超高压处理对S-卵白蛋白构象与功能特性的影响

采用激光拉曼光谱、荧光光谱分析超高压(UHP)对S-卵白蛋白构象的影响,并考察其对溶解性、乳化性和起泡能力等功能特性的影响.结果表明,经UHP处理后S-卵白蛋白的分子量分布没有明显变化.随着压力增加,无规卷曲含量逐渐增加,二硫键构象变化使蛋白稳定性降低,酪氨酸残基包埋于侧链中,紧密折叠结构得以舒展.经100 MPa处理后S-卵白蛋白的荧光强度略有增强,此后急剧下降,无峰位位移现象,说明UHP引起蛋白分子构象变化.S-卵白蛋白的溶解性、乳化性及起泡能力等功能特性均随压力增加而明显改善,以300 MPa处理较为理想,此后压力增加至500 MPa时反而下降.

Effect of Ultra High Pressure on Conformation and Functional Properties of S-ovalbumin

The effect of ultra high pressure (UHP) treatment on conformation of S-ovalbumin was studied with Raman spectra and fluorescence spectra analysis. The effect of UHP on some functional properties of S-ovalbumin, such as solubility, emulsibility and foamability, were also investigated. It was showed that no significant changed in the molecular weight distribution of S-ovalbumin after UHP. Along with the increase of pressure, the content of random coil of S-ovalbumin was increasing gradually, the stability decreasing owing to the conformation change of disulfide bonds, and tyrosine was buried in the side chain, accordingly the compactly plate sheet structure was to become loose. The fluorescence intensity showed a slight increase after UHP under 100MPa, but then a sharp decline with the increase of pressure, no shift of the fluorescence emission peak happening, so it was pointed out that UHP induced conformational change. The solubility, emulsibility and foamability properties of S-ovalbumin had been improved significantly with the increase of pressure, and achieved the best effect at 300MPa. Then, there was a drop down when the pressure was 500MPa.