酶催化分光光度法测定L-酪氨酸

利用L-酪氨酸对酶催化体系的抑制作用,建立了一种操作简便、灵敏的分析L-酪氨酸的新方法。优化了该抑制体系的实验条件,L-酪氨酸5.0×10-7mol/L~1.0×10-4mol/L浓度范围内与抑制率有较好的线性关系,检出限为2.6×10-7mol/L。将浓度为2.0×10-5mol/L的L-酪氨酸进行11次平行测定,其RSD为2.1%。该法已成功的应用于啤酒、葡萄酒中L-酪氨酸含量的测定。

Determination of L-tyrosine by enzyme catalytic spectrophotometry

A simple and sensitive spectrophotometric method for the determination of L-tyrosine was developed based on the inhibition of L-tyrosine on enzyme catalysis system. The optimal experimental conditions are studied. The concenlration of L-tyrosine showed a good linear relationship with percentage inhibition of enzyme catalysis system when ranged between 5.0 x 10-Tmol/L-1.0 10-4mol/L. The detection limit of L-tyrosine was 2.6 × 10^-7mol/L. The relative standard deviation of 11 parallel determinations was 2.1% for 2.0× 10^-4mol/L L-tyrosine. This method was successfully applied to determine L-tyrosine in beer and grape wine.