Investigation of Antimicrobial Effect and Mechanical Properties of Modified Starch Films, Cellulose Nanofibers, and Citrus Essential Oils by Disk Diffusion Method

This research investigated the mechanical and thermal properties of starch films reinforced with cellulose Nanofibers and lemon essence, which are used in the food packaging industry. One of the aims of this study is to examine the effect of each parameter (alone and together) and evaluate the amount of starch, cellulose Nanofibers, and lemon essence in the manufacture of films. Furthermore, finding a relation between the different amount of used materials that provides the best properties is another research goal. Biodegradable nanocomposite films based on starch and cellulose nanofibers reinforcing agents were prepared via solvent casting. The physical properties of as-prepared starch and cellulose Nano fibers films, such as thickness, colour, and structure, were studied by XRD and scanning electron microscope (SEM). Moreover, DSC and infrared spectroscopy (FT-IR) were used to investigate their thermal properties, such as glass transition temperature (Tg), melting temperature, and crystallization percentage. The disk diffusion method evaluated the antimicrobial effect of biodegradable films containing different concentrations of essence against Escherichia coli and Staphylococcus aureus bacteria. SEM images show uniform and better dispersion of starch and cellulose Nano fibers containing lemon essence, especially in starch and cellulose Nanofibers on the surface (SNE-4).