Preparation and evaluation of novel Agriophyllum squarrosum starch nanoparticles for encapsulation of lycopene with enhanced retention rate and bioactivity during simulated in-vitro digestion

In this study, we developed novel Agriophyllum squarrosum starch nanoparticles (ASSNPs) for the encapsulation of lycopene (LYC), aiming to enhance its stability and bioactivity under adverse environmental and digestive conditions. The small-granule starch extracted from A. squarrosum seeds was processed using ionic liquids (ILs) as an effective “green” solvent, followed by a systematic treatment involving ultrasonication and pullulanase to prepare the ASSNPs. The resulting nanoparticles exhibited small size, narrow particle size distribution, negative zeta potential, and high encapsulation efficiency of up to 64.3 %. The structures of ASSNPs were characterized using Fourier transform infrared spectroscopy, X-ray diffraction, differential scanning calorimetry, scanning electron microscopy, and transmission electron microscopy. These analytical techniques confirmed the successful encapsulation of LYC and revealed increased intermolecular interactions. Stability and degradation experiments demonstrated that the retention of the LYC in the complexes was significantly higher than that of the unencapsulated LYC, highlighting the superior protective effects of ASSNPs on the storage and digestive stability of LYC. This research elucidated the structural features of the complex between ASSNPs and LYC, underscoring the potential of ASSNPs as a food-grade delivery system. This approach offers a sustainable method for enhancing the bioavailability of hydrophobic nutraceuticals.