Antibacterial Activity of Bacillus Lipopeptides Vehiculized and Delivered by Biopolymeric Films

Abstract

Active films based on different biopolymers (pectin, Brea gum, carboxymethylcellulose, and composite starch-gelatin) were prepared by casting. Lipopeptides synthesized by bacteria of the Bacillus genus were added as antimicrobial active agent. Antibacterial activity was evaluated and quantified by direct contact technique against different strains of Listeria monocytogenes, Escherichia coli, and Salmonella enterica sp. Incorporation of lipopeptides did not cause significant changes in mechanical and barrier properties of films. Antibacterial effect of functionalized films depended on the nature of the polymeric matrix and the pathogen studied. Functionalized pectin films inhibited the growth of all strains studied, with non-functionalized pectin films also showing inhibition of L. monocytogenes. Functionalized starch-gelatin films only inhibited the growth of L. monocytogenes. The other matrices did not show adequate performance for this type of application. The results suggested that pectin and starch-gelatin composite can be used as effective lipopeptide carriers to produce antimicrobial active films for food preservation.