Shehata Emad, Day-Walsh Priscilla, Kellingray Lee, Narbad Arjan, Kroon Paul A
Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK.
Chemistry of Flavour and Aroma Department, National Research Centre, 33 El Buhouth St., Dokki, Cairo, 12622, Egypt.
Mol Nutr Food Res. 2023 Oct;67(19):e2300036. doi: 10.1002/mnfr.202300036. Epub 2023 Jul 31.
The consumption of dietary anthocyanins is associated with various health benefits. However, anthocyanins are poorly bioavailable, and most ingested anthocyanins will enter the colon where they are degraded to small phenolic metabolites that are the main absorbed forms. Little is known about the processes of anthocyanin degradation in the gut and the role of the human gut microbiota. This study aims to determine the contribution of spontaneous and microbiota-dependent degradation of anthocyanins in the human colon.
Purified anthocyanin extracts from black rice and bilberry were incubated in an in vitro human fecal-inoculated pH-controlled colon model over 24 h and anthocyanins were analyzed using HPLC-DAD. The study shows that the loss of anthocyanins occurs both spontaneously and as a consequence of metabolism by the gut microbiota. The study observes that there is high variability in spontaneous degradation but only modest variation in total degradation, which included the microbiota-dependent component. The degradation rate of anthocyanins is also shown to be dependent on the B-ring substitution pattern and the type of sugar moiety, both for spontaneous and microbiota-dependent degradation.
Anthocyanins are completely degraded in a model of the human colon by a combination of spontaneous and microbiota-dependent processes.
食用膳食花色苷具有多种健康益处。然而，花色苷的生物利用度较低，大多数摄入的花色苷会进入结肠，在那里它们会降解为主要的吸收形式——小分子酚类代谢物。目前对肠道中花色苷的降解过程以及人类肠道微生物群的作用知之甚少。本研究旨在确定花色苷在人体结肠中自发降解和微生物群依赖性降解的作用。
将从黑米和越橘中纯化的花色苷提取物在体外接种人粪便的pH控制结肠模型中孵育24小时，并使用高效液相色谱-二极管阵列检测器（HPLC-DAD）分析花色苷。研究表明，花色苷的损失既有自发发生的，也有肠道微生物群代谢的结果。研究观察到自发降解存在高度变异性，但总降解（包括微生物群依赖性成分）仅有适度变化。花色苷的降解率还显示出取决于B环取代模式和糖部分的类型，无论是自发降解还是微生物群依赖性降解。
在人体结肠模型中，花色苷通过自发和微生物群依赖性过程的组合被完全降解。
