Chitosan and polyvinyl alcohol nanocomposites with cellulose nanofibers from ginger rhizomes and its antimicrobial activities

The agro-industrial waste obtained after the isolation of bio-constituents from ginger is available in abundance. In the present study, the effective isolation of ginger nanofibers (GNF) was carried out by acid hydrolysis and high pressure homogenization to get cellulose nanofibers with 100 to 200 nm width. Bionanocomposites were also prepared by reinforcing different ratios of (1% to 7%) GNF with chitosan (CS) and polyvinyl alcohol (PVA) matrices by solvent cast method and the 5% GNF with CS and PVA resulted a high mechanical strength composites than others. The surface morphology and structural analysis of the composites were identified by Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), Differential scanning calorimetry (DSC) and X-ray diffraction (XRD) methods. The inhibitory effect of 5% GNF bionanocomposites against Bacillus cereus, Escherichia coli, Staphylococcus aureus and Salmonella typhimurium indicated good antibacterial activity of the nanocomposites due to the addition of GNF in the biopolymer matrices. The use of GNF will help to increase the economic values of agricultural waste and the characteristic properties of GNF derived bionanocomposites could be possibly used in medical and packaging areas. (C) 2019 Elsevier B.V. All rights reserved.