Used to measure BCAA (branched-chain amino acid) degradation activity in human biological samples, particularly in research related to metabolic disorders, mitochondrial function, and amino acid metabolism. Helps assess enzyme activity involved in breaking down leucine, isoleucine, and valine. Commonly applied in studies of insulin resistance, obesity, type 2 diabetes, and inborn errors of metabolism. Enables quantitative analysis of metabolic flux in cell cultures, tissue extracts, and serum samples. Supports biomarker discovery and evaluation of therapeutic interventions targeting amino acid metabolism pathways.