金针菇多糖对大豆分离蛋白凝胶的增强作用及其结构表征

Enhancing Effect of Flammulina velutipes Polysaccharide on Gelation Properties of Soybean Protein Isolate and Structural Characterization of Mixed Gels

通过将金针菇多糖(Flammulina velutipes polysaccharide,FVP)添加到大豆分离蛋白(soy protein isolate,SPI)水凝胶中并进行热处理以提高SPI水凝胶强度、持水性和热稳定性。通过对二三级结构及分子间作用力的检测,进一步分析FVP-SPI水凝胶的稳定性。结果显示:热处理及添加FVP显著提高SPI水凝胶的持水能力,热变性焓ΔH提高了25.46%,水凝胶稳定性显著提高。疏水相互作用、二硫键和静电相互作用是形成热处理FVP-SPI水凝胶的主要作用力。FVP的加入提高了静电相互作用,使水凝胶中α-螺旋向β-折叠转变,SPI中色氨酸暴露于表面,疏水性增强。FVP对SPI水凝胶的增强作用为SPI水凝胶的开发应用提供一定参考。

Flammulina velutipes polysaccharide(FVP) was added to soy protein isolate(SPI) hydrogels and subjected to heat treatment to improve the gel strength, water-holding capacity and thermal stability. The stability of FVP-SPI hydrogels was further analyzed in terms of their secondary and tertiary structures and intermolecular forces. The results showed that heat treatment and addition of FVP significantly improved the water-holding capacity of SPI hydrogels, and increased the enthalpy change of denaturation(ΔH) by 25.46%, thereby significantly improving hydrogel stability. Hydrophobic interactions, disulfide bonds and electrostatic interactions were the major driving forces for the formation of heat-induced FVP-SPI hydrogels. The addition of FVP improved the electrostatic interactions and caused transformation of α-helix into β-sheets in the hydrogels, surface exposure of the tryptophan residues in SPI and enhanced hydrophobicity. The enhancement of SPI hydrogels by FVP provides a reference for the development and application of SPI hydrogels.