Physical Properties and Antibacterial Activity of Chitosan/Carboxymethyl Cellulose/Starch Biofilms as Natural Bio-Based Polymers

The antibacterial property of food packaging materials plays a key role in improving the safety and shelf-life of the food. The aim of this study was to evaluate the antibacterial activity of chitosan/carboxymethyl cellulose/starch biofilms against S. aureus and E. coli microorganisms by using agar diffusion disc and optical density methods. Investigation on the properties of fabricated biofilms, including water vapor transmission rate, water solubility, tensile strength and thermal resistance was carried out. Results exhibited that the antibacterial activity was enhanced by increasing the chitosan content. Besides, increased carboxymethyl cellulose content resulted in a decline in the permeability of water vapor through samples. Furthermore, the presence of carboxymethyl cellulose improved tensile strength and thermal stability and reduced the degradation rate of biofilms within the self-life period. Also, the increased starch content in biofilms led to increased water solubility. These results suggested that chitosan/carboxymethyl cellulose/starch biofilms could be used as food packaging materials.