Zhang Jianyou, Zhou Wei, Xu Mingjiang, Fang Chunhua, Du Qiwei, Xu Xia, Lyu Fei, Ding Yuting, Liu Jianhua
College of Food Science and Technology, Zhejiang University of Technology, Hangzhou, PR China.
Key Laboratory of Marine Fishery Resources Exploitment and Utilization of Zhejiang Province, Hangzhou, PR China.
J Sci Food Agric. 2021 Nov;101(14):6117-6124. doi: 10.1002/jsfa.11268. Epub 2021 May 8.
Myosin (Ms) is abundant in fish meat, but it has limited application in the food industry because of its low solubility and thermal stability. Our previous reports found that these functional properties of Ms can be significantly improved after glycation with konjac oligo-glucomannan (KOG). However, the effects of phosphorylated KOG (PKOG) on physicochemical, structural and functional properties of silver carp Ms are still unknown.
This study characterized the silver carp Ms protein glycated with PKOG at 50 °C and 75% relative humidity for 48 h. As degree of phosphorylation increased, free amino content increased, whereas degree of grafting decreased. Meanwhile, isoelectric point (pI) reduced, however, PKOGs showed no differences in pI. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis suggested the formation of glycoconjugates, and scanning electron microscopy revealed thinner flakes and uneven appearance of glycoconjugates. Fourier transform infrared spectroscopy indicated that the amide I, II and III bands of Ms were changed by the glycation. Ms became highly soluble in 0.5 mol L NaCl with increased phosphate addition in PKOGs. Thermal stability of Ms was effectively improved when heated at 80 °C for 60 min.
Glycation with appropriate PKOG might be a promising method for Ms modification because of the resulting improvement in solubility and thermal stability. © 2021 Society of Chemical Industry.
肌球蛋白（Ms）在鱼肉中含量丰富，但由于其低溶解性和热稳定性，在食品工业中的应用有限。我们之前的报告发现，用魔芋低聚葡甘露聚糖（KOG）进行糖基化后，Ms的这些功能特性可得到显著改善。然而，磷酸化魔芋低聚葡甘露聚糖（PKOG）对鲤鱼Ms的物理化学、结构和功能特性的影响仍不清楚。
本研究对在50°C和75%相对湿度下用PKOG糖基化48小时的鲤鱼Ms蛋白进行了表征。随着磷酸化程度的增加，游离氨基含量增加，而接枝率降低。同时，等电点（pI）降低，不过，不同PKOG的pI没有差异。十二烷基硫酸钠-聚丙烯酰胺凝胶电泳分析表明形成了糖缀合物，扫描电子显微镜显示糖缀合物的薄片更薄且外观不均匀。傅里叶变换红外光谱表明，Ms的酰胺I、II和III带因糖基化而发生了变化。随着PKOG中磷酸盐添加量的增加，Ms在0.5 mol·L NaCl中变得高度可溶。在80°C加热60分钟时，Ms的热稳定性得到有效提高。
由于糖基化后溶解性和热稳定性得到改善，用合适的PKOG进行糖基化可能是一种很有前景的Ms修饰方法。© 2021化学工业协会。
