Preparation and Characterization of Piper Betle Linn. Leaf Extract Incorporated Chitosan Films as Potential Active Food Packaging Materials

The present paper reports on the preparation and characterization of potential edible packaging films based on the combination of chitosan and Piper betle Linn. leaf extract (PBLLE). The incorporation of PBLLE was found to improve important characteristics of the chitosan film, making it ideally suitable for active packaging applications. In particular, the blend films exhibited very strong inhibitory activities against both gram-negative and gram-positive bacteria such as Bacillus subtilis and Salmonella Typhimurium. Moreover, IC50 values of the blend films were recorded at low levels (10.63- 22.81 mu g/mL) in the PBLLE range of 1-3% v/v. Both antimicrobial and antioxidant activities of the blend films increased with increasing incorporated PBLLE content (from 1 to 3% v/v) taking into account the activities of polyphenolic compounds contained in the extract. Compared to the pure chitosan film, a significantly lower swelling degree, higher resistance to water vapor permeation and desired flexibility were recorded for the films with sufficient extract content. Interestingly, no considerable difference in the thermal stability of the pure chitosan and the blend films was detected in thermal analysis. In addition, effects of PBLLE on other mechanical and optical properties of the blend films were also examined in detail.