Bio-active packaging films from cellulose acetate incorporated with cypress essential oil (Cyp) have been developed. Thus, cellulose acetate (CA), which is a biodegradable and renewable polymer has been used as an alternative to petroleum-based polymers. Cellulose acetate films were prepared via a solvent casting method incorporating 0, 10, 30, and 60% (w/w) of Cyp. The purpose was to evaluate the possible changes caused by the Cyp on the properties of the packaging films. Different methods and technics have been used to characterize these films. The antibacterial and antioxidant properties of the films were also analyzed. FTIR and XRD analysis indicated that Cyp was homogenously distributed in the films. Meanwhile, TGA analysis demonstrated that the addition of Cyp had an impact on thermal-oxidative properties of the films. The CA/Cyp films showed excellent biodegradability in soil after 60 days, with a percentage loss of 87.07% by mass, and improved mechanical properties with tensile strength and elongation-at-break of 8.1 +/- 0.2 MPa and 16.6 +/- 0.2%, respectively. Water absorption and water solubility values for CA/Cyp films ranged from 76.62 +/- 0.91% to 21.95 +/- 0.57% and from 1.29 +/- 0.35 to undetectable levels, respectively. The results displayed that antibacterial activity against Escherichia coli and Staphylococcus aureus increased as the percentage of Cyp increased in the cellulose acetate films. Moreover, the free radical scavenging activity of cellulose acetate films was improved by increasing the Cyp concentration. These results indicate that cellulose acetate films containing a low-cost essential oil like Cyp have potential for use as active packaging for foods.

The objective of this study was to produce new active and intelligent high performance colorimetric films based on cellulose acetate (CA), and to evaluate the synergistic effect of thymol (THY) and anthocyanin (ANT). The colour films showed significant reactivity to pH change, and the films became thicker in the presence of glycerol (0.200 +/- 0.05). FTIR and SEM images showed a homogeneous distribution and new interactions created between THY, ANT and CA, which modified the thermal properties. This behaviour was also confirmed by XRD analysis, which showed a reduction in film crystallinity with increasing anthocyanin concentration. In addition, the incorporation of ANT improved the mechanical properties by reducing the tensile strength (0.075 +/- 0.021 MPa), the biodegradability of the films in the soil after 60 days and also the water vapor transmission rate (14.81 g mm-2 h-1). The films showed synergistic antibacterial activity and the application trials showed colour changes that were highly visible to the naked eye, with the deterioration of the fish, suggesting a promising application for these films as an indicator of fish freshness.