Action Mechanism of Essential Oils or Their Components Against Pathogenic Bacteria: Literature Review

Essential oils (EOs), derived from medicinal and aromatic plants, are natural mixtures of volatile, oily compounds with varying compositions and antibacterial mechanisms. Understanding the mechanisms of EOs and their components (EOCs) is essential for predicting their impacts on various microbes and their interactions with antibiotics. This understanding is the key to developing effective strategies to combat and overcome bacterial resistance. This review employs a thematic synthesis of research, first presenting the main chemical structures of EOCs before categorizing their proposed antibacterial mechanisms. The mechanisms of EOs and EOCs include membrane disruption, leading to increased permeability, inhibition of energy production, protein dysfunction, interference with nucleic acids (DNA/RNA), efflux pump inhibition and interference with other cellular processes such as virulence mechanisms (e.g., quorum sensing, biofilm formation and toxin production). A significant advantage is their ability to act synergistically with antibiotics, making them effective not only against antibiotic-sensitive bacteria but also against resistant strains. Through these various mechanisms, EOs present a promising and effective approach to overcoming bacterial infections in an era of increasing antibiotic resistance.