Self-assembled soy protein nanoparticles by partial enzymatic hydrolysis for pH-Driven Encapsulation and Delivery of Hydrophobic Cargo Curcumin

Abstract

Controlled partial enzymatic hydrolysis has been shown to be an efficacious strategy for devising and construction of multifunctional soy protein nanoparticles (SPNPs). In this work, we reported a successful fabrication of novel SPNPs obtained from self-assembly of the amphiphilic hydrolysate after partial hydrolysis of soy protein isolate (DH, 4%), and explored their potential as a nanocarrier for active cargo delivery. Curcumin was effectively loaded into the hydrophobic core of SPNPs by utilizing the pH-driven method, and the resultant curcumin-loaded SPNPs were spherical with a small particle size (80 nm in diameter), homogeneous size distribution and relatively high encapsulation efficiency (78%). The solubility and stability of curcumin against different NaCl concentrations (0–300 mM) and temperatures (75–95 °C) were remarkably enhanced by encapsulation into SPNPs. Additionally, SPNPs were able to effectively protect curcumin from degradation or precipitation during simulated gastric-intestinal digestion, showing a significantly enhanced bioaccessibility. Encapsulated curcumin was valid in alleviating cell oxidative damage induced by H2O2, mainly by scavenging intracellular free radicals, inhibiting lipid oxidation, and elevating endogenous antioxidant enzymes levels. Interestingly, the vehicle SPNPs showed synergistic antioxidant effect, creatively evidencing their bifunctionality in cellular antioxidant activity.