The influence of high-pressure treatment on the molecular structure of lactoferrin
高压处理对乳铁蛋白分子结构的影响

摘要

乳铁蛋白具有多种生物活性，在食品、医药等领域具有广泛应用前景。但其分子结构和功能特性易受外界环境影响。本文采用不同压力条件（包括超静压、均质和微射流）对乳铁蛋白进行处理，并测量了处理前后乳铁蛋白的整体粒径、分子尺寸及电位等参数的变化。结果显示，均质1200bar下乳铁蛋白粒径最高，超静压、微射流能够降低蛋白粒径。不同的超静压压力对乳铁蛋白粒径无显著影响，微射流2000bar时乳铁蛋白粒径显著低于微射流1600bar。不同的高压处理方式及压力水平对乳铁蛋白分子的尺寸无明显影响，分子尺寸均维持在2.21~2.51nm之间。超静压和微射流处理可以降低乳铁蛋白影响ζ-电位，而均质1500bar处理时乳铁蛋白的ζ-电位能够保持不变。乳铁蛋白在不同高压处理条件下光学性质具有一定的稳定性。本文的研究为乳铁蛋白在工业化应用中的稳定性优化提供了理论依据和技术参考。

Abstract

Lactoferrin has a variety of biological activities, and has wide application prospects in food, medicine and other fields. However, its molecular structure and functional properties are easily affected by the external environment. In this paper, lactoferrin was treated under different pressure conditions (including overstatic pressure, homogeneity and microjet), and the changes of global particle size, molecular size and potential of lactoferrin before and after treatment were measured. The results showed that the particle size of lactoferrin was the highest at the homogeneous 1200bar, and the particle size of lactoferrin could be reduced by superstatic pressure and microjet. Different superstatic pressure has no significant effect on the particle size of lactoferrin, and the particle size of lactoferrin is significantly lower than that of microjet 1600bar when microjet is 2000bar. Different high-pressure treatment methods and pressure levels had no obvious effect on the size of lactoferrin molecules, and the molecular size remained between 2.21 and 2.51nm. Superstatic pressure and microjet treatment can reduce the effect of lactoferrin on zeta - potential, but the zeta - potential of lactoferrin can remain unchanged when treated with 1500bar. The optical properties of lactoferrin are stable under different high-pressure conditions. The research in this paper provides theoretical basis and technical reference for the stability optimization of lactoferrin in industrial application.