高压脉冲电场对β-乳球蛋白结构和抗原性的影响

Effect of pulsed electric fields on structure and antigenicity of β-lactoglobulin

采用电泳、圆二色谱、荧光光谱及酶联免疫吸附法,研究不同高压脉冲电场(pulsed electric fields,PEF)处理条件对β-乳球蛋白(β-lactoglobulin,β-Lg)结构和抗原性的影响。结果表明:PEF处理对β-Lg分子质量无明显影响,但对其二级结构、三级结构和抗原性有显著影响,且其抗原性变化与结构变化密切相关。β-Lg的β-折叠含量、内源性荧光强度、表面疏水性和抗原性均随处理时间的延长呈先增加后降低的趋势,且均在25k V/cm处理30μs的条件下达到最大值,此时抗原性为1 344μg/m L。同时,当处理时间为210μs时,β-Lg的抗原性降低了约58%。这表明,PEF为制备低过敏性β-Lg提供了一种潜在的新方法。

The aim of this study was to research the effect of pulsed electric fields（ PEF） on structure and allergenicity of β-lactoglobulin（ β-Lg）. SDS-PAGE,circular dichroism spectra,fluorescence spectra. and indirect competitive enzyme-linked immunosorbent assay were used to measure the structure and antigenicity,respectively. The results showed that PEF had no significant influence on the molecular weight of β-Lg. However,it had an significant effect on secondary structure,tertiary structure and antigenicity. Moreover,the change of antigenicity was closely related to that of the structure induced by PEF. The content of β-sheet,intrinsic fluorescence intensity,surface hydrophobicity and antigenicity were first increased and then decreased with the increasing of PEF treating time. The allergenicity of β-Lg reached up to 1344μg / m L when treated at 25 k V / cm for 30 μs. And it was decreased about 58% at210 μs. This indicated that the PEF could be used in producing low allergic milk.