Electrospun polylactic acid /poly (ε-caprolactone) fibrous encapsulated thymol/MIL-68(Al) as a food packaging material

Abstract

A controlled-release antibacterial active food packaging film was prepared from polylactic acid (PLA), poly (ε-caprolactone) (PCL), MIL-68(Al), and thymol (THY) by electrospinning. The performance, antioxidant activity and antibacterial activity of the MIL-68 (Al)/PLA/PCL nanofiber membrane loaded with THY were characterized, and the release behavior of THY from the nanofiber membrane was also explored. The addition of THY/MIL-68 (Al) could improve the water vapor barrier performance and UV resistance of the nanofiber membrane, while weakening the tensile strength and elongation at break. The load of MIL-68 (Al) could effectively improve the residence time of THY. Antioxidant experiments show that the nanofiber membrane inherits the antioxidative activity of THY, that only adding 4wt% of THY can improve the free radical scavenging ability, and that the quenching ability of DPPH free radicals can reach 50%. The in vitro antibacterial test showed that the nanofiber could effectively inhibit the growth of E. coli and S. aureus. The results indicated that THY/MIL-68 (Al)/PLA/PCL had a certain potential as a food active packaging, and MIL-68 (Al) had a strong controlled release ability for THY.

Keywords

• Thymol
• Polylactic acid
• Poly (ε-caprolactone)
• Electrospinning
• Release behavior
• Antibacterial activity