Enhanced antioxidant and antimicrobial activities of chitosan/oxidized microcrystalline cellulose blended films with Tribulus terrestris extract for food packaging applications.

Chitosan/oxidized cellulose blended film with Tribulus terrestris (T. terrestris) extract films were successfully produced by casting method. The obtained blend films were characterized by structural, mechanical, optical, permeation, antioxidant, and antimicrobial properties. Finally, these biodegradable blend films were used to prolong the shelf-life of sour cherries. Remarkable physical properties such as water vapor transmission rate, swelling, water solubility, mechanic strength, and UV-vis light transmittance were observed to improve positively. All blend films showed 60-70 % degradation after 30 days of hydrolytic degradation and soil burial. T. terrestris extract increased the tensile strength from 1.1 MPa to a maximum of 2.1 MPa and elongation at break from 16 % to 46 %. Furthermore, blend films with T. terrestris extract showed ~4 and ~ 3.7 times higher ABTS and DPPH scavenging potential, respectively. Moreover, the findings also revealed that blend films displayed strong antimicrobial activity against S. aureus, E. coli, and C. tropicalis. Most importantly, the shelf life of sour cherries packaged with blend films was effectively extended up to 10 days. Overall, blended films are a promising potential alternative material to petroleum-based synthetic plastics for use in active food packaging, especially in products with short shelf life such as sour cherry.