Preparation of antibacterial poly(lactide)/poly(butylene adipate-co-terephthalate) composite films incorporated with grapefruit seed extract

Antimicrobial poly(lactide) (PLA)/poly(butylene adipate-co-terephthalate) (PBAT) blend films incorporated with grapefruit seed extract (GSE) were prepared using a solvent casting method. Effect of GSE on the morphological, water vapor barrier, thermostability, color, optical, and antimicrobial properties of PLA/PBAT composite films was investigated. The composite films showed a yellowish tint after incorporation of GSE and exhibited a high UV-light barrier property. Incorporation of GSE increased the flexibility and tensile strength of the composite films. Films incorporated with 7 wt% of GSE exhibited potent antibacterial activity against Listeria monocytogenes, but they showed only bacteriostatic activity against Escherichia coli. The PLA/PBAT-GSE composite film with UV-light barrier and antibacterial properties has a high potential for an active food packaging application.