Formation mechanism of nano-scale antibiotic and its preservation performance for silvery pomfret

To improve the antibacterial stability, a self-assembly method was applied. The typical antibiotic of nisin was loaded in chitosan nanoparticles (Nano-N) which was used as a carrier of antibiotics. The characteristics and formation mechanism of nano-scale antibiotic as well as its preservation properties on silvery pomfret were investigated. The results exhibited that the nano-scale antibiotics were nearly sphere-like with the mean size of 150 nm. The formation of nano-scale antibiotics was attributed to interactions among the functional groups of chitosan, sodium tripolyphosphate and nisin by hydrogen bonds and electrostatic interactions. Meanwhile, the preservation effects to silvery pomfret by the nano-scale antibiotic coatings were better than nisin or chitosan nanoparticle coating alone, which was ascribed to a more efficient prevented oxygen, microorganism as well as protein degradation from silvery pomfret by the self-assembled nano-scale antibiotic coating. Thus, it could extend the shelf life of fish by 3 d-9 d, suggesting that nano-nisin coating have great potential in the seafood preservation field.