一种测定柚苷酶鼠李糖苷酶活性的方法。

A method for assaying the rhamnosidase activity of naringinase.

作者信息

Romero C, Manjón A, Bastida J, Iborra J L

出版信息

Anal Biochem. 1985 Sep;149(2):566-71. doi: 10.1016/0003-2697(85)90614-1.

Abstract

The use of the p-nitrophenyl-alpha-L-rhamnopyranoside for the specific measurement of the alpha-rhamnosidase activity of naringinase, by colorimetrically following the appearance of p-nitrophenolate anion, is proposed. Use of this synthetic substrate did not change the pH, temperature, or ionic strength optima of the enzyme. It did, however, result in (a) a decrease of the Michaelis constant of the enzyme, allowing the Vmax to be measured, this being impossible to accomplish with naringin, (b) an increase in the sensitivity of the assay to the presence of inhibitors in the reaction media, (c) an increase in the sensitivity which enabled measurement of low levels of naringinase due to the high absorptivity of p-nitrophenolate, and (d) a quick and cheap method of evaluating the alpha-rhamnosidase activity of naringinase.

摘要

有人提出通过比色法跟踪对硝基酚阴离子的出现，使用对硝基苯基-α-L-鼠李糖苷来特异性测定柚苷酶的α-鼠李糖苷酶活性。使用这种合成底物不会改变酶的最适pH、温度或离子强度。然而，它确实导致了：（a）酶的米氏常数降低，从而能够测量Vmax，而使用柚苷则无法做到这一点；（b）测定对反应介质中抑制剂存在的敏感性增加；（c）由于对硝基酚的高吸光率，灵敏度提高，能够测量低水平的柚苷酶；（d）一种快速且廉价的评估柚苷酶α-鼠李糖苷酶活性的方法。