Self-assembled curcumin-soluble soybean polysaccharide nanoparticles: Physicochemical properties and in vitro anti-proliferation activity against cancer cells

Nanoencapsulation of lipophilic bioactive compounds in food biopolymers is important to functional beverages, but protein-based nanocapsules are unstable around the isoelectric point of protein. The objectives of this work were to study physicochemical properties of self-assembled curcumin-soluble soybean polysaccharide (SSPS) nanoparticles and evaluate the activities against proliferation of human colon HCT116 and mammary adenocarcinoma MCF-7 cancer cells before and after simulated digestions. Capsules with a hydrodynamic diameter of 200-300 nm and an encapsulation efficiency of ∼90% were self-assembled after increasing curcumin-SSPS mixture to pH 12.0 and lowering pH to 7.0. The capsule dispersions were stable at pH 2.0-7.0 and after heating at 95 °C for 1 min. No significant difference was observed for the viability of HCT 116 and MCF-7 cells challenged with 0.4, 4.0, and 40 μg/ml nanoencapsulated curcumin before and after simulated gastric and intestinal digestions. These findings may be significant to help develop functional beverages for disease prevention.