pH值对11S球蛋白结构与凝胶性的影响

研究了豫豆-25 11S球蛋白凝胶质构特性与pH值的关系。结果表明:pH值对豫豆-25 11S球蛋白凝胶的形成及质构特性影响较大,酸性条件下的凝胶与碱性条件下的有较大的差异。扫描电子显微镜(SEM)观察及傅立叶交换红外光谱(FTIR)分析显示:在远离等电点的碱性条件下,11S球蛋白凝胶具有较高有序性的微观结构,它们的微观结构均匀,只有少量的聚合物;酸性条件下的凝胶的微观结构有序性低于碱性条件下的凝胶,离等电点较近pH的凝胶聚合物较多,微观结构有序性低;pH4.15的凝胶要比pH7.5的含有更多的无规则卷曲结构。凝胶蛋白二级结构中无规则卷曲向有序结构的转化,微观结构趋于有序。

Effect of temperature on structure and gelling characteristics of yu-25 soybean 11S globulin

Relationships between texture characterization of yu-25 soybean 11S globulin gels and pH had been studied thoroughly. These experimental results showed that pH affected textural properties intensively. Gels formed in alkaline and acidic conditions had obvious differences. By scanning electron microscopy (SEM) and fourier transform infrared spectroscopy (FTIR), under different pH conditions, microstructures of 11S globulin had obvious differences. The gels at the alkaline pH far from the pI had a microstructure more homogeneous and less aggregated than those at the pH near the pI. The gel prepared at pH4.15 contained more random coil than those prepared at pH7.5.