Shehata Emad, Percival Jasmine, Philo Mark, Needs Paul W, Clifford Michael N, Kroon Paul A
Quadram Institute Bioscience, Norwich Research Park, Norwich NR4 7UQ, UK; Chemistry of Flavour and Aroma Department, Food Industry and Nutrition Research Institute, National Research Centre, 33 El Buhouth St., Dokki, 12622 Cairo, Egypt.
Quadram Institute Bioscience, Norwich Research Park, Norwich NR4 7UQ, UK.
Food Chem. 2025 Sep 15;486:144614. doi: 10.1016/j.foodchem.2025.144614. Epub 2025 May 5.
It was recently reported that degradation of anthocyanins in the anaerobic human colon occurs via both microbiota-dependent and spontaneous processes. However, the existing literature only describes the spontaneous degradation of anthocyanins in aerobic conditions. We investigated the loss of cyanidin-3-O-glucoside (Cy3Glc) over time under aerobic and anaerobic conditions. In anaerobic conditions, spontaneous breakdown products were consistent with Cy3Glc undergoing a classic pH-dependent transformation to colourless intermediates (i.e., cyanidin (Cy) hemiketal-glucoside, Cy chalcone-glucoside, Cy chalcone quinone-glucoside, 2,4,6-trihydroxyethenylbenzene-glucoside), but no other breakdown products. In contrast, under aerobic conditions, in addition to the pH-dependent intermediates, multiple other breakdown products were identified, including the previously reported protocatechuic acid and phloroglucinaldehyde, and several products of oxidation reactions reported for the first time (coumarin-glucoside, 2,4,6-trihydroxyphenylacetic acid, 2,4,6-trihydroxyphenylglyoxylic acid, and 3,4-dihydroxyphenylglyoxylic acid). These observations show degradation of anthocyanins is completely different in aerobic compared to anaerobic conditions, and useful information of the spontaneous degradation of anthocyanins cannot be obtained using aerobic conditions.
最近有报道称，花青素在人体厌氧结肠中的降解通过微生物群依赖和自发过程发生。然而，现有文献仅描述了花青素在有氧条件下的自发降解。我们研究了有氧和厌氧条件下矢车菊素 - 3 - O - 葡萄糖苷（Cy3Glc）随时间的损失情况。在厌氧条件下，自发分解产物与Cy3Glc经历经典的pH依赖性转化为无色中间体（即矢车菊素（Cy）半缩酮 - 葡萄糖苷、Cy查耳酮 - 葡萄糖苷、Cy查耳酮醌 - 葡萄糖苷、2,4,6 - 三羟基乙烯基苯 - 葡萄糖苷）一致，但没有其他分解产物。相比之下，在有氧条件下，除了pH依赖性中间体外，还鉴定出多种其他分解产物，包括先前报道的原儿茶酸和间苯三酚醛，以及首次报道的几种氧化反应产物（香豆素 - 葡萄糖苷、2,4,6 - 三羟基苯乙酸、2,4,6 - 三羟基苯乙醛酸和3,4 - 二羟基苯乙醛酸）。这些观察结果表明，与厌氧条件相比，花青素在有氧条件下的降解完全不同，并且使用有氧条件无法获得花青素自发降解的有用信息。
