Development of multifunctional bioactive food packaging based on silver nanoparticles/grape fruit peel extract reinforced PVA composites

Abstract

Active food packaging based on bio-wastes has gained considerable attention these days due to their ecofriendly and biodegradable behavior. In this study, multifunctional bio-composite films with remarkable anti-oxidant and anti-microbial attributes were synthesized by incorporating biosynthesized silver nanoparticles (AgNPs) and grape fruit peel extract (GFPE) into polyvinyl alcohol (PVA) matrix. Synthesized films were characterized in terms of Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Scanning electron microscopy (SEM), Differential scanning calorimetry (DSC) and Dynamic Mechanical Analyzer (DMA). Antioxidant activity of AgNPs-GFPE/PVA films was determined by %DPPH scavenging ability and Ferric reducing antioxidant power assay while antimicrobial activity was measured by agar diffusion method. XRD analysis revealed the semi-crystalline behavior of synthesized composites with characteristics peak at 38° whereas SEM micrographs confirmed the homogeneous dispersion of reinforcement and porous rough surface structure of AgNPs-GFPE/PVA nano-composites. AgNPs-GFPE/PVA nanocomposite exhibited glass transition temperature (Tg) at ∼116 °C and Tm ∼191 °C along with the storage modulus of 685 MPa, revealing significantly enhanced thermal and mechanical stability of composites compared to pure PVA films. The composite films exhibited remarkable antioxidant potential i.e DPPH scavenging activity ∼50 % and reducing power ∼ 0.58. The AgNPs-GFPE/PVA nano-composite films exhibited remarkable antimicrobial activity in response to food borne pathogens. The results designated that the synthesized composite films have prodigious potential of being cheap, eco-friendlier substitute to conventional materials for application in food packaging, which certify the safety and economical life span of packed food.