Wang Kangning, Ge Yuxin, Jia Yiyang, Hou Jiayi, Lu Fuping, Liu Yihan
Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, PR China.
Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, PR China.
Carbohydr Polym. 2025 Jun 1;357:123428. doi: 10.1016/j.carbpol.2025.123428. Epub 2025 Feb 21.
Starch is a primary energy source of human diet. Its physicochemical properties and digestibility can be improved by incorporating exogenous protein. In this study, mung bean protein isolate was covalently crosslinked using transglutaminase and proanthocyanidin to create crosslinked mung bean protein isolate. This modified protein was combined with corn starch to form crosslinked mung bean protein isolate-corn starch composite samples. Results demonstrated that these composite samples exhibited superior physicochemical properties, including reduced swelling capacity, enhanced freeze-thaw stability, improved thermostability, and enhanced antioxidant properties. During in vitro digestion, the improved corn starch digestibility was attributed to two factors: first, hydrogen bonding and electrostatic interactions between crosslinked mung bean protein isolate and corn starch; and second, the synergistic crosslinking of transglutaminase and proanthocyanidin promoting the formation of a stable protein network of mung bean protein isolate, serving as a physical barrier to protect corn starch. After co-treatment with transglutaminase and proanthocyanidin, significant changes of mung bean protein isolate occurred in their secondary and tertiary structures, enhancing its protein network strength, thereby improving the physicochemical properties of corn starch. These findings propose a new strategy for reducing rapidly digestible starch and provide a theoretical foundation for developing low glycemic index starch foods.
淀粉是人类饮食的主要能量来源。通过添加外源蛋白质可以改善其物理化学性质和消化率。在本研究中，使用转谷氨酰胺酶和原花青素对绿豆分离蛋白进行共价交联，制备交联绿豆分离蛋白。将这种改性蛋白与玉米淀粉结合，形成交联绿豆分离蛋白-玉米淀粉复合样品。结果表明，这些复合样品具有优异的物理化学性质，包括降低的溶胀能力、增强的冻融稳定性、改善的热稳定性和增强的抗氧化性能。在体外消化过程中，玉米淀粉消化率的提高归因于两个因素：第一，交联绿豆分离蛋白与玉米淀粉之间的氢键和静电相互作用；第二，转谷氨酰胺酶和原花青素的协同交联促进了绿豆分离蛋白稳定蛋白网络的形成，作为保护玉米淀粉的物理屏障。经转谷氨酰胺酶和原花青素共同处理后，绿豆分离蛋白的二级和三级结构发生了显著变化，增强了其蛋白网络强度，从而改善了玉米淀粉的物理化学性质。这些发现提出了一种降低快速消化淀粉的新策略，并为开发低血糖指数淀粉食品提供了理论基础。
