Antimicrobial Potential of Polylysine in Edible Films

Abstract

The antimicrobial activity of edible films from whey proteins, alginate, zein and chitosan incorporated with polylysine (PL) and PL-ethylenediaminetetraacetic acid (Na₂EDTA) combination have been tested on different bacteria including Escherichia coli, Listeria innocua, Salmonella Typhimurium and Stapylococcus aureus. The PL-containing films of whey proteins, alginate and chitosan were effective on L. innocua, but had limited effect on E. coli. On the other hand, the PL-containing zein films showed good antimicrobial activity on both E. coli and L. innocua as well as on S. aureus. PL-Na₂EDTA combination also gave zein films effective on S. Typhimurium. The incorporation of PL alone or PL-Na₂EDTA combination did not cause any significant change in mechanical properties of zein films. Zein has a good potential to develop novel antimicrobial packaging materials incorporated with PL.