Essential Oils and their Antimicrobial Activity: A Review

Abstract

Essential oils (EOs) have been used in ethno-medicine as effective and safe antimicrobial agents for a long time. They have been evaluated for the bactericidal, fungicidal, antiparasitical, insecticidal, virucidal, medicinal, and cosmetics applications. EOs are derived from various species of edible and medicinal plants, including herbs and spices. They are liquid and volatile complex mixtures of compounds obtained from different parts of plants such as tea tree, oregano tree, clove, thyme, citrus, and mint. Terpenes and terpenoids and their derivatives are the major constituents of EOs, while aromatic and aliphatic components are the minor constituents. EOs possess strong antibacterial and antifungal properties for both susceptible and resistant strains, where they have the ability to damage the structural integrity of the cell membrane, induce leakage of cell constituents, influence the cell metabolism, and eventually cause cell death.