Evolution of amyloid fibril from lysozyme and subsequent encapsulation of curcumin

This study aimed to develop a lysozyme-derived amyloid fibril (Lys-F) with enhanced hydrophobicity using lysozyme (Lys) to achieve efficient encapsulation of curcumin (Cur) via hydrophobic interactions, and to investigate storage stability and in vitro inflammatory response of Cur encapsulated within Lys-F. The results showed that Lys-F exhibited strong hydrophobicity and structural stability. Fluorescence spectroscopy revealed that Lys-F interacted hydrophobically with Cur, resulting in fluorescence quenching, indicating that amyloid fibril promoted hydrophobic interaction. Quartz crystal microbalance with dissipation monitoring (QCM-D) showed that at adsorption saturation, Lys exhibited a Δf shift of approximately −16.2 Hz in 3000 s, while Lys-F showed a greater Δf shift of −28.4 Hz in just 1000 s, indicating that Lys-F has a higher affinity for Cur. For storage stability, the retention rate of Cur in Lys-F/Cur could reach 80 % compared to only 30 % in Lys/Cur under identical conditions, confirming the protective effect of the amyloid fibril structure. In vitro experiments showed that both Lys-F and Lys-F/Cur exhibited good cytocompatibility and low immunogenicity and did not induce cellular oxidative stress. This work provides new insights into the potential application of lysozyme-derived amyloid fibrils as functional materials for the protection and efficient encapsulation of hydrophobic compounds.