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@article{207114,
        author = {Vaishnavi Chandrakant Labade and Dattatraya Vitthal Kature and Rajendra N. Patil},
        title = {Oxidative Stress, Free Radicals, Antioxidants: A Critical Review with Emphasis on Plant-Derived Antioxidants},
        journal = {International Journal of Innovative Research in Technology},
        year = {2026},
        volume = {13},
        number = {2},
        pages = {3986-4014},
        issn = {2349-6002},
        url = {https://ijirt.org/article?manuscript=207114},
        abstract = {Oxidative stress occurs when the body's production of free radicals and reactive oxygen species (ROS) exceeds its antioxidant capacity, causing progressive damage to lipids, proteins, and DNA. This imbalance is now recognised as a central driver of major chronic diseases including cardiovascular disease, diabetes, cancer, Alzheimer's disease, chronic kidney disease, and accelerated ageing. Synthetic antioxidants such as BHA, BHT, and TBHQ carry serious limitations - carcinogenic potential, prooxidant behaviour, allergenicity, and consistent failure in large-scale clinical trials (SELECT, HOPE, CARET, ATBC) - directing scientific attention toward safer, plant-derived alternatives.
This review comprehensively analyses free radical biology, oxidative stress mechanisms, endogenous antioxidant defences (including the Nrf2 master regulator), and the pharmacology of polyphenols, flavonoids, tannins, terpenoids, and carotenoids. The documented toxicological limitations of synthetic antioxidants and the scientific superiority of multi-mechanism plant antioxidants are critically evaluated.
Systematic evaluation of sixty botanically diverse medicinal and food plant species using DPPH, ABTS, FRAP, CUPRAC, ORAC, and metal chelation assays consistently demonstrated strong to very strong antioxidant activity. Traditional Indian medicinal plants - Curcuma longa, Phyllanthus emblica, Ocimum sanctum, and Moringa oleifera - alongside global species including Punica granatum peel, Syzygium aromaticum, and Rubus occidentalis showed potency equal to or exceeding synthetic antioxidant standards. Plant antioxidants are superior due to multi-mechanism action, Nrf2 activation, pleiotropic bioactivities, and an excellent safety profile, making them the rational choice for antioxidant-based disease prevention and pharmaceutical development.},
        keywords = {Oxidative stress; free radicals; reactive oxygen species; plant-derived antioxidants; polyphenols; flavonoids; Nrf2; DPPH; FRAP; synthetic antioxidants; lipid peroxidation; chronic disease; nutraceuticals},
        month = {July},
        }