Surfactant assisted nisin loaded chitosan-carageenan nanocapsule synthesis for controlling food pathogens

Nisin loaded chitosan/carageenan nanocapsules were prepared using an ionic complexation method and evaluated for antibacterial activity. Concentration of polymers as well as surfactant affected particle size and encapsulation efficiency. The optimal parameters for synthesis of particles with least size and highest encapsulation efficiency were concentration of caragennan 0.75 mg/ml along with concentration of chitosan 10 mg/ml and surfactant 1 μg/ml. Release study conducted in vitro over a period of two weeks indicated slow and sustained release from the formulation. Furthermore, evaluation of antibacterial activity against Micrococcus luteus MTCC (Microbial Type Culture Collection) 1809, Pseudomonas aeruginosa MTCC 424 and Salmonella enterica MTCC 1253 and Enterobactor aerogenes MTCC2823 in vitro followed by antibacterial activity in tomato juice for six months, indicated that encapsulated nanocapsules showed better antibacterial effect on microbe's in vitro as well as in tomato juice for prolonged periods as compared to the components evaluated separately.