van Deuren Thirza, Umanets Alexander, Venema Koen, Moreno Luis L, Zoetendal Erwin G, Canfora Emanuel E, Blaak Ellen E
Human Biology, Institute of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University Medical Center+, Maastricht, the Netherlands'.
Chair Group Youth Food and Health, Faculty of Science and Engineering, Maastricht University-Campus Venlo, Venlo, the Netherlands; Centre for Healthy Eating & Food Innovation (HEFI), Maastricht University-Campus Venlo, Venlo, the Netherlands.
Food Res Int. 2025 May;209:116271. doi: 10.1016/j.foodres.2025.116271. Epub 2025 Mar 16.
Evidence suggests that increased distal short-chain fatty acid (SCFA) production beneficially impacts metabolic health. However, indigestible carbohydrate availability is limited in the distal colon; consequently, microbes shift toward protein fermentation, often linked to adverse metabolic health effects. We aimed to identify specific fiber(s) that promote saccharolytic fermentation in the distal colon and thereby may (partially) inhibit proteolytic fermentation.
Potato-fiber, pectin, and inulin were studied individually and in combination against a high (predigested) protein background using an in vitro model of the colon (TIM-2) inoculated with pooled, standardized fecal microbiota from individuals with overweight/obesity. Microbiota composition and activity were assessed at different timepoints to simulate the travel throughout the colon (proximal: 0-8 h, distal: 8-24 h) and compared to a high protein (HP)_control, receiving only proteins.
Fiber addition increased total SCFA production compared to HP_control (52.11 ± 1.49 vs 27.07 ± 0.26 mmol) whereas total branched-chain fatty acids (BCFA; a marker for protein fermentation) production only slightly decreased (3.31 ± 0.10 vs 4.18 ± 0.40 mmol). Combining potato-fiber and pectin led to the highest total and distal SCFA production and distal SCFA:BCFA. Fiber addition attenuated HP-induced increases in several bacterial taxa including Mogibacterium and Coprococcus, independent of fiber type. Additionally, time- and fiber-specific microbial signatures were identified: inulin increased Bifidobacterium (proximal) relative abundance and pectin and/or potato-fiber increased Prevotella 9 (distal) relative abundance.
The most marked increase in distal colonic SCFA production was induced by combining potato-fiber and pectin. Further research should elucidate whether this switch toward saccharolytic fermentation translates into beneficial metabolic health effects in humans.
有证据表明，远端短链脂肪酸（SCFA）产量增加对代谢健康有有益影响。然而，远端结肠中难消化碳水化合物的可用性有限；因此，微生物会转向蛋白质发酵，这通常与不良的代谢健康影响有关。我们旨在确定能促进远端结肠中糖分解发酵从而可能（部分）抑制蛋白水解发酵的特定纤维。
使用结肠体外模型（TIM-2），以超重/肥胖个体的混合标准化粪便微生物群接种，在高（预消化）蛋白背景下分别单独研究和组合研究马铃薯纤维、果胶和菊粉。在不同时间点评估微生物群组成和活性，以模拟在整个结肠中的移动（近端：0 - 8小时，远端：8 - 24小时），并与仅接受蛋白质的高蛋白（HP）对照进行比较。
与HP对照相比，添加纤维增加了总SCFA产量（52.11±1.49对27.07±0.26毫摩尔），而总分支链脂肪酸（BCFA；蛋白质发酵的标志物）产量仅略有下降（3.31±0.10对4.18±0.40毫摩尔）。将马铃薯纤维和果胶组合导致总SCFA和远端SCFA产量最高，以及远端SCFA:BCFA最高。添加纤维减弱了HP诱导的包括毛杆菌属和粪球菌属在内的几种细菌类群的增加，与纤维类型无关。此外，还确定了时间和纤维特异性的微生物特征：菊粉增加了双歧杆菌属（近端）相对丰度，果胶和/或马铃薯纤维增加了普雷沃菌属9（远端）相对丰度。
马铃薯纤维和果胶组合诱导远端结肠SCFA产量最显著增加。进一步的研究应阐明这种向糖分解发酵的转变是否会对人类代谢健康产生有益影响。
