L-Methionine sulfoxide is primarily used in biochemical research to study oxidative stress and protein damage. It serves as a marker for oxidative damage in proteins, helping researchers understand the effects of reactive oxygen species (ROS) on cellular components. This compound is also utilized in the development of therapeutic strategies aimed at mitigating oxidative stress-related diseases, such as neurodegenerative disorders and cardiovascular conditions. Additionally, L-Methionine sulfoxide is explored in the field of enzymology to investigate the activity of methionine sulfoxide reductases, enzymes that play a crucial role in repairing oxidized methionine residues in proteins. Its applications extend to the study of aging processes and the development of antioxidants designed to protect cells from oxidative damage.