A multifunctional film with insect-repellent and antimicrobial activities was developed. Star anise (Illicium verum Hook. f.) oil (SO) proved to be effective in repelling Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae) larvae and was selected as an insect-repellent agent. Thymol, a compound that demonstrated strong growth inhibition activities against both Staphylococcus aureus and Penicillium roqueforti, was selected as an antimicrobial agent. Based on the release profile test of SO using various plastic films, polypropylene (30 µm; PP 30) and low-density polyethylene (20 µm; LDPE 20) were selected as laminated films for sustainable insect-repellent and strong antimicrobial effects, respectively. Further, polyethylene terephthalate (12 µm; PET 12) was selected as an intermediate barrier layer. Finally, structure of the multilayer film was designed as PP 30/SO/PET 12/thymol/LDPE 20. The developed film demonstrated insect-repellent activity for >3 weeks, antibacterial activity for >2 weeks, and antifungal activity for 1 week. The results indicated that the developed multilayer film structure possessed strong, sustained insect-repellent and antimicrobial effects, providing a new possibility for the industrial applications to food packaging.Practical Application: A multifunctional active packaging film with insect-repellent and antimicrobial activities was developed. Star anise oil and thymol that showed insect-repellent and antimicrobial activities (antibacterial and antifungal activities), respectively, were added in coating layers in the multilayer film structure. The developed multilayer film proved an efficient insect-repellent activity against Plodia interpunctella for >3 weeks. Also, strong antibacterial and antifungal activities of the developed multilayer film were proved against Staphylococcus aureus and Penicillium roqueforti, respectively. The developed film has a potential for the industrial use to the food packaging material.Additional supporting information may be found online in the Supporting Information section at the end of the article. Figure S1. Schematic diagram of the repellency test trap.

A multilayer film containing star anise essential oil and thymol coating layers (SAEO and TH, respectively), with insect repellent and antimicrobial properties, has been developed using bar coating and adhesive lamination processes. Our previous study reported the in vitro activities of this polypropylene film (PP)/SAEO/polyethylene terephthalate film (PET)/TH/low‐density polyethylene film (LDPE) multilayer film. The current study focused on demonstrating the morphological, optical, and mechanical properties of the film, and evaluating its in vivo activities when used as a bread packaging material. The developed film was 15.03% thicker and 1.86% less transparent than the control film (without active agent coating layers: PP/PET/LDPE). While the color values of the developed film were slightly different from the control film, both films appeared similar to the naked eye. The tensile strength in the developed film was somewhat lower than that of the control film, while both films had statistically comparable values for elongation at break. During storage of sliced bread packaged in the developed film, the film both deterred insects from approaching toward and impeded the growth of microorganisms in the bread. These results suggest the potential applicability of the developed film as an active food packaging material with insect repellent and antimicrobial activities. Practical Application A multilayer film incorporated with insect repellent and antimicrobial coating layers was applied in sliced wheat bread packaging. The developed film effectively inhibited approaches of stored‐product insects to packaged bread and growth of microorganisms on the bread surface. It can be used as an active food packaging material that improves the safety and shelf‐life of foods.

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