Will Roman, Rein Claudia, Frank Jan, Malan Johanita
Department of Food Biofunctionality, University of Hohenheim, Stuttgart, Germany.
Department of Food Technology, Fulda University of Applied Sciences, Fulda, Germany.
J Sci Food Agric. 2025 Apr;105(6):3406-3415. doi: 10.1002/jsfa.14109. Epub 2025 Jan 7.
Understanding the size and surface charge (ζ-potential) of particles in the mixed micellar fraction produced by in vitro digestion is crucial to understand their cellular absorption and transport. The inconsistent presentation of micellar size data, often limited to average particle diameter, makes comparison of studies difficult. The present study aimed to assess different size data representations (mean particle diameter, relative intensity- or volume-weighted size distribution) to better understand physiological mixed micelle characteristics and to provide recommendations for size reporting and sample handling.
Dietary compounds (RRR-α-tocopherol, retinyl-palmitate, β-carotene, curcumin and naringenin) underwent a simplified in vitro digestion, whereas foods (spinach and red cabbage) were subjected to both a simplified and the INFOGEST 2.0 digestions. Dynamic light scattering was used to measure size and surface charge of the mixed micelles. A significant percentage of particles above the 200 nm filter cut-off was observed, indicating aggregation and dynamic size changes in the mixed micellar fraction. Freezing of the mixed micelles notably enhanced the aggregation.
The determination of particle size in polydisperse mixed micellar fractions is challenging, and relying solely on average particle diameter can be misleading. Especially in more polydisperse samples, parameters such as polydispersity index and volume-weighted distribution should accompany average particle diameter data. To minimize the effect of freezing on particle size, we recommend filtering the digesta after storage (freezing), as this leads to similar size distribution compared to mixed micellar fraction measured directly after digestion. © 2025 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
了解体外消化产生的混合胶束部分中颗粒的大小和表面电荷（ζ电位）对于理解其细胞吸收和转运至关重要。胶束大小数据呈现不一致，通常仅限于平均粒径，这使得研究之间的比较变得困难。本研究旨在评估不同的大小数据表示方法（平均粒径、相对强度或体积加权大小分布），以更好地理解生理混合胶束的特征，并为大小报告和样品处理提供建议。
膳食化合物（RRR-α-生育酚、视黄醇棕榈酸酯、β-胡萝卜素、姜黄素和柚皮素）进行了简化的体外消化，而食物（菠菜和红甘蓝）则进行了简化消化和INFOGEST 2.0消化。使用动态光散射测量混合胶束的大小和表面电荷。观察到有相当比例的颗粒大于200 nm的滤膜截留值，表明混合胶束部分存在聚集和动态大小变化。混合胶束的冷冻显著增强了聚集。
多分散混合胶束部分中颗粒大小的测定具有挑战性，仅依赖平均粒径可能会产生误导。特别是在多分散性更高的样品中，除了平均粒径数据外，还应附上多分散指数和体积加权分布等参数。为了尽量减少冷冻对颗粒大小的影响，我们建议在储存（冷冻）后对消化物进行过滤，因为与消化后直接测量的混合胶束部分相比，这样得到的大小分布相似。© 2025作者。《食品与农业科学杂志》由John Wiley & Sons Ltd代表化学工业协会出版。
