该研究采用缓冲液浸提法提取牛蒡根蛋白（Burdock Root Protein，BRP），并制备载泥鳅降压肽丙氨酸-组氨酸-亮氨酸-亮氨酸（Ala-His-Leu-Leu，AHLL）的牛蒡根蛋白纳米颗粒（Burdock Root Protein Nanoparticles Loaded with Loach Antihypertensive Peptide，BANPs）。BRP与AHLL通过自组装形成BANPs，采用扫描电镜、荧光与紫外-可见光光谱扫描、傅里叶红外光谱等对BANPs的结构和分子间相互作用进行表征，考察了不同温度、pH值对BANPs稳定性的影响。结果发现，pH值5.0时，BANPs粒径较小（231.47 nm），带负电荷（-19.10 mV），BRP分子通过静电相互作用和疏水相互作用与AHLL分子结合。随着BRP与AHLL质量浓度的增加，当BRP为8 mg/mL，AHLL为200 μg/mL时，BRP对AHLL的包封率提高到77.28%，载药量提高到23.90%。在60~100 ℃范围内，BANPs的温度稳定性较高，与游离AHLL相比降解率低至46.90%；在pH值4.0~8.0范围内BANPs的pH稳定性较高，与游离AHLL相比降解率低至33.16%。该研究表明，BRP纳米载体可以有效地保护AHLL免受pH值和热降解的影响，具有作为功能性食品中生物活性肽的纳米递送系统的潜力。

In this study, burdock root protein (BRP) was obtained by buffer extraction, and burdock root protein nanoparticles (BANPs) loaded with loach antihypertensive peptide (Alanine-Histidine-Leucine-Leucine, AHLL) were then prepared. BANPs were formed by BRP and AHLL via self-assembly. The structure and intermolecular interactions of BANPs were studied by scanning electron microscopy, fluorescence and UV-Vis spectroscopy, and Fourier transform infrared spectroscopy. The stability of BANPs under different temperatures and pHs was also investigated. The results showed that the BANPs had a smaller particle size (231.47 nm) and negative charge (-19.10 mV), and were formed through electrostatic and hydrophobic interactions between BRP and AHLL at pH 5. As the mass concentrations of BRP and AHLL increased, the AHLL encapsulation efficiency increased and drug loading content increased (to 77.28% and 23.90%, respectively when BRP=8 mg/mL and AHLL=200 μg/mL). The BANPs showed a high stability in the temperature range of 60~100 ℃ and pH range of 4.0~8.0. Compared to free AHLL, the degradation rate of encapsulated AHLL was as low as 33.16%. This study has shown that BRP nanocarriers can effectively protect AHLL against the impacts of pH and thermal degradation, thus have the potential as a nano-delivery system for bioactive peptides in functional foods.

江苏省创新支撑计划乡村产业振兴项目（FX202201）；江苏省农业自主创新基金项目（CX(19)2006）