Essential Oils as Natural Defenders: Exploring Their Antioxidant and Antimicrobial Potential Against...

This study explores the potential of six essential oils (EOs): clove (Syzygium aromaticum); pennyroyal (Mentha pulegium); jasmine (Jasmin officinal); pin (Pinus sylvestris var. sylvestris L); rosemary (Rosmarinus officinalis); and peppermint (Mentha x piperita), extracted from aromatic and medicinal plants highlighting their bioactive properties. Phytochemical analysis was conducted throughout GC-MS. The antioxidant activity was evaluated by DPPH method, and their antimicrobial potential was tested against three reference bacterial strains and one isolated multidrug-resistant bacterium (S. capitis), using the tests of disc-diffusion, minimum inhibitory, and bactericidal concentrations. The chemical composition identified major compounds including: eugenol 74.5% in S. aromaticum, pulegone 73.07% in M. pulegium, n-hexyl cinnamaldehyde 23.61% in J. officinal, terpinen-4-ol 24.24% in P. sylvestris, eucalyptol 41.82% in R. officinalis, and menthol 44.67%, in M. piperita. In addition, M. pulegium showed the weakest antioxidant potential, whereas S. aromaticum was the most effective EO, as it illustrated the highest antioxidant effect and the strongest antimicrobial activity. In addition, its combination with each tested antibiotic significantly enhanced the antimicrobial activity against S. capitis, highlighting the synergistic potential of these combinations. This study fills a critical gap in the literature, as no prior research has examined these interactions. The statistical analysis revealed distinct groupings among the six EOs based on their chemical composition and biological activities. In this way, strong positive correlations were observed between major compounds, antibacterial, and antioxidant activities. This research highlights the promising use of some EOs as remarkable antioxidant and to combat infections caused by antibiotic-resistant bacteria, indicating their promising therapeutic applications.