I. U. CINQUIMA, Analytical Chemistry Group (TESEA), Faculty of Sciences, University of Valladolid, Valladolid 47011, Spain.
CEBAS-CSIC, Research Group on Quality, Safety, and Bioactivity of Plant-Derived Foods, P.O. Box 164, Espinardo, Murcia 30100, Spain.
J Agric Food Chem. 2023 Feb 15;71(6):3033-3039. doi: 10.1021/acs.jafc.2c07145. Epub 2023 Jan 31.
Urolithins are gut microbiota metabolites produced in humans after consuming foods containing ellagitannins and ellagic acid. Three urolithin metabotypes have been reported for different individuals depending on the final urolithins produced. After absorption, they are conjugated with glucuronic acid (phase II metabolism), and these are the main circulating metabolites in plasma and reach different tissues. Different regioisomeric isomers of urolithin glucuronides have been described. Still, their identification and quantification in humans have not been properly reported due to resolution limitations in their analysis by reversed-phase high-performance liquid chromatography. In the present study, we report a novel method for separating these isomers using supercritical fluid chromatography. With this method, urolithin A 3- and 8-glucuronide, isourolithin A 3- and 9- glucuronide, and urolithin B 3-glucuronide (8-hydroxy urolithin 3-glucuronide; 3-hydroxy urolithin 8-glucuronide; 3-hydroxyurolithin 9-glucuronide; 9-hydroxyurolithin 3-glucuronide; and urolithin 3-glucuronide) were separated in less than 15 min. The proposed method was applied to successfully analyze these metabolites in urine samples from different volunteers belonging to different metabotypes.
尿石素是人类食用含有鞣花单宁和鞣花酸的食物后产生的肠道微生物代谢物。根据最终产生的尿石素，不同个体报告了三种尿石素代谢类型。吸收后，它们与葡萄糖醛酸结合（二期代谢），这些是血浆中主要的循环代谢物，并到达不同的组织。已经描述了尿石素葡萄糖醛酸的不同区域异构体。然而，由于反相高效液相色谱分析的分辨率限制，其在人体中的鉴定和定量尚未得到妥善报道。在本研究中，我们报告了一种使用超临界流体色谱分离这些异构体的新方法。使用该方法，尿石素 A 3-和 8-葡萄糖醛酸、异尿石素 A 3-和 9-葡萄糖醛酸以及尿石素 B 3-葡萄糖醛酸（8-羟基尿石素 3-葡萄糖醛酸；3-羟基尿石素 8-葡萄糖醛酸；3-羟基尿石素 9-葡萄糖醛酸；9-羟基尿石素 3-葡萄糖醛酸；和尿石素 3-葡萄糖醛酸）在不到 15 分钟内得到分离。所提出的方法成功地应用于分析来自不同代谢类型的不同志愿者的尿液样本中的这些代谢物。
