Physicochemical properties and antibacterial activity of corn starch-based films incorporated with Zanthoxylum bungeanum essential oil

Abstract

Herein, corn starch-based films were prepared by casting method and different concentrations of Zanthoxylum bungeanum essential oil (ZYO) were added to evaluate the morphological, optical, mechanical, and barrier properties of the resultant films. Additionally, structural analysis was carried out via atomic force microscopy and the antibacterial activities against Staphylococcus aureus, Escherichia coli, and Listeria monocytogenes were assessed. We found that the elongation at break was significantly increased (P < 0.05), whereas tensile strength, moisture content, solubility in water, and water vapor permeability rate were significantly decreased (P < 0.05) in films incorporated with ZYO compared with oil-free films. Furthermore, incorporation of ZYO increased the opacity and decreased the gloss of films. Incorporation of ZYO appears to increase the surface roughness and the antibacterial activity of the films. In sum, ZYO can potentially be used in food packaging, particularly food intended to be protected from light and susceptible to spoilage by microorganisms.

Keywords: Antibacterial activity; Biodegradable films; Corn starch-based films; Mechanical properties; Zanthoxylum bungeanum essential oil.