Essential Oils: An Impending Substitute of Synthetic Antimicrobial Agents to Overcome Antimicrobial Resistance

Antimicrobial resistance (AMR) is an emerging problem in the world that has a significant impact on our society. AMR made conventional drugs futile against microorganisms and diseases untreatable. Plant-derived medicines are considered to be safe alternatives as compared to synthetic drugs. Active ingredients and the mixtures of these natural medicines have been used for centuries, due to their easy availability, low cost, and negligible side effects. Essential oils (EOs) are the secondary metabolites that are produced by aromatic plants to protect them from microorganisms. However, these EOs and their constituents have shown good fighting potential against drug-resistant pathogens. These oils have been proved extremely effective antimicrobial agents in comparison to antibiotics. Also, the combination of synthetic drugs with EOs or their components improve their efficacy. So, EOs can be established as an alternative to synthetic antimicrobial agents to eradicate tough form of infectious microorganisms. EO’s can interact with multiple target sites, like the destruction of cytoplasm membrane or inhibition of protein synthesis and efflux pump, etc. The purpose of this review is to provide information about the antimicrobial activity of EOs attained from different plants, their combination with synthetic antimicrobials. In addition, mechanism of antimicrobial activity of several EOs and their constituents was reported.