Enhancing stability and <i>in vitro</i> bioaccessibility of vitamin D3 via soluble soybean polysaccharide-based nanoparticles mediated by nisin

Abstract Bone health, neuromuscular function, and metabolic balance are all significantly impacted by vitamin D-3 (VD-3). However, modern people have reduced outdoor activities, insufficient skin exposure to sunlight, and the destruction of VD3 in food by gastric acid, leading to a global deficiency in VD3. Therefore, this study aims to improve the stability and bio-accessibility of VD3 by constructing nanoparticles based on soluble soybean polysaccharides and nisin (Nisin-SSPS-NPs). By optimizing the preparation conditions, when pH 4.0 is reached, the mass ratio of SSPS to Nisin is 3:1, and VD3 concentration is 0.12 mg/mL, the prepared nanoparticles have a particle size of 521.13 nm and PDI of 0.221, achieving a high encapsulation efficiency of 88.2 %. The results of lighting and thermal stability experiments and in vitro digestion assays showed that Nisin-SSPS-NPs can effectively protect VD3, avoid the degradation of VD3 during lighting and heat treatment, as well as in vitro digestion, thereby improving the stability and bio-accessibility of VD3.