Characteristics and antioxidant activity of Elsholtzia splendens extract-loaded nanoparticles.

Elsholtzia splendens extract-loaded chitosan nanoparticles prepared by ionic gelation were characterized by particle size, zeta potential, entrapment efficiency, and loading efficiency. As the initial concentration of E. splendens extract was increased, the loading efficiency and zeta potential significantly increased, whereas the entrapment efficiency and particle size significantly decreased. The optimum concentration of E. splendens extract for maximum loading efficiency was found to be 0.8 mg/mL. Both free E. splendens extract and E. splendens extract-loaded chitosan nanoparticles showed concentration-dependent antioxidant activity. However, the lipid peroxidation inhibitory activity of E. splendens extract was effectively enhanced when it was entrapped within chitosan nanoparticles. Chitosan nanoparticle encapsulation is therefore a potentially valuable technique for improving the antioxidant activity of E. splendens extract.