From Chemotaxonomy to Green Biocides: An Overview of New Studies on the Composition and Functional Properties of Some Plant Essential Oils

In recent years, the search for sustainable, bio-based alternatives to synthetic chemicals has intensified, positioning plant essential oils (EOs) at the forefront of applied phytochemical research. The following collection of ten articles from different geographical regions, published in Plants as part of the Special Issue “Plant Essential Oil with Biological Activity: 3rd Edition,” covers various aspects of recent scientific research on plant EOs, ranging from chemotaxonomy to green biocides, with particular emphasis on chemical composition and functional properties. Further attention is given to specific predominant single constituents and their bio-selectivity, modes of action, and innovative applications in the medical and pharmaceutical sectors, particularly against major diseases such as cancer and Alzheimer’s.