为探究碱性条件下pH对马鲛鱼肌球蛋白热聚集行为的影响，以马鲛鱼肌球蛋白为研究对象，探究在加热条件下pH（7.0、8.0、9.0）对肌球蛋白的结构和理化性质（溶解度、浊度、二级结构、总巯基含量、表面疏水性）的影响，未加热组作为空白对照组。结果表明：对照组肌球蛋白在pH（7.0、8.0、9.0）下溶解度从68.00%升高到82.00%、浊度变化不明显；加热组则有较大差异，溶解度从30.00%增加到94.00%，浊度吸光值从0.49降低到0.23；加热组pH 9.0的肌球蛋白α-螺旋含量减少，在所有组中含量最低，为45.60%，β-折叠含量增加，为10.60%；加热组的巯基含量呈下降趋势，由70.45 nmol/mg减少到50.11 nmol/mg，碱性pH下的蛋白质有助于巯基向分子间和分子内二硫键的转化；随着pH值的增加，对照组肌球蛋白的表面疏水性系数依次增加，而加热组下降，但加热组肌球蛋白的表面疏水性系数仍然远高于对照组。综上所述，通过探究碱性条件下肌球蛋白热聚集体的性质，有助于对其热聚集进行调控，获得一种热稳定性较好的肌球蛋白溶液，对以后研究其作为乳化剂添加到食品中有重要意义。

In order to explore the effect of alkaline pH on the thermal aggregation behavior of mackerel myosin, mackerel myosin was used to explore the effect of pH (7.0, 8.0, 9.0) on the structure and structure of myosin under heating conditions. For the influence of physical and chemical properties (solubility, turbidity, secondary structure, total sulfhydryl content, surface hydrophobicity), the unheated group was used as a blank control group. The results showed that the solubility of myosin in the control group increased from 68.00% to 82.00% at pH (7.0, 8.0, 9.0), and the turbidity did not change significantly; there was a big difference in the heating group, and the solubility increased from 30.00% to 94.00% , The turbidity absorbance value decreased from 0.49 to 0.23; the content of myosin α-helix at pH 9.0 in the heating group decreased, and the content was the lowest among all groups, at 45.60%, and the β-sheet content increased at 10.60%; the sulfhydryl group content of the heating group showed a downward trend, from 70.45 nmol/mg to 50.11 nmol/mg. The protein at alkaline pH facilitates the conversion of sulfhydryl groups into intermolecular and intramolecular disulfide bonds; as the pH value increases, for the myospheroids of the control group, the surface hydrophobicity coefficient of the protein increased successively, while the heating group decreased, but the surface hydrophobicity coefficient of myosin in the heating group was still much higher than that of the control group. In summary, by exploring the properties of myosin thermal aggregates under alkaline conditions, it will conducive to regulate their thermal aggregation and obtain a myosin solution with better thermal stability. The addition of emulsifiers to food is of great significance.

辽宁省自然科学基金项目（2021-MS-147）；国家重点研发计划重点专项（2018YFD0400600）