National Engineering Research Center for Nanomedicine, College of Life Science and Technology , Huazhong University of Science and Technology , Wuhan , Hubei 430074 , People's Republic of China.
Joint Laboratory for The Research of Modern Preparation Technology-Huazhong University of Science and Technology and Infinitus , Guangzhou , Guangdong 510663 , People's Republic of China.
J Agric Food Chem. 2019 Mar 27;67(12):3305-3312. doi: 10.1021/acs.jafc.8b05722. Epub 2019 Mar 13.
The peptide components of defatted walnut ( Juglans regia L.) meal hydrolysate (DWMH) remain unclear, hindering the investigation of biological mechanisms and exploitation of bioactive peptides. The present study aims to identify the peptide composition of DWMH, followed by to evaluate in vitro antioxidant effects of selected peptides and investigate mechanisms of antioxidative effect. First, more than 1 000 peptides were identified by de novo sequencing in DWMH. Subsequently, a scoring method was established to select promising bioactive peptides by structure based screening. Eight brand new peptides were selected due to their highest scores in two different batches of DWMH. All of them showed potent in vitro antioxidant effects on HO-injured nerve cells. Four of them even possessed significantly stronger effects than DWMH, making the selected bioactive peptides useful for further research as new bioactive entities. Two mechanisms of hydroxyl radical scavenging and ROS reduction were involved in their antioxidative effects at different degrees. The results showed peptides possessing similar capacity of hydroxyl radical scavenging or ROS reduction may have significantly different in vitro antioxidative effects. Therefore, comprehensive consideration of different antioxidative mechanisms were suggested in selecting antioxidative peptides from DWMH.
脱油核桃（Juglans regia L.）粕水解物（DWMH）的肽成分仍不清楚，这阻碍了对生物机制的研究和生物活性肽的开发。本研究旨在鉴定 DWMH 的肽组成，然后评估选定肽的体外抗氧化作用，并研究其抗氧化作用机制。首先，通过 DWMH 的从头测序鉴定出超过 1000 种肽。随后，建立了一种评分方法，通过基于结构的筛选选择有前途的生物活性肽。由于在两批 DWMH 中的得分最高，因此选择了 8 种全新的肽。它们都对 HO 损伤的神经细胞表现出强大的体外抗氧化作用。其中 4 种甚至比 DWMH 具有更强的作用，使所选的生物活性肽成为进一步研究的新生物活性实体。两种清除羟自由基和降低 ROS 的机制参与了它们在不同程度上的抗氧化作用。结果表明，具有相似清除羟自由基或降低 ROS 能力的肽可能具有显著不同的体外抗氧化作用。因此，建议在从 DWMH 中选择抗氧化肽时，综合考虑不同的抗氧化机制。
