Essential Oils as Nature’s Dual Powerhouses for Agroindustry and Medicine: Volatile Composition and Bioactivities—Antioxidant, Antimicrobial, and Cytotoxic

Abstract

Essential oils (EOs), which are complex mixtures of plant-derived volatile compounds, have been utilized for centuries in the medical, food, and pharmaceutical industries because of their diverse biological properties. In recent years, there has been growing interest in elucidating the bioactivities of essential oils and their underlying mechanisms of action. This study aimed to investigate the antioxidant, antimicrobial, and cytotoxic characteristics of Laurus nobilis, Eucalyptus camaldulensis, Rosmarinus officinalis, and Mentha suaveolens oils and relate them to their volatile compound content. The volatile compounds of the essential oils were characterized and quantified by gas chromatography, the antioxidant activity was quantified using the ABTS assay, the antibacterial activity was quantified using broth microdilution and agar diffusion techniques, and the MTT assay was used to establish the cytotoxic potential. This study revealed a significant antioxidant capacity, which correlated with the proportion of terpenes known for their antioxidant properties. The antioxidant potency was ranked in descending order: R. officinalis, M. suaveolens, E. camaldulensis, and L. nobilis. Antimicrobial testing demonstrated that all the examined essential oils were effective against the evaluated microbial species, including both Gram-positive (Listeria innocua) and Gram-negative (Escherichia coli) bacteria. Additionally, all the tested essential oils triggered cell death in the human epithelioid cervical carcinoma (HeLa) cell line. Collectively, this article highlights the promising therapeutic and alimentary potential of essential oils and underscores the need for further research to fully harness their benefits in industrial settings.