Servicio Extremeño de Salud, SES, Cáceres, Gobex, Spain.
IPROCAR Research Institute, TECAL Research Group, University of Extremadura, 10003 Cáceres, Spain.
Food Chem. 2018 Nov 30;267:111-118. doi: 10.1016/j.foodchem.2017.06.154. Epub 2017 Jun 30.
This study compared a hydroxyl radical-generating system (HRGS) (0.05-0.2mM Fe+0.6mM HO) and a glycation system (GLY) (0.05-0.2mM Fe+0.05M glucose) for their ability to promote protein carbonylation and tryptophan depletion in myofibrillar proteins, ovalbumin, β-lactoglobulin, soy protein and human serum albumin. Animal-source were more susceptible to protein carbonylation than soy proteins and globular were more susceptible than fibrillar proteins. Both systems promoted tryptophan loss and the formation of protein carbonyls and iron had a clear dose-effect in most systems and proteins. In the tested conditions, the GLY environment was more effective than the HRGS system in promoting the oxidative damage to food proteins. According to the results, glucose and HO may compete for iron for the production of glycosylative and oxidative species, respectively. This study provides original insight into the chemical mechanisms implicated in the oxidative and glycosylative damage to food proteins.
本研究比较了羟自由基生成系统（HRGS）（0.05-0.2mM Fe+0.6mM HO）和糖基化系统（GLY）（0.05-0.2mM Fe+0.05M 葡萄糖）在促进肌原纤维蛋白、卵清蛋白、β-乳球蛋白、大豆蛋白和人血清白蛋白的蛋白质羰基化和色氨酸耗竭方面的能力。动物来源的蛋白质比大豆蛋白更容易发生蛋白质羰基化，球状蛋白比纤维状蛋白更容易发生蛋白质羰基化。这两个系统都促进了色氨酸的损失和蛋白质羰基的形成，并且在大多数系统和蛋白质中，铁都有明显的剂量效应。在测试条件下，GLY 环境比 HRGS 系统更有效地促进了食物蛋白质的氧化损伤。根据这些结果，葡萄糖和 HO 可能分别与铁竞争，以产生糖基化和氧化物质。本研究为食物蛋白质的氧化和糖基化损伤所涉及的化学机制提供了新的见解。
