Antioxidant definition in biochemistry
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Antioxidant Definition in Biochemistry
Biochemical Definition and Function of Antioxidants
In biochemistry, an antioxidant is a substance that can delay, prevent, or inhibit the oxidation of other molecules, especially by neutralizing reactive oxygen species (ROS) and free radicals that can cause cellular damage 123569. Antioxidants act as a defense system, protecting cells and tissues from oxidative stress, which is an imbalance between the production of harmful oxidants and the body’s ability to counteract their effects 156.
Mechanisms of Antioxidant Action
Antioxidants work through several chemical mechanisms, including hydrogen atom transfer (HAT), single electron transfer (SET), and chelation of transition metals 238. These mechanisms allow antioxidants to neutralize free radicals or reactive species, thereby preventing chain reactions that can damage lipids, proteins, and DNA 2368. The specific mechanism depends on the chemical structure of the antioxidant molecule 28.
Types and Sources of Antioxidants
Antioxidants can be classified as either enzymatic (produced by the body, such as superoxide dismutase, catalase, and glutathione peroxidase) or non-enzymatic (obtained from the diet, such as vitamins C and E, carotenoids, flavonoids, and other plant-derived compounds) 15679. Endogenous antioxidants are synthesized within the body, while exogenous antioxidants are obtained from food or supplements 569.
Biological Importance and Health Implications
Antioxidants are essential for maintaining cellular homeostasis and protecting against diseases linked to oxidative stress, such as neurodegenerative disorders, cardiovascular diseases, cancer, diabetes, and aging-related conditions 13569. They are also used as preservatives in food and pharmaceutical products to prevent oxidation and spoilage 37.
Conclusion
In summary, antioxidants in biochemistry are substances—either naturally occurring or synthetic—that protect biological systems by neutralizing harmful oxidants and preventing oxidative damage. Their action is crucial for cellular health, disease prevention, and the stability of food and pharmaceutical products 12356789.
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