RESUMO
Objective To develop an efficient method for the determination of activity of human lymphocyte kynureninase by high performance liquid chromatography. Methods Protein containing kynureninase was extracted from lymphocytes.The reaction was made with 3-hydroxyanthranilic acid as substrate and pyridoxal-5'-phosphate as coenzyme.The product was determined by high performance liquid chromatography and fluorescence detection.(Results)Standard curve of 3-hydroxyanthranilic acid was highly linear over the range from 2 to 400 nmol/L.The intra-day coefficient of variation(CV) was less than 3.0% and the inter-day CV was less than 3.2%. Conclusion(The developed) assay is efficient and can be used to determine the activity of kynureninase from kinds of tissues.