National Engineering Research Center of Seafood, School of Food Science and Technology , Dalian Polytechnic University , Dalian , Liaoning 116034 , People's Republic of China.
College of Agriculture , Liaocheng University , Liaocheng , Shandong 252000 , People's Republic of China.
J Agric Food Chem. 2019 Apr 3;67(13):3796-3810. doi: 10.1021/acs.jafc.9b00760. Epub 2019 Mar 22.
In this study, Alg-Gly-Ala-Val-Leu-His (RGAVLH) obtained from pine nut ( Pinus koraiensis Sieb. et Zucc.) protein was chosen to investigate the phenomenon of immunomodulatory activity improvement upon pulsed electric field (PEF) processing. The influence of electric field intensity on immunomodulatory activity of RGAVLH was evaluated using RAW 264.7 cells. It was found that RGAVLH can not only significantly ( p < 0.05) improve the capability of macrophage phagocytosis but also promote the production of nitric oxide. RGAVLH treated under an electric field intensity of 40 kV/cm exhibited the best immunomodulatory activity. The primary and secondary structures of PEF-treated peptides were analyzed by mid-infrared (MIR) spectroscopy, Raman spectroscopy, circular dichroism spectroscopy, and one-dimensional/two-dimensional nuclear magnetic resonance spectroscopy. After PEF treatment, the primary structure of RGAVLH was not influenced, as evaluated by MIR and Raman spectra. In addition, the content of β-sheet was decreased and active hydrogen was changed in PEF-treated RGAVLH solution. Moreover, the long-range connectivity between CH (3.39 ppm) and NH (8.24 ppm) was enhanced by PEF. Therefore, the improvement of the immunomodulatory activity of RGAVLH might result from the changes of the spatial state and spatial force in the peptide solution system.
在这项研究中，选择来自松仁（红松 Pinus koraiensis Sieb. et Zucc.）蛋白的 Alg-Gly-Ala-Val-Leu-His（RGAVLH）来研究脉冲电场（PEF）处理对免疫调节活性改善的现象。使用 RAW 264.7 细胞评估电场强度对 RGAVLH 免疫调节活性的影响。结果表明，RGAVLH 不仅可以显著（p<0.05）提高巨噬细胞吞噬能力，还可以促进一氧化氮的产生。在 40 kV/cm 的电场强度下处理的 RGAVLH 表现出最佳的免疫调节活性。通过中红外（MIR）光谱、拉曼光谱、圆二色性光谱和一维/二维核磁共振光谱分析 PEF 处理肽的一级和二级结构。PEF 处理后，通过 MIR 和拉曼光谱评估，RGAVLH 的一级结构不受影响。此外，PEF 处理 RGAVLH 溶液中β-折叠含量减少，活性氢发生变化。而且，通过 PEF 增强了 CH（3.39 ppm）和 NH（8.24 ppm）之间的远程连接。因此，RGAVLH 免疫调节活性的提高可能是由于肽溶液体系中空间状态和空间力的变化所致。
