School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang, Jiangsu, China; Institute of Food Physical Processing, Jiangsu University, 301 Xuefu Road, Zhenjiang, Jiangsu, China.
School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang, Jiangsu, China; Institute of Food Physical Processing, Jiangsu University, 301 Xuefu Road, Zhenjiang, Jiangsu, China; College of Grain Engineering, Food & Drug, Jiangsu Vocational College of Finance & Economics, 8 Meicheng East Road, Huaian, Jiangsu, China.
Ultrason Sonochem. 2023 Mar;94:106336. doi: 10.1016/j.ultsonch.2023.106336. Epub 2023 Feb 16.
Electrospinning nanofibers (NFs) made from natural proteins have drawn increasing attention recently. Rapeseed meal is a by-product that rich in protein but not fully utilized due to poor properties. Therefore, modification of rapeseed protein isolates (RPI) is necessary to expand applications. In this study, pH shift alone or ultrasonic-assisted pH shift treatment was adopted, the solubility of RPI, along with the conductivity and viscosity of the electrospinning solution were detected. Moreover, the microstructure and functional characteristics of the electrospinning NFs, as well as the antibacterial activity of clove essential oil loaded-NFs were investigated. The tested parameters were remarkably improved after different treatments compared with the control, and synergistic effects were observed, especially under alkaline conditions. Hence, pH + US showed the maximum value of solubility, conductivity, and viscosity, which was more than 7-fold, 3-fold, and almost 1-fold higher than the control respectively. Additionally, SEM and AFM images showed a finer and smoother surface of NFs after treatments, and the finest diameter of 216.7 nm was obtained after pH + US treatment in comparison with 450.0 nm in control. FTIR spectroscopy of NFs demonstrated spatial structure changes of RPI, and improved thermal stability and mechanical strength of NFs were achieved after different treatments. Furthermore, an inhibition zone with a diameter of 22.8 mm was observed from the composite NFs. This study indicated the effectiveness of ultrasonic-assisted pH shift treatment on the physicochemical properties improvement and functional enhancement of NFs made from RPI, as well as the potential antibacterial application of the composite NFs in the future.
静电纺丝纳米纤维（NFs）由天然蛋白质制成，最近受到越来越多的关注。菜籽饼是一种富含蛋白质的副产物，但由于其性能不佳，尚未得到充分利用。因此，需要对菜籽蛋白分离物（RPI）进行改性，以扩大其应用。在这项研究中，采用了单独的 pH 值变化或超声辅助的 pH 值变化处理，检测了 RPI 的溶解度以及静电纺丝溶液的电导率和粘度。此外，还研究了静电纺丝 NFs 的微观结构和功能特性，以及丁香精油负载-NFs 的抗菌活性。与对照相比，经过不同处理后，测试参数有了显著提高，并且观察到协同效应，特别是在碱性条件下。因此，pH+US 显示出最大的溶解度、电导率和粘度值，分别比对照提高了 7 倍、3 倍和近 1 倍。此外，SEM 和 AFM 图像显示处理后的 NFs 表面更细更光滑，与对照的 450.0nm 相比，pH+US 处理后获得的 NF 最细直径为 216.7nm。NFs 的傅里叶变换红外光谱表明 RPI 的空间结构发生了变化，并且经过不同处理后，NFs 的热稳定性和机械强度得到了提高。此外，复合 NFs 观察到直径为 22.8mm 的抑菌圈。这项研究表明，超声辅助 pH 值变化处理对 RPI 制成的 NFs 的物理化学性质的改善和功能的增强是有效的，并且复合 NFs 在未来具有潜在的抗菌应用。
