Enhanced antimicrobial activity of konjac glucomannan nanocomposite films for food packaging

This paper aims at providing a new strategy for developing konjac glucomannan-based antibacterial films with excellent performances. Here, novel nanocomposite films based on photodynamic and photothermal synergism strategy were developed by incorporating graphite carbon nitride nanosheets/MoS2 nanodots (CNMo) into konjac glucomannan (KGM) matrix. Scanning electron microscope, transmission electron microscope, high resolution transmission, high angle annular dark field and element mapping confirmed the successful fabrication of CNMo. The steady and dynamic rheological behavior as well as the good stability of film-forming solution showed that the intermolecular hydrogen bonding was formed. The influences of CNMo content on the structural, mechanical and thermal properties as well as hydrophobicity of KGM films were investigated. This film has a broad-spectrum antibacterial activity. It could prolong the shelf life of cherry tomatoes. Moreover, hemolysis and cells experiment confirm that this film is safe. This strategy is expected to broaden the application of antibacterial packaging. •A novel KGM-based nanocomposite film was successfully constructed.•Photodynamic and photothermal synergetic strategy were applied to KGM-based films.•This film displayed sustained and efficient antimicrobial activity.•This film can effectively preserve cherry tomatoes.•Hemolysis and cells experiment were used to evaluate safety.