酶偶联分光光度法测定胞内黄嘌呤氧化酶活性

建立了新的酶反应体系显色分光光度法检测节杆菌胞内黄嘌吟氧化酶的活性。考察了温度、pH值和底物浓度对检测体系的影响，确定了黄嘌呤氧化酶活性检测的最优条件，获得了良好的检测线性关系。此检测方法操作简便，结果准确可靠，可作为普通实验室和临床上测定黄嘌呤氧化酶活性的有效生化手段。

Spectrophotometric Assay of Xanthine Oxidase Activity in Cell Extracts Applying Horseradish Peroxidase

A sensitive method to quantify the activity of xanthine oxidase(XOD) in microbial cell extracts through the chromogenic reaction of 4-aminoantipyrine (AAP), phenic acid (PA) and hydrogen peroxide(H2O2), which was produced via the oxidation of xanthine catalyzed by XOD under the help of horseradish per-oxidase(HRP), was developed and applied to Arthrobacter sp. XL in this paper. The influences of temperature,pH value and amount of substrate on the activity of XOD were investigated. The optimal conditions to deter-mine the activity of XOD were obtained as follows:7000 U·L-1 horseradish peroxidase,l mmol·L-1 4-aminoantipyrine,6 mmol·L-1 phenic acid and l mmol·L-1 xanthine were dissolved in 100mmol·L-1 Tris-HCl buffer solution (pH value 8.4), the reaction temperature was 37℃, the reaction time was 20 rain, the detectivewavelength was 508 nm. Under the conditions mentioned above, the linear range of calibration curve was be-be a potential alternative method to determine the activity of xanthine oxidase in areas such as in laboratory orclinical diagnosis.