## 4 Conclusions  
In conclusion, the results obtained show that essential oils have antioxidant activity, important in the treatment of various inflammatory diseases. The antioxidant activity and composition of essential oils are closely related to the environmental conditions and the geographical origin of the plants from which the essential oils were obtained. The compounds that ensure the antioxidant activity of the investigated essential oils are car-vacrol, 1,8-cineole, y-terpinene, linalool, \(\beta\)-caryophyllene, terpinolene, \(\alpha\)-phellandrene, and ane-thole. GC-MS analyses revealed that all essential oils are mainly characterized by the presence of monoterpene hydrocarbons and oxygenated monoterpenes, except in the case of fennel essential oil which contains phenylpropanoids as its main components (compounds that can be classified as phenylpropenes or allylbenzenes). This study tested  
Figure 11: Graphical representation of the MCBE values for yeast strain _Candidida albicans_ ATCC 10231; FEN (fennel EO); SV (sage EO); EUC (eucalyptus EO); CI (thymme EO); PIN (pine EO).  
Figure 10: Graphical representation of the MCBE values for Gram-negative strain _Escherichia coli_ ATCC 25922; FEN (fennel EO); SV (sage EO); EUC (eucalyptus EO); CI (thymme EO); PIN (pine EO).  
the antimicrobial activity of five essential oils on the growth, multiplication, and biofilm formation of standard microbial strains: _Staphylococcus aureus_ ATCC 2592, _Pseudomonas aeruginosa_ ATCC 27853, _Escherichia coli_ ATCC 25922, _Candida albicans_ ATCC 10231. Both qualitative and quantitative test results show an increased sensitivity of _Escherichia coli_ ATCC 25922 strains to all tested essential oils. The qualitative results show the largest diameters of the inhibition zones for thyme EO, followed by sage and fennel EO. Thyme EO was also the only essential oil that expressed an inhibitory effect on _Candida albicans_ ATCC 10231 yeast strain. The quantitative results highlighted the lowest inhibitory concentration for sage EO (0.156%) and thyme EO (0.626%). On the opposite, the highest values of the minimum inhibitor concentration were observed for pine EO (10%). The MCBE value was close to the MIC value for most of the tested essential oils.  
Conceptualization, D.G., A.A. and I.A.; Methodology, A.R., L.A., L.M.D., A.-D.R. and E.G.; Software, A.R., A.A. and A.S.; Validation, A.A., I.A., L.M.D., A.-D.R., J.T. and E.G.; Investigation, D.G., A.R., A.A., L.M.D., J.T. and A.S.; Resources, A.R., A.A. and E.G.; Data curation, D.G. and A.R.; Writing--original draft preparation, D.G., A.R., A.A. and I.A.; writing--review and editing, D.G. and A.R. All authors have read and agreed to the published version of the manuscript.  
This work was supported by a grant from the Romanian Ministry of Education and Research, CCCDI-UEFISCDI, Project number PN-III-P2-2.1.-PED-2019-5236, within PNCDI III. In addition, financial support from the Competitiveness Operational Program 2014-2020, Action 1.1.3: Creating synergies with RDI actions of the EU's HORIZON 2020 framework program and other international RDI programs, MySMIS Code 108792, Acronym project \"UPB4H\", financed by contract 250/11.05.2020 is gratefully acknowledged.  
Not applicable.  
The experimental data on the results reported in this manuscript are available upon on official request to the corresponding authors.  
The authors declare no conflict of interest.