Ecofriendly Active Poly(vinyl alcohol)/Agarose/D-glucose/Piper Betle Linn. Leaf Extract Films as Potential Packaging Materials

Abstract

The present study aimed at developing ecofriendly active films from poly(vinyl alcohol) (PVA), agarose, D-glucose and Piper betle Linn. leaf extract (PBLLE) using a solution casting method. Agarose, D-glucose and PBLLE have been found to exhibit excellent compatibility with the PVA-matrix and thus support desired changes in the film characteristics. The co-addition of agarose and D-glucose to PVA gave rise to water-resistance as well as flexibility of the PVA-based films. The incorporation of PBLLE imparted active functions to the PVA/agarose/D-glucose film, such as the ability to scavenge DPPH radicals and strong antibacterial activity against both Gram-negative and Gram-positive bacteria. Moreover, significant improvement in both mechanical strength and flexibility of the PVA/agarose/D-glucose films was obtained upon the addition of a sufficient amount of PBLLE. A PBLLE/PVA ratio of 1.5 was found to promote a more than 1.5-fold increase of the elongation at break. Increasing PBLLE content in the films enhanced the UV absorption in the 300-450 nm range. Characterization results show that the PVA/agarose/D-glucose/PBLLE films possess interesting properties for UV-protective and active packaging applications.