谷氨酸脱氢酶法测定螺旋藻蛋白质

MEASURING SPIRULINA PROTEIN BY GLUTAMATE DEHYDROGENASE

建立一种用谷氨酸脱氢酶测定螺旋藻蛋白质的方法。将螺旋藻蛋白质消化成（ＮＨ_４）_２ＳＯ_４，再用谷氨酸脱氢酶动力法在自动生化分析仪上测定（ＮＨ_４）_２ＳＯ_４浓度，计算螺旋藻蛋白质含量。该法线性范围为０～９．０ｍｍｏｌ／Ｌ；变异系数０．５１％～１．９６％；回收率９６．６％～１０３．０％；准确性与蒸馏法无差异，Ｐ＞０．０５；与蒸馏法相关性，ｒ＝０．９９９９。本酶法准确度高，重复性好，测定范围宽，抗干扰能力强，与蒸馏法相关性好，酶试剂稳定、用量少、价廉，且简便快速，宜批量测定。

This article is to establish a method for measuring spirulina protein by glutamate dehydrogenase. The spirulina protein was completely degraded to the (NH_4)_2SO_4 according to the Kjeldahel procedure. Then,the concentration of (NH_4)_2SO_4 in the digest juice was measured by glutamate dehydrogenase with automatic analyzer,and the spirulina protein concentration was calculated. The Linearity of test was up to 9.0mmol/L. The withinrun coefficients of variation were 0. 51％ to 1.96％. The recoveries ranged from 96. 6％ to 103.0％. Comparing this method with the distillation of the Kjeldahel method,we found that the accuracy was not significantly different (P>0. 05),and the coefficient of relativity was 0. 9999. This method is simple,sensitive and accurate. This procedure has the advantage of eliminating the distillation and titration steps of the Kjeldahel method and it is ideal for spirulina protein assays,since many samples can be run in a single day.