摘要
本文在pH6.5磷酸盐缓冲溶液中研究了热变性前后牛乳铁蛋白(bovine lactoferrin,LF)和α-乳白蛋白(α-lactalbumin,ALA)之间的自组装行为。采用ζ-电位、浊度法、动态光散射、光学显微镜、荧光光谱和红外色谱等方法进行表征。结果表明,与天然LF和ALA自组装复合物相比,热变性LF和ALA自组装复合物的ζ-电位较低。天然LF与ALA可以自组装可形成纳米颗粒,粒径最大为(35.24±0.82)nm;经过热变性的LF与ALA自组装形成超分子结构,通过调整ALA浓度,可以得到亚微米和微米颗粒,颗粒粒径最大为(4.11±0.14)μm。天然LF与ALA的复合物均为球状聚集体,分布均一;而热变性LF与ALA的复合物则为网状聚集体,分布不均一。ALA的添加增强了LF中色氨酸残基的疏水性。LF中的C=O和C-N基团均参与了与ALA25℃的相互作用。本研究为构建新型双蛋白自组装体及理解双蛋白组装机制提供了理论依据。
The interaction between natural and thermally modified bovine lactoferrin(LF)andα-lactalbumin(ALA)was investigated at pH6.5 in phosphate buffer.ζ-potential,turbidimetric method,dynamic light scattering,optical microscopy,fluorescence spectrum and infrared chromatography were used for characterization.The results showed that theζ-potential values of thermally modified LF-ALA complexes were lower than that of natural LF-ALA complexes.Natural LF and ALA could self assemble to form nanoparticles with a maximum size of(35.24±0.82)nm.The thermally modified LF and ALA could self assemble to form supramolecular structure.By adjusting the concentration of ALA,submicrometer and micrometer particles could be obtained.The maximum particle size was(4.11±0.14)μm.The complexes of natural LF and ALA were spherical aggregates with uniform distribution,while the complexes of the thermally modified LF and ALA were large aggregates with uneven distribution.ALA enhanced the hydrophobicity of tryptophan residues in LF.ALA25℃interacted with the C=O and C-N groups in the LF structural subunits.This study provides a theoretical basis for the construction of novel double protein selfassembly and understanding of the mechanism of double protein assembly.
作者
许琳霜
屈晓清
曾小凤
郑钰斐
张妍
王婷
张红
Nazarenko Yulia
李波
杨伟
XU Lin-shuang;QU Xiao-qing;ZENG Xiao—feng;ZHENG Yu-fei;ZHANG Yan;WANG Ting;ZHANG Hong;NAZARENKO Yulia;LI Bo;YANG Wei(School of Food Science,Henan Institivte of Science and Technology,Xinxiang 453003,China;Technology of Food Department,Sumy National Agrarian University,Sumy 40021,Ukraine)
出处
《食品工业科技》
CAS
北大核心
2020年第15期15-20,28,共7页
Science and Technology of Food Industry
基金
国家自然科学基金青年科学基金项目(31601511)
河南科技学院博士启动基金项目(205010616001)。
关键词
乳铁蛋白
Α-乳白蛋白
超分子结构
颗粒特性
自组装机制
lactoferrin
α-lactalbumin
supramolecular structure
particle properties
self-assembly mechanism
