Fabrication and characterization of alkali lignin- kappa carrageenan film for antibacterial material

This study aimed to fabricate flexible films and antibacterial films from kappa carrageenan blended
with alkali lignin. The films were made using a solvent casting method under various kappa carrageenan and
lignin concentrations. The film appearance brown and opaque. With the increasing of lignin content, the color
turned darker brown. The highest mechanical strength of 2.28 MPa and elongation at break of 70.37% was
attained with the addition of 3% lignin, suggesting the improved material flexibility. The increased ultra-violet
(UV) adsorption was also detected when higher lignin contents were added. Furthermore, the alkali lignin
solution showed antibacterial properties against Staphylococcus aureus and Escherichia coli. The results
suggested that the kappa carrageenan/alkali lignin films have great potential to be used as an antibacterial
active food packaging.