Liu Hongyan, Zhang Xinyu, Hou Ruyan, Chen Guijie, Fang Yajing, Zhang Jiachao, Liu Lingyi, Liu Lianliang
State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Key Laboratory of Animal Protein Deep Processing Technology of Zhejiang, School of Food and Pharmaceutical Sciences, Ningbo University, Ningbo, Zhejiang, China.
State Key Laboratory of Tea Plant Biology and Utilization, Key Laboratory of Food Nutrition and Safety, School of Tea and Food Science & Technology, Anhui Provincial Joint Construction Key Laboratory of Food Safety Monitoring and Quality Control, Anhui Agricultural University, Hefei 230036, China.
Int J Biol Macromol. 2025 Jan;287:138442. doi: 10.1016/j.ijbiomac.2024.138442. Epub 2024 Dec 5.
Protein modification can improve the bioavailability of polyphenols, while polyphenols can also improve the functional properties of pea protein. Four representative polyphenols (gallic acid, ferulic acid, catechin and kaempferol) were covalently combined with pea protein by ultrasonic assisted grafting (free radical grafting, laccase method and alkali treatment), and the structure and functional properties of the conjugated compounds were characterized. The interaction was evaluated by surface hydrophobicity, free sulfhydryl content determination and SDS-PAGE. Fluorescence spectra and Fourier transform infrared spectra revealed that polyphenol binding reduced the α-helix content of pea protein and changed its structure. In addition, the antioxidant activity of the conjugate was significantly improved compared to natural pea protein (DPPHby 7.5 to 20.2 times, ABTSby 2.8 to 4.3 times, FRAP by 1.4 to 4.1 times). At the same time, the introduction of polyphenols also optimized the thermal stability of pea protein, and increased the denaturation temperature of pea protein (113.1 °C) by 0.19-6.63 °C. The emulsifying properties were also enhanced by covalent modification, and the emulsifying properties of the ultrasound-assisted conjugates were better. In summary, the pea protein-polyphenol conjugate provides a new solution for improving the bioavailability of polyphenols and preparing polyphenol delivery systems for complex emulsions.
蛋白质修饰可以提高多酚的生物利用度，而多酚也可以改善豌豆蛋白的功能特性。通过超声辅助接枝（自由基接枝、漆酶法和碱处理）将四种代表性多酚（没食子酸、阿魏酸、儿茶素和山奈酚）与豌豆蛋白共价结合，并对共轭化合物的结构和功能特性进行了表征。通过表面疏水性、游离巯基含量测定和SDS-PAGE对相互作用进行了评估。荧光光谱和傅里叶变换红外光谱表明，多酚结合降低了豌豆蛋白的α-螺旋含量并改变了其结构。此外，与天然豌豆蛋白相比，共轭物的抗氧化活性显著提高（DPPH提高7.5至20.2倍，ABTS提高2.8至4.3倍，FRAP提高1.4至4.1倍）。同时，多酚的引入还优化了豌豆蛋白的热稳定性，并使豌豆蛋白的变性温度（113.1℃）提高了0.19-6.63℃。共价修饰也增强了乳化性能，超声辅助共轭物的乳化性能更好。总之，豌豆蛋白-多酚共轭物为提高多酚的生物利用度和制备用于复合乳液的多酚递送系统提供了一种新的解决方案。
