Gtari Wala, Aschi Adel, Nicolai Taco, de Freitas Rilton Alves
Polymères, Colloïds, Interfaces, UMR CNRS Université du Maine, 72085 Le Mans Cedex 9, France; Université de Tunis El Manar, Faculté des Sciences de Tunis, LR99ES16 Laboratoire Physique de la Matière Molle et dela Modélisation Électromagnétique, 2092, Tunis, Tunisia.
Université de Tunis El Manar, Faculté des Sciences de Tunis, LR99ES16 Laboratoire Physique de la Matière Molle et dela Modélisation Électromagnétique, 2092, Tunis, Tunisia.
Int J Biol Macromol. 2016 Nov;92:357-361. doi: 10.1016/j.ijbiomac.2016.07.045. Epub 2016 Jul 15.
Core-shell particles were formed by mixing in aqueous solution the neutral polysaccharide xyloglucan (XG) with microgels. The last one was obtained by heating the whey protein β-lactoglobulin (β-LG) in the presence of CaCl. XG adsorbed spontaneously unto the microgels at pH<5.6. The amount of bound XG per protein was determined using a combination of centrifugation and size exclusion chromatography. It increased linearly with increasing XG concentration. The fraction of XG that adsorbed increased with decreasing pH. The formation of the XG shell inhibited large scale flocculation of the particles, that causes precipitation for naked microgels, close to their isoionic point. The thickness of the XG shell was estimated by measurement of the hydrodynamic radius using dynamic light scattering. The extent of binding depended on the pH history during mixing showing that the protein/XG complex was not in thermodynamic equilibrium.
通过在水溶液中将中性多糖木葡聚糖（XG）与微凝胶混合，形成了核壳颗粒。微凝胶是通过在氯化钙存在下加热乳清蛋白β-乳球蛋白（β-LG）获得的。在pH<5.6时，XG自发吸附到微凝胶上。使用离心和尺寸排阻色谱相结合的方法测定了每个蛋白质结合的XG量。它随XG浓度的增加呈线性增加。吸附的XG分数随pH值降低而增加。XG壳的形成抑制了颗粒的大规模絮凝，而对于裸微凝胶，在其等离子点附近会导致沉淀。通过使用动态光散射测量流体动力学半径来估计XG壳的厚度。结合程度取决于混合过程中的pH历史，这表明蛋白质/XG复合物不是处于热力学平衡状态。
