INFORM June 2026

24 INFORM JUNE 2026 , VOL. 37, NO. 6

AMINO ACIDS AND PEPTIDES AS ANTIOXIDANTS Sadia Firdaus and Yonghui Li WHY ANTIOXIDANTS MATTER Oxidative stress is an important factor that disrupts the function of biological systems and food materials. Growing demand for new antioxidant sources is pushing researchers to search new frontiers. Protein fragments called bioactive peptides are one promising, but a commercially less

In some cases, they enhance antioxidant systems on a larger scale, which makes them important as both functional ingredients and building blocks for bioactive peptides. AMINO ACIDS AS ANTIOXIDANT MOLECULES Based on their side chain properties, amino acids can be broadly classified as non-polar, polar uncharged, or charged. The functional groups determine the nature of their interaction with radical species. Depending on the environment, amino acids can give up hydrogen atoms to neutralize free radicals or transfer electrons to terminate oxidative chain reactions. This behavior is dependent on pH, as protonation and ionization states influence whether hydrogen or electron transfer dominates. In real systems, these phenomena lead to several antioxidant routes. Amino acids can also scavenge free radicals, interrupt propagation reactions, or chelate prooxidative metal ions, limiting their catalytic role in lipid oxidation. Enhanced interaction with lipid peroxides

explored group of molecules. The peptides are composed of amino acids that provide the antioxidant power. Their chemical diversity allows them to act as effective antioxidant molecules, particularly in food, feed, and biological systems where oxidation is a key concern. As artificial intelligence and other computational tools become more widespread, these technologies can accelerate bioactive peptide discovery, risk assessment, and practical application in markets valued in the billion dollar range.

It results primarily from a mismatch between the production of reactive oxygen species (ROS) and antioxidant defences. Normally, ROS are produced as side products of metabolism and respiration. When their levels increase beyond control, they start disrupting normal cellular activities. The consequences include oxidative damage such as peroxidation of lipids, modification of proteins, and loss of overall cellular function—one of the reasons for aging and disease. The same principle applies to food systems where oxidative reactions cause a decline in the quality of products, their stability, and shelf life. Antioxidants are in increasingly high demand as food preservatives, as well as nutraceuticals and skincare products. Consumers want naturally sourced antioxidant systems, in particular. Often overlooked in this context, amino acids can contribute to antioxidant activity. They counteract reactive species and participate in redox processes.