Zhou Yichen, Zhang Rijun, Wang Junyong, Tong Yucui, Zhang Jing, Li Zhenzhen, Zhang Haosen, Abbas Zaheer, Si Dayong, Wei Xubiao
Laboratory of Feed Biotechnology, State Key Laboratory of Animal Nutrition and Feeding, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China.
Antioxidants (Basel). 2024 Jul 16;13(7):854. doi: 10.3390/antiox13070854.
Recent evidence suggests that mulberry leaves have good antioxidant activity. However, what the antioxidant ingredient is and how the ingredient works are still not well understood. In this study, we enzymatically hydrolyze mulberry leaf proteins (MLPs) using neutral protease and find that the mulberry leaf protein hydrolysates (MLPHs) have stronger antioxidant activity compared to MLPs. We separate the core antioxidant components in MLPHs by ion-exchange columns and molecular sieves and identify 798 antioxidant peptides by LC-MS/MS. Through bioinformatics analysis and biochemical assays, we screen two previously unreported peptides, P6 and P7, with excellent antioxidant activities. P6 and P7 not only significantly reduce ROS in cells but also improve the activities of the antioxidant enzymes SOD and CAT. In addition, both peptides are found to exert protective effects against HO-induced chromatin damage and cell apoptosis. Collectively, these results provide support for the application of mulberry leaf peptides as antioxidants in the medical, food and livestock industries.
最近的证据表明，桑叶具有良好的抗氧化活性。然而，抗氧化成分是什么以及该成分如何发挥作用仍未得到充分了解。在本研究中，我们使用中性蛋白酶对桑叶蛋白（MLP）进行酶解，发现桑叶蛋白水解物（MLPH）比MLP具有更强的抗氧化活性。我们通过离子交换柱和分子筛分离MLPH中的核心抗氧化成分，并通过LC-MS/MS鉴定出798种抗氧化肽。通过生物信息学分析和生化测定，我们筛选出两种以前未报道的具有优异抗氧化活性的肽，P6和P7。P6和P7不仅能显著降低细胞中的活性氧（ROS），还能提高抗氧化酶超氧化物歧化酶（SOD）和过氧化氢酶（CAT）的活性。此外，发现这两种肽对羟基自由基（HO）诱导的染色质损伤和细胞凋亡均具有保护作用。总的来说，这些结果为桑叶肽作为抗氧化剂在医药、食品和畜牧业中的应用提供了支持。
