The past decade (2015–2025) has seen natural antioxidant research, particularly on artemisinin, phenolic acids, and flavonoids, progress from simple free radical scavenging assays to sophisticated molecular pathway studies, nanotechnology-based delivery, and early-stage clinical trials. These phytochemicals derived from plant genera of diverse origin show multifaceted biological activities such as redox regulation, anti-inflammatory, and chemopreventive effects through major regulatory pathways such as Nrf2/Keap1, NF-κB, and MAPKs. Artemisinin, besides its established antimalarial activity, also emerges as a potent oxidative stress modulator by covalent modification of KEAP1 cysteine residues, activation of NRF2, and induction of cytoprotective genes. Phenolic acids and flavonoids introduce supplementary antioxidant and therapeutic options with evidence for synergistic interactions. Whatever bioavailability and stability problems may exist aside, advances in plant biotechnology, metabolic engineering, and nanoformulations have enhanced yield, potency, and delivery. This review synopsizes a decade of biochemical, pharmacological, and translational advances, highlights gaps in clinical validation, and indicates avenues for the future involving omics technologies and AI-aided metabolic modeling to enable the rational design of next-generation antioxidant therapies.

Secondary metabolites isolated from medicinal plants are of immense therapeutic, nutraceutical, and market importance. Unfortunately, natural biosynthesis of these compounds is generally low, dependent on factors that include the environment and physiology. Over the past few years, biotechnological innovation has opened up new and sustainable approaches to meet the requirement for secondary metabolite production in vitro. This review identifies recent biotechnological interventions such as plant tissue culture, elicitation, metabolic engineering, and synthetic biology that have been successfully utilized to enhance the biosynthesis of bioactive phytochemicals. An emphasis is given to the mechanisms, benefits, and disadvantages of these strategies, with specific reference to prominent medicinal plant species. Future directions are to interface omics tools with AI-powered metabolic pathway modeling for targeted metabolite improvement.