Li Na, Arunkumar Abhiram, Etzel Mark R
Department of Food Science, University of Wisconsin, 1605 Linden Drive, Madison, WI 53706, USA.
Voyager Therapeutics, 75 Sidney St., Cambridge, MA 02139, USA.
Foods. 2019 Oct 25;8(11):528. doi: 10.3390/foods8110528.
Glycation of proteins by polysaccharides via the Maillard reaction improves the functional properties of proteins in foods, such as solubility, heat stability, emulsification, foaming, and gelation. Glycation is achieved by either the dry heating or the wet heating method, and considerable research has been reported on the functionality of the reaction mixture as tested in foods. While the characteristics of the glycates in foods have been well studied, the kinetics and equilibrium yield of the protein-polysaccharide glycation reaction has received little attention. Industrial manufacture of the glycates will require understanding the kinetics and yield of the glycation reaction. This work examined the glycation of whey protein isolate (WPI) and glycomacropeptide (GMP) by using dextran and the dry-heating method at 70 °C and 80% relative humidity. The disappearance of un-glycated protein and the creation of glycated protein were observed using chromatographic analysis and fluorescence laser densitometry of sodium dodecyl sulfate-polyacrylamide gels. Data were fit using a first-order reversible kinetic model. The rate constants measured for the disappearance of un-glycated protein by sodium dodecyl sulfate-polyacrylamide (SDS-PAGE) (k = 0.33 h) and by chromatographic analysis (k = 0.38 h) were not statistically different from each other for WPI-dextran glycation. Dextran glycation of GMP was slower than for WPI (k = 0.13 h). The slower rate of glycation of GMP was attributed to the 50% lower Lys content of GMP compared to WPI. Yield for the dry-heating dextran glycation method was 89% for WPI and 87% for GMP. The present work is useful to the food industry to expand the use of glycated proteins in creating new food products.
多糖通过美拉德反应使蛋白质糖基化，可改善食品中蛋白质的功能特性，如溶解性、热稳定性、乳化性、起泡性和凝胶化。糖基化可通过干热法或湿热法实现，并且已有大量关于食品中反应混合物功能的研究报道。虽然食品中糖基化产物的特性已得到充分研究，但蛋白质 - 多糖糖基化反应的动力学和平衡产率却很少受到关注。糖基化产物的工业化生产需要了解糖基化反应的动力学和产率。本研究采用葡聚糖和干热法，在70°C和80%相对湿度条件下，考察了乳清分离蛋白（WPI）和糖巨肽（GMP）的糖基化反应。使用十二烷基硫酸钠 - 聚丙烯酰胺凝胶的色谱分析和荧光激光密度测定法，观察未糖基化蛋白质的消失和糖基化蛋白质的生成。数据采用一级可逆动力学模型拟合。对于WPI - 葡聚糖糖基化反应，通过十二烷基硫酸钠 - 聚丙烯酰胺凝胶电泳（SDS - PAGE）（k = 0.33 h）和色谱分析（k = 0.38 h）测得的未糖基化蛋白质消失的速率常数在统计学上无显著差异。GMP的葡聚糖糖基化反应比WPI慢（k = 0.13 h）。GMP糖基化反应速率较慢归因于其赖氨酸含量比WPI低50%。干热葡聚糖糖基化法的产率对于WPI为89%，对于GMP为87%。本研究对食品工业在开发新食品时扩大糖基化蛋白质的应用具有指导意义。
