Food–medicine homology nanostructures: self-assembly, sustained release, and extended anti-inflammatory effects of Eucommia ulmoides nanoparticles

Plant-derived self-assembled nanoparticles, especially from food-medicine homology sources, are gaining attention, yet their structure-function relationships remain unclear. This study identified such nanoparticles from leaf decoction of Eucommia ulmoides, a key plant in traditional Asian medicine and diet, termed EUPs. These spherical particles (~287.8 nm) were primarily composed of polysaccharides and polyphenols, with 268 polyphenolic compounds detected via UPLC-QTOF-MS. Stepwise dissociation-ultrafiltration and spectroscopic analyses revealed that polyphenols were bound to the polysaccharide through noncovalent interactions, including hydrogen bonding and hydrophobic forces, forming a layered structure with sustained-release and thermo-responsive properties. Compared with free polyphenols, EUPs exhibited significantly prolonged anti-inflammatory effects in LPS-stimulated RAW 264.7 macrophages, reflected by the suppression of key inflammatory cytokines, including TNF-α, IL-6 and NO. Therefore, it aims to offer mechanistic insights into the multi-component synergistic anti-inflammatory effects of E. ulmoides and supporting the material basis of food-medicine homology.