Zein/gum Arabic nanoparticle-stabilized Pickering emulsion with thymol as an antibacterial delivery system

Zein/gum Arabic (GA) nanoparticles (ZGPs) were fabricated to stabilize the oil-water interface of a Pickering emulsion. The Pickering emulsion was successfully fabricated at an oil fraction of 0.3 with 6.25% concentration of ZGPs. The droplet size and creaming index of the Pickering emulsions were influenced significantly by the concentrations of the ZGPs and oil fractions. Morphological observations showed that droplet aggregation occurred when the concentrations of ZGPs decreased or the oil fraction increased. The interfacial tension and rheological properties of the Pickering emulsions indicated that the ZGPs formed a stable oil-water interfacial layer and limited agglomeration and Ostwald ripening. Thymol loaded ZGP-stabilized Pickering emulsion was able to significantly inhibit the growth of E. coli. In addition, the ZGP-stabilized Pickering emulsion with thymol exhibited a controlled-release effect of thymol and antibacterial activity due to the protective effect of the stable interfacial layer of the ZPGs.