Development of multifunctional bacterial cellulose film modified with polymeric tryptophan-anion-based imidazolium ionic liquid for enhanced berry preservation

Water loss, oxidation, and microbial infection can degrade berries, highlighting the need for versatile, eco-friendly packaging. A novel tryptophan-Anion-Based ionic liquid modified reagent, 1-vinyl-3-aminopropyl imidazole-tryptophan ([vaim][Trp]), was synthesized and utilized for crafting a multifunctional bacterial cellulose (BC) packaging film (BC-CTA@PIL) via grafting polymerization. The optimized BC-CTA@PIL showcased superior tensile strength (5.42 MPa), modulus (152.24 MPa), oxygen and water vapor barrier capabilities due to the multiple interactions between polymeric [vaim][Trp] chains and BC macromolecules. Owing to the aromatic heterocyclic structure present in [vaim][Trp], the BC-CTA@PIL can achieve a free radical scavenging rate of 67.78 %. The multi-amino and hydrophobic functional groups within the polymeric [vaim][Trp] of BC-CTA@PIL synergistically contribute to its antibacterial efficacy, with inhibition rates of over 95 % against four Gram negative and positive bacterial strains. The BC-CTA@PIL revealed a high cell survival rate of 93.03 % for hamster lung cells. Therefore, BC-CTA@PIL could effectively preserving moisture and nutrients in berries, thereby extending their shelf life.