Insights on the structure of caseinate particles based on surfactants-induced dissociation
Insights on the structure of caseinate particles based on surfactants-induced dissociation
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基于表面活性剂诱导解离的酪蛋白酸盐颗粒结构的见解
DOI：
10.1016/j.foodhyd.2020.105766
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发表时间：
2020-07
影响因子：
10.7
通讯作者：
Yang Sun
中科院分区：
文献类型：
--
作者：
Feng Cao;Yuanyuan Xia;Dan Chen;Ning Xu;Yacine Hemar;Na Li;Yang Sun
酪蛋白是从牛奶中的主要蛋白质酪蛋白中提取出来的，在水溶液中形成聚集体。本文采用量热、光谱、散射和电子显微镜相结合的方法，研究了不同烷基链烷基三甲基溴化铵(CnTAB，n=10、12、14、16)对酪蛋白粒子内部结构的影响。结果表明，酪蛋白中至少有Trp、Tyr、Phe、Leu和Ala残基的疏水环境随着CnTAB链长的增加而增加。CnTAB诱导酪蛋白聚集体的解离可能是由于CnTAB的溴化铵基团通过静电作用与相反电荷的κ-酪蛋白结合，以及CnTAB烷基链与钙敏感酪蛋白的富P，Q部分(αS1-，αS2-和β-酪蛋白)结合，从而提供了更有利的非共价相互作用，如氢键和疏水相互作用。这些相互作用导致酪蛋白的骨架到骨架的相互作用被破坏，从而使酪蛋白聚集体解离成更小的酪蛋白簇。当加入10 mM EDTA时，酪蛋白-CnTAB复合体的大小分布由于酪蛋白聚集体中钙离子的耗尽而发生较大程度的破坏，这表明CnTAB与酪蛋白的结合可能不会破坏酪蛋白上的磷酸盐中心。根据分子动力学(MD)模拟，αS1-酪蛋白-CnTAB的“项链和珠子”结构和结合数随着CnTAB烷基的增加而增加，为αS1-酪蛋白-CnTAB提供了更多的亲水头基和静电斥力。电子显微镜图像显示，加入CnTAB后，酪蛋白纳米颗粒失去了最初的形态，解离成直径在~30到~100 nm之间的较小的酪蛋白聚集体。酪蛋白聚集体由直径约10 nm的无定形致密团簇组成，团簇间距约为20~30 nm。这项工作通过利用表面活性剂诱导的解离提供了对酪蛋白颗粒结构的分子洞察。
Caseinate is derived from casein, the major protein in milk, and forms aggregates in aqueous solution. Here, the internal structure of caseinate particles based on dissociation induced by the different alkyl chainn-alkyl trimethylammonium bromides (CnTAB,n= 10, 12, 14, 16) was investigated by the combination of calorimetric, spectral, scattering and electron microscopic techniques. The results suggested the hydrophobic environment of, at least, Trp, Tyr, Phe, Leu and Ala residues in caseinate increased with increasing the chain length of CnTAB. The dissociation of caseinate aggregates induced by CnTAB was possibly due to the binding of ammonium bromide groups of CnTAB with opposite charged κ-casein via electrostatic interactions, as well as the binding of CnTAB alkyl chain with the P,Q-rich portion of calcium-sensitive caseins (αs1-,αs2-and β-casein) which provided more energetically favorable non-covalent interactions, such as hydrogen bonding and hydrophobic interactions. These interactions resulted in the disruption of backbone-to-backbone interactions of caseins and thus the dissociation of the caseinate aggregates into smaller caseinate clusters. When 10 mM EDTA was added, the size distribution of caseinate-CnTAB complexes exhibited a greater extent of disruption due to the depletion of calcium ions in the caseinate aggregate, suggesting that the binding of CnTAB with casein may not disrupt the phosphate centers on caseins. According to molecular dynamics (MD) simulations, the “necklace and bead” structure of αs1-casein-CnTAB and the binding number increased with increasing the alkyl chain of CnTAB, providing more hydrophilic headgroups and electrostatic repulsion for αs1-casein-CnTAB complex. Electron microscopy images showed that, upon addition of CnTAB, caseinate nanoparticles lost their initial morphology dissociating into smaller caseinate aggregates with diameters ranging from ~30 to ~100 nm. The caseinate aggregates were made of amorphous denser clusters with a diameter of ~10 nm, and the distance between the clusters was observed as ~20–30 nm. This work provides molecular insights into the structure of caseinate particles by exploiting surfactants-induced dissociation.
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影响因子：
10.7
作者：
A. Pitkowski;T. Nicolai;D. Durand
通讯作者：
A. Pitkowski;T. Nicolai;D. Durand
影响因子：
10.7
作者：
Norbert Raak;C. Schöne;H. Rohm;D. Jaros
通讯作者：
Norbert Raak;C. Schöne;H. Rohm;D. Jaros
影响因子：
1.7
作者：
T. Ishida;Yukiko Toda;M. Tarui;M. Doi;M. Inoue
通讯作者：
T. Ishida;Yukiko Toda;M. Tarui;M. Doi;M. Inoue
影响因子：
10.9
作者：
Daiwu Chen;Q. Xie;Xueqin Jiang;S. Yao
通讯作者：
Daiwu Chen;Q. Xie;Xueqin Jiang;S. Yao
DOI：
10.1021/la051509g
发表时间：
2005-10
期刊：
Langmuir : the ACS journal of surfaces and colloids
影响因子：
--
作者：
G. Ray;I. Chakraborty;S. Ghosh;S. P. Moulik;R. Palepu
通讯作者：
G. Ray;I. Chakraborty;S. Ghosh;S. P. Moulik;R. Palepu