TUM School of Life Sciences, Technical University of Munich (TUM), 85354 Freising, Germany.
Fraunhofer Institute for Process Engineering and Packaging (IVV), 85354 Freising, Germany.
Nutrients. 2021 Apr 21;13(5):1398. doi: 10.3390/nu13051398.
Soluble dietary fibers (SDF) are known to reduce the post-prandial plasma glucose levels. However, the detailed mechanisms of this reduced glucose release in the human gut still remain unclear. The aim of our study was to systematically investigate the effect of different types of SDF on glucose release in an in vitro model as a prerequisite for the selection of fibers suitable for application in humans. Three types of carboxymethyl cellulose (CMC) were used to investigate the correlations between fiber concentration, molecular weight (), and viscosity on diffusion of glucose using a side-by-side system. CMC solutions below the coil overlap (*) influenced the glucose diffusivity only marginally, whereas at concentrations above * the diffusion of glucose was significantly decreased. Solutions of lower exhibited a lower viscosity with lower glucose diffusion compared to solutions with higher CMC, attributed to the higher density of the solutions. All CMC solutions showed a systematic positive deviation from Stokes-Einstein behavior indicating a greater rise in viscosity than reduction in diffusion. Therefore, our results pave the way for a new approach for assessing glucose diffusion in solutions comprising dietary fibers and may contribute to further elucidating the mechanisms of post-prandial plasma glucose level reduction.
可溶性膳食纤维（SDF）已知可降低餐后血糖水平。然而，其在人体肠道中降低葡萄糖释放的详细机制仍不清楚。我们的研究旨在系统地研究不同类型的 SDF 对体外模型中葡萄糖释放的影响，作为选择适合人类应用的纤维的前提条件。使用侧流系统，我们使用三种羧甲基纤维素（CMC）来研究纤维浓度、分子量（）和粘度对葡萄糖扩散的相关性。在 coil overlap (*) 以下的 CMC 溶液对葡萄糖扩散的影响可以忽略不计，而在 * 以上的浓度下，葡萄糖的扩散则显著降低。与具有较高 CMC 的溶液相比，具有较低 的溶液具有较低的粘度和较低的葡萄糖扩散，这归因于溶液的密度较高。所有 CMC 溶液均表现出与 Stokes-Einstein 行为的系统正偏差，表明粘度升高幅度大于扩散降低幅度。因此，我们的结果为评估包含膳食纤维的溶液中葡萄糖扩散的新方法铺平了道路，并可能有助于进一步阐明降低餐后血糖水平的机制。
