Federal Research Institute of Nutrition and Food, Max Rubner-Institut, Department of Safety and Quality of Fruit and Vegetables, Karlsruhe, Germany.
Am J Clin Nutr. 2013 Feb;97(2):295-309. doi: 10.3945/ajcn.112.049379. Epub 2013 Jan 2.
Strong interindividual differences in the microbial conversion of some dietary polyphenols have been reported. In-depth studies of trans-resveratrol metabolism by human gut microbiota, however, are lacking, and only one bacterial metabolite, namely dihydroresveratrol, has been described.
The aim of this study was to elucidate interindividual differences in trans-resveratrol metabolism by human gut microbiota and to identify bacterial strains involved.
In the first part of the study, in vitro fermentation experiments were performed with feces samples from 7 healthy volunteers, and metabolite formation was measured by liquid chromatography-ultraviolet/visible (UV/Vis)-mass spectrometry (MS)/MS detection. Microbial diversities in 3 feces samples were analyzed by high-throughput pyrosequencing and quantitative real-time polymerase chain reaction. In addition, trans-resveratrol conversion experiments were conducted with selected fecal bacterial strains in pure culture. The second part of the study was a controlled intervention study with 12 healthy volunteers. After a washout period, all of the subjects received a one-time oral dose of 0.5 mg trans-resveratrol/kg body weight in the form of a grapevine-shoot supplement, and 24-h urine samples were analyzed by liquid chromatography-UV/Vis-MS/MS.
Besides dihydroresveratrol, 2 previously unknown bacterial trans-resveratrol metabolites were identified in vitro and in vivo: 3,4'-dihydroxy-trans-stilbene and 3,4'-dihydroxybibenzyl (lunularin). Their formation, however, varied among the volunteers. Two strains, Slackia equolifaciens and Adlercreutzia equolifaciens, were identified as dihydroresveratrol producers. Gut bacteria able to produce dehydroxylated metabolites could, however, not be identified.
trans-Resveratrol metabolism by human gut microbiota shows pronounced interindividual differences, which should be taken into account during investigation of health-related effects of this stilbene. This trial was registered at the German Clinical Trials Register as DRKS00004311, Universal Trial Number (WHO) UTN: U1111-1133-4621.
据报道，某些膳食多酚在微生物转化方面存在很强的个体间差异。然而，人体肠道微生物群对反式白藜芦醇代谢的深入研究还很缺乏，目前仅描述了一种细菌代谢产物，即二氢白藜芦醇。
本研究旨在阐明人体肠道微生物群对反式白藜芦醇代谢的个体间差异，并确定涉及的细菌菌株。
在研究的第一部分，我们对 7 名健康志愿者的粪便样本进行了体外发酵实验，并通过液相色谱-紫外/可见（UV/Vis）-质谱（MS）/MS 检测来测量代谢产物的形成。通过高通量焦磷酸测序和实时定量聚合酶链反应分析了 3 个粪便样本中的微生物多样性。此外，我们还在纯培养中对选定的粪便细菌菌株进行了反式白藜芦醇转化实验。研究的第二部分是一项有 12 名健康志愿者参与的对照干预研究。在洗脱期后，所有受试者一次性口服 0.5 mg/kg 体重的以葡萄藤芽补充剂形式的反式白藜芦醇，并用液相色谱-UV/Vis-MS/MS 分析 24 小时尿液样本。
除了二氢白藜芦醇外，我们还在体内和体外鉴定出了另外 2 种以前未知的细菌反式白藜芦醇代谢物：3,4'-二羟基-反式-二苯乙烯和 3,4'-二羟基联苯（lunularin）。然而，它们的形成在志愿者之间存在差异。2 株细菌，即 Slackia equolifaciens 和 Adlercreutzia equolifaciens，被鉴定为二氢白藜芦醇的产生菌。然而，能够产生去羟基代谢物的肠道细菌尚无法确定。
人体肠道微生物群对反式白藜芦醇的代谢存在明显的个体间差异，在研究这种二苯乙烯对健康相关影响时应考虑到这一点。本试验在德国临床试验注册中心注册，注册号为 DRKS00004311，世界卫生组织（WHO）通用试验编号（UTN）为 U1111-1133-4621。
