Bolea Carmen Alina, Grigore-Gurgu Leontina, Aprodu Iuliana, Vizireanu Camelia, Stănciuc Nicoleta
Dunărea de Jos University of Galati, Faculty of Food Science and Engineering, Domnească Street 111, 800201 Galati, Romania.
Foods. 2019 Apr 18;8(4):131. doi: 10.3390/foods8040131.
The aim of this work was to advance knowledge on the potential use of black rice different sieving fractions for various functional applications, through proximate analysis, thermal degradation kinetics of phytochemical and characterization of the thermal behavior of the main proteins, from the perspectives of their use as a food ingredient. The results indicated that the thermal degradation of phytochemicals followed a first-order reaction kinetics for all the tested fractions. The temperature-dependent degradation was adequately modeled according to the Arrhenius equation. The calculated activation energies () and values were different among the four studied parameters. The kinetic parameters depended on the grinding and sieving degree, the anthocyanins being the most thermolabile compounds, thus affecting the antioxidant activity. Three protein fractions were identified by electrophoresis with different molecular weight, such as albumin, globulin, and glutelin. The fluorescence spectroscopy experiments revealed the sequential character of the heat-induced conformational changes, different molecular events being suggested, such as folding in the lower temperature range and unfolding at higher temperature. The significance of the study is evidenced by the need to identify and advance the process-structure-function relationships for various biologically active compounds from the perspective of obtaining food or ingredients nutritionally optimized.
这项工作的目的是，从将黑米不同筛分部分用作食品成分的角度出发，通过近似分析、植物化学物质的热降解动力学以及主要蛋白质热行为的表征，增进对其在各种功能应用中潜在用途的了解。结果表明，所有测试部分的植物化学物质的热降解均遵循一级反应动力学。根据阿伦尼乌斯方程对温度依赖性降解进行了充分建模。在所研究的四个参数中，计算出的活化能（）和值各不相同。动力学参数取决于研磨和筛分程度，花青素是最不耐热的化合物，从而影响抗氧化活性。通过电泳鉴定出三种分子量不同的蛋白质部分，如白蛋白、球蛋白和谷蛋白。荧光光谱实验揭示了热诱导构象变化的顺序特征，表明了不同的分子事件，如在较低温度范围内折叠和在较高温度下展开。从获得营养优化的食品或成分的角度来看，识别和推进各种生物活性化合物的过程 - 结构 - 功能关系的必要性证明了该研究的重要性。
