Sulfonation is an important high affinity elimination pathway for phenolic compounds.

In this study sulfonation of 7-hydroxycoumarin and 13 its derivatives were evaluated in liver cytosols of human and six animal species. 7-hydroxycoumarin and its derivatives are strongly fluorescent, and their sulfate conjugates are nonfluorescent at excitation 405 nm and emission 460 nm. A convenient fluorescence based kinetic assay of sulfonation was established.

The sulfonation rate of most of the 7-hydroxycoumarin derivatives was low in liver cytosol of human and pig, whereas it was high with most compounds in dog and intermediate in rat, mouse, rabbit, and sheep. Sulfonation of the 7-hydroxycoumarin derivatives followed Michaelis-Menten kinetics with K_m values of 0.1–12 µM, V_max of 0.005–1.7 µmol/(min * g protein) and intrinsic clearance (V_max/K_m) of 0.004–1.9 L/(min * g cytosolic protein).

Fluorescence based measurement of sulfonation of 7-hydroxycoumarin derivatives provides a sensitive and convenient high-throughput assay to determine sulfonation rate in different species and tissues and can be applied to evaluate sulfonation kinetics and inhibition.

磺化是酚类化合物重要的高亲和力消除途径。

在这项研究中，在人和六种动物的肝细胞质中评估了 7-羟基香豆素及其 13 种衍生物的磺化作用。7-羟基香豆素及其衍生物具有强荧光，它们的硫酸盐偶联物在 405 nm 激发波长和 460 nm 发射波长下无荧光。建立了一种方便的基于荧光的磺化动力学分析。

大多数7-羟基香豆素衍生物在人和猪的肝细胞溶质中磺化率低，而在狗和大鼠、小鼠、兔和羊的中间体中磺化率高。7-羟基香豆素衍生物的磺化遵循 Michaelis-Menten 动力学，K _m值为 0.1–12 µM，V _max为 0.005–1.7 µmol/(min * g 蛋白质)，内在清除率 ( V _max / K _m ) 为 0.004–1.9 L/(min * g 胞质蛋白)。

基于荧光的 7-羟基香豆素衍生物磺化测量提供了一种灵敏且方便的高通量测定方法来确定不同物种和组织中的磺化速率，可用于评估磺化动力学和抑制作用。