Co-encapsulation of α-tocopherol and resveratrol within zein nanoparticles: Impact on antioxidant activity and stability

Simultaneous administration of multiple bioactive components might produce synergistic effect and offer multiple health benefits. This provides motivation to develop co-delivery system that can simultaneously encapsulate a plurality of bioactive components. In this study, α-tocopherol and resveratrol with different solubility were successfully encapsulated into zein nanoparticles. Encapsulation efficiency of α-tocopherol and resveratrol reached 96% and 67%, respectively. Size and ζ-potential of zein particles varied from 80 to 122 nm and +27 to +60 mV, respectively. Resveratrol was encapsulated at the portion between the hydrophobic core and the surface of zein particles. About 47% of α-tocopherol and 80% of resveratrol were found in the zein particles when stored at 45 °C for up to 84 days. α-Tocopherol- and resveratrol-loaded zein particles provided a better protective effect on α-tocopherol than did α-tocopherol-loaded zein particles and eliminated negative effect of α-tocopherol on the stability of resveratrol. These results might be useful for the design of a delivery system for the co-encapsulation of several nutrients with different solubilities.