Huang Zhilian, Li Tingting, Wang Jing, Fan Mingcong, Li Yan, Qian Haifeng, Wang Li
State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122, China.
Department of Food Science and Engineering, College of Light Industry and Food Engineering, Nanjing Forestry University, Jiangsu Province, 210037, China.
Food Funct. 2025 Jul 1;16(13):5475-5492. doi: 10.1039/d5fo00758e.
The integration of plant proteins with bioactive compounds offers a promising strategy to enhance their environmental stability. This study investigated the complexation of mung bean protein (MBP) with epigallocatechin gallate (EGCG) and the impact of affinity differences resulting from structural variations of MBP on the performance of the resulting complexes. MBP fractions obtained ammonium sulfate precipitation displayed distinct protein compositions, especially MBP-60%S, which was mainly 8S vicilin. MBPs and EGCG rely on hydrogen bonding and hydrophobic interactions for spontaneous self-assembly, with hydrogen bonding dominating in highly soluble MBP. EGCG binding induced structural changes in MBPs, including an increase in α-helix content and size, as well as a reduction in β-sheet content and solubility. Notably, MBP-60%S exhibited the strongest affinity for EGCG. These conformational shifts enhanced the thermal stability of EGCG, thereby mitigating the loss of antioxidant capacity due to its thermal degradation. Moreover, the bioaccessibility of EGCG was increased by 1.91-3.22-fold. However, MBP-60%SE showed resistance to gastric digestion, likely due to the altered protein structure and interaction strength. Overall, these findings provide valuable insights into the functionalization of plant proteins, offering a foundation for the development of high-quality functional foods and novel applications of mung bean protein.
植物蛋白与生物活性化合物的结合为提高其环境稳定性提供了一种有前景的策略。本研究考察了绿豆蛋白（MBP）与表没食子儿茶素没食子酸酯（EGCG）的络合作用，以及MBP结构变异导致的亲和力差异对所得络合物性能的影响。通过硫酸铵沉淀获得的MBP组分具有不同的蛋白质组成，尤其是MBP-60%S，其主要为8S球蛋白。MBP和EGCG依靠氢键和疏水相互作用进行自发自组装，在高溶解性的MBP中氢键起主导作用。EGCG的结合引起了MBP的结构变化，包括α-螺旋含量和尺寸增加，以及β-折叠含量和溶解度降低。值得注意的是，MBP-60%S对EGCG表现出最强的亲和力。这些构象变化增强了EGCG的热稳定性，从而减轻了由于其热降解导致的抗氧化能力损失。此外，EGCG的生物可及性提高了1.91-3.22倍。然而，MBP-60%SE对胃消化具有抗性，这可能是由于蛋白质结构和相互作用强度的改变。总体而言，这些发现为植物蛋白的功能化提供了有价值的见解，为开发高品质功能性食品和绿豆蛋白的新应用奠定了基础。
