Mechanical, antibacterial and biodegradable properties of starch film containing bacteriocin immobilized crystalline nanocellulose.

We reported the preparation of antibacterial corn starch film (57% reduction in bacterial count) with enhanced tensile strength (69%) by incorporating immobilized bacteriocin. Whisker shaped crystalline nanocellulose (CNC, length 71.2 ± 20.7 nm and width 27.8 ± 11.2 nm) was prepared from cotton linters by bio-mechanical process, having the degree of polymerization 250. Bacteriocins extracted from broth cultures of P. acidilactici and E. faecium were immobilized on the surface of CNC and used to reinforce the starch film. The biodegradability of reinforced films was affected due to the use of bacteriocin in fillers. Surface morphology and roughness of reinforced films were studied by SEM and AFM. In an ambient environment, the films incorporated with bacteriocin immobilized CNC stayed fresh for 28 days while that of bacteriocin alone had fungal degradation in 14 days. This supports the requirement of CNC immobilization for better stability of bacteriocin on storage.