Fucoidan as a carrier of antimicrobial peptide: Preparation and characterization of nisin-loaded particles

Fucoidan is an anionic sulphated polysaccharide found in brown seaweed. Due to its various biological activities, biodegradability, and biocompatibility, the application of fucoidan is increasing in various fields. The research was aimed to use fucoidan for nisin encapsulation. Nisin-loaded fucoidan particles were prepared by the complexation method in the pH range of 4.0-7.0. The interaction of nisin and fucoidan was confirmed by FT-IR spectroscopy, dynamic light scattering method, thermogravimetric and differential scanning calorimetry anal-ysis. The stability of the particles was analysed under storage at 4 degrees C. After one month of storage, the hydro-dynamic diameter and zeta potential of particles changed insignificantly. Encapsulated nisin preserved its biological activity. The antimicrobial activity was tested against Gram-positive bacteria Bacillus subtilis and Listeria innocua, and Gram-negative bacteria Escherichia coli and Salmonella typhimurium. Nisin-loaded-fucoidan particles exhibited antibacterial activity against Gram-positive bacteria B. subtilis and L. innocua comparable to free nisin. The application of fucoidan for the encapsulation of nisin is promising. A new nisin formulation could be used in the food industry for biopreservation.