Significance of Measurement: Malondialdehyde (MDA) is a major end product of lipid peroxidation. Its concentration reflects the extent of membrane lipid oxidative damage and is commonly used as a biomarker of oxidative stress. Principle of Measurement: MDA reacts with thiobarbituric acid (TBA) to form a red-colored MDA–TBA adduct with a characteristic absorbance at 532 nm. MDA content is calculated based on absorbance at this wavelength.