibitory concentrations for the tested EOs were not significant in comparison to other well-known cell wall inhibitors; thus, we claim that the cell wall is a target of secondary importance. Further research revealed that thyme, lemon, and clove oils influence the cell membranes. Up to a 16-fold increase in MIC value was observed for lemon oil for the _C. glabrata_ strain, even higher than for amphotericin B (8-fold increase for both species), which binds the ergosterol found in lipid bilayer membranes. In the case of _C. albicans_, the change was not so noticeable and reached a 2-fold increase. Additionally, we suggest that the _C. glabrata_ cell membrane may be more susceptible to the action of some EOs, as can be seen (apart from the mentioned lemon EO) in the case of geranium and clove oil (8- and at least 4-fold increase, respectively, while for _C. albicans_ no increase was observed for geranium oil and for clove oil there was at least a 2-fold increase). The 4-fold increase of thyme oil MIC values in both tested strains also indicates its significant role in cell membrane disintegration. On the other hand, cinnamon oil does not seem to affect the cell membrane, as MIC values for this EO in the presence or absence of ergoesterol were unchanged for both species. Results obtained by other researchers also indicate the cell membrane as a potential molecular target of some EOs or their components. This can be, for instance, confirmed by [PERSON] and co-workers, who suggested that limonene inhibits _C. albicans_ growth by cell wall/membrane damage [34]. A similar statement was made by [PERSON] et al. pertaining to clove oil [35]. The influence of thyme oil on the cell membrane was observed by [PERSON] and co-workers, who noticed an up to 32-fold increase of MIC for this oil in ergosterol assay toward _C. albicans_ ATCC 10231 [36]. We also evaluated cell membrane disintegration by the measurement of potassium ion leakage. In the case of clove, the leakage was dose-dependent. The highest efflux was noticed in the case of thyme oil, but it was not proportional to the concentration used (probably the concentration of 1 \(\times\) MIC was large enough to cause the highest outflow of ions, so a further increase did not result in additional changes).