精氨酸对微波场下低盐鲟鱼肌原纤维蛋白预凝胶化的影响  

Effect of Arginine on Microwave-Induced Pre-gelation of Sturgeon Myofibrillar Protein under Low Salt Condition

作　　者：石彤[1] 解钰 张昊 王鑫[1] 李梦哲 高瑞昌[1] SHI Tong;XIE Yu;ZHANG Hao;WANG Xin;LI Mengzhe;GAO Ruichang(School of Food and Biological Engineering,Jiangsu University,Zhenjiang 212013,China)

机构地区：[1]江苏大学食品与生物工程学院,江苏镇江212013

出　　处：《食品科学》2025年第7期51-60,共10页Food Science

基　　金：国家自然科学基金青年科学基金项目(32202090);江苏省基础研究计划自然科学基金——青年基金项目(BK20220520);国家现代农业产业技术体系岗位科学家专项(CARS-46)。

摘　　要：为探究精氨酸(Arg)对微波场下低盐肌原纤维蛋白预凝胶化的影响,利用200 W微波分别在不同Arg浓度条件下加热肌原纤维蛋白1、3 min和5 min(<40℃),对该加热过程中肌原纤维蛋白的理化特性、结构特性、分子间作用力和形态学特性进行研究。结果表明,肌原纤维蛋白溶液的溶解度随微波时间的延长而降低,且在相同的微波时间下,适宜浓度的Arg能够显著提高其溶解度(P<0.05)。在微波处理5 min时,随Arg浓度的增加肌原纤维蛋白浊度显著降低(P<0.05)。肌原纤维蛋白粒径随Arg浓度的增加而减小;且通过原子力显微镜观察到Arg抑制了微波加热过程中较大蛋白聚集簇的形成。未添加Arg溶液的肌原纤维蛋白经微波加热3 min,其离子键和氢键含量显著降低,疏水相互作用和二硫键含量显著增加(P<0.05);40 mmol/L Arg抑制了蛋白分子间的离子键和疏水相互作用,增强了氢键和二硫键的贡献。分子动力学模拟结果显示,300 K模拟系统中Arg与肌球蛋白结合后,均方根偏差约从0.52 nm增大至5.85 nm;Arg-肌球蛋白复合物与肌球蛋白自身相比具有较高的回旋半径。以上结果表明,Arg促进了低盐条件下肌原纤维蛋白聚集体的解聚,使其在微波场下的聚集特征由原来以较大蛋白簇为主转变为以较小颗粒为主;此外,肌球蛋白的结构紧密性因Arg的结合而下降,蛋白构象更加松散,为其在后续凝胶增强阶段的进一步交联提供充足的储备条件。In order to investigate the effect of arginine(Arg)on the microwave-induced pre-gelation of myofibrillar protein(MP)from sturgeon under low salt condition,MP added with different concentrations of Arg was microwaved and evaluated for physicochemical,structural and morphological properties and intermolecular interactions after 1,3 and 5 min(<40℃).It was found that the solubility of MP decreased with increasing microwaving time and was improved by appropriate concentrations of Arg(P<0.05).The turbidity of MP microwaved for 5 min significantly decreased with increasing addition of Arg(P<0.05).The particle size decreased with increasing levels of Arg addition.In addition,Arg inhibited the formation of large protein clusters during microwave heating as shown by atomic force microscopy.In the control group,the contents of ionic and hydrogen bonds decreased significantly after microwave treatment for 3 min,while the contents of hydrophobic interaction and disulfide bond increased significantly(P<0.05).The addition of 40 mmol/L Arg inhibited the ionic bond and hydrophobic interaction and increased the hydrogen and disulfide bonds.The molecular dynamics simulation results showed that at 300 K,the root mean square deviation(RMSD)for myosin increased from about 0.52 to 5.85 nm after Arg binding to it,and the radius of gyration(Rg)also increased,indicating that Arg promoted the dissociation of MP aggregates under low salt condition,and the aggregate characteristics changed from larger protein clusters to smaller particles.Furthermore,binding of Arg to myosin decreased its structural tightness,resulting in more loose protein conformation.The findings of this study provide sufficient conditions for enhancing protein cross-linking in the gel strengthening stage.

关 键 词：微波 低盐 肌原纤维蛋白 精氨酸 解聚 原子力显微镜 分子动力学模拟 

分 类 号：S986.1[农业科学—捕捞与储运]