Antioxidant activity is the ability of compounds to inhibit, delay, or prevent the oxidation of substrates by scavenging free radicals and neutralizing reactive oxygen species (ROS), thereby protecting cells from oxidative stress and damage. It works by donating electrons or hydrogen atoms to stabilize free radicals, reducing cellular damage, and slowing aging. Mechanisms: These include scavenging free radicals, inhibiting the formation of ROS, repairing oxidative damage, and breaking radical chain reactions. Types: Antioxidants can be enzymatic (e.g., superoxide dismutase, catalase, glutathione peroxides) or non-enzymatic (e.g., vitamin C, vitamin E, polyphones, flavonoids). Sources: Natural antioxidants are found in fruits, vegetables, spices, and herbs. Common sources include berries (anthocyanins), citrus fruits (Vitamin C), nuts/seeds (Vitamin E), and green tea. Measurement: Activity is often measured through assays such as DPPH, H2O2 scavenging, and Total Antioxidant Capacity (TAC). Significance: These activities are crucial for preventing chronic diseases linked to oxidative stress.
Dr. Mallikarjun Kote* (Thu,) studied this question.