Tan N H, Tan C S
Department of Biochemistry, University of Malaya, Kuala Lumpur.
Anal Biochem. 1988 May 1;170(2):282-8. doi: 10.1016/0003-2697(88)90632-x.
A convenient acidimetric assay for phospholipase A using egg yolk suspension as substrate has been developed. The substrate mixture consists of 1 part egg yolk, 1 part 8.1 mM sodium deoxycholate, and 1 part 18 mM calcium chloride. Phospholipase A activity is measured by following the initial rate of pH change, which is linear between pH 8.0 and 7.75 and is proportional to enzyme concentration over a wide range. The assay is highly reproducible, with a coefficient of variation of 3%, and as sensitive as most established assays for phospholipase A. The assay uses inexpensive and easily available substrate and is simple to perform. It is particularly useful for monitoring phospholipase A activity in chromatography fractions.
已开发出一种便捷的酸量滴定法，该方法以蛋黄悬液为底物来测定磷脂酶A。底物混合物由1份蛋黄、1份8.1 mM脱氧胆酸钠和1份18 mM氯化钙组成。通过跟踪pH值变化的初始速率来测定磷脂酶A的活性，该变化在pH 8.0至7.75之间呈线性，并且在很宽的范围内与酶浓度成正比。该测定法具有高度可重复性，变异系数为3%，并且与大多数已确立的磷脂酶A测定法一样灵敏。该测定法使用廉价且易于获得的底物，操作简单。它对于监测色谱馏分中的磷脂酶A活性特别有用。
