Antioxidant Properties and Environmental Stability of Curcumin-Loaded Zein-Tea Saponin Nanoparticles

The curcumin-loaded zein-tea saponin (Zein-TS-Cur) nanoparticles were prepared using the antisolvent co-precipitation method, and the encapsulation efficiency, loading capacity, fluorescence intensity, particle size, PDI, Zeta-potential, antioxidant properties, and storage stability of the composite nanoparticles were determined to screened for the optimal preparation ratio,and to investigate their environmental stability. It was found that compared with individual zein nanoparticles, the nanoparticles prepared at the ratio of zein to tea saponin (TS) of 1:2 had the highest encapsulation efficiency of 96.02%, stronger fluorescence intensity of 4663, higher DPPH radical scavenging activity of 94.14%, and greater total antioxidant activity of 40.33%. The nanoparticles remained stable during storage, as well as under different pH, ionic strength, and temperature conditions, indicating that the nanoparticles were less affected by environmental conditions. It was shown that the nanoparticles with the addition of TS had better stability, which significantly improved the encapsulation efficiency, stability under different environmental conditions and antioxidant activity of the curcumin (Cur)-loaded nanoparticles. The results of this study are useful in providing guidance for the construction of efficient and stable delivery systems to improve the application of hydrophobic bioactives such as curcumin in pharmaceutical, food, and other industrial fields.