Since ancient times, medicinal plants have been used around the world to treat a wide range of ailments, diseases, and wounds. They are part of the socio-cultural legacy of different countries, evidenced by the ethnobotanical information showed in their pharmacopeias. Medicinal plants are a rich source of phytochemicals and natural compounds such as alkaloids, terpenes, glucosinolates, phenolic compounds, and flavonoids. Plant-derived products and their corresponding metabolites have garnered considerable interest at the clinical, pharmacological, cosmetic and even industrial levels. Indeed, natural products are extremely rich sources of biomolecules useful for a multitude of applications.

Nonetheless, regarding the pharmacological approach, it is of utmost importance to highlight that natural products are not drugs, but instead are a pool of phytochemicals for drug development. In the past few decades, a wide variety of methods/techniques have been used to assess the renowned historical significance of natural products, also emphasizing their potential as a source of novel compounds that can be directly applied as therapeutic agents, and even as a source of inspiration for medicinal chemists generating new synthetic organic compounds. On the other hand, regarding the high demand by consumers for healthy products, a wide variety of plant-derived foodstuffs have also been introduced into worldwide markets, contributing to shelf-life extension, the maintenance and even improvement of organoleptic and nutritional attributes, the formulation of functional products, among other biotechnological approaches. In this context, and considering that most secondary metabolites are produced for the protection of the own plant, some of the bioactive constituents have also been increasingly screened for crop protection, including biocide formulations.

Thus, considering the high interest in plant-derived secondary metabolites as an emerging challenge for modern drug development, crop protection and biotechnological processes, this Special Issue will cover a wide variety of areas. This Special Issue calls for original research and review articles regarding the phytochemical, ethnopharmacological, and bioavailability research of medicinal plants used around the world.

Potential topics include but are not limited to the following:

• The role of natural products in the maintenance of human health
• Ethnomedicinal use and phytohchemistry of medicinal plants
• Bioactive potential of food components
• Identification and characterization of phytochemicals from medicinal plants used around the world
• Mechanism of action of bioactive compounds
• Chemical structure-biological activity relationship
• Bioaccessibility studies of phytochemicals from medicinal plants used around the world
• Bioactive properties of phytochemicals from medicinal plants against noncommunicable diseases
• Bioactive properties of phytochemicals from medicinal plants against infectious diseases