Pleurocidin was found to be effective against foodborne organisms including Vibrio parahemolyticus, L.
monocytogenes, E. coli O157:H7, Saccharomyces cerevisiae, and Penicillium expansum [74]. However, the
antimicrobial effect of pleurocidin was inhibited by magnesium and calcium [75], which may limit the use of these
antimicrobial peptides in environments rich in these cations, magnesium and calcium. Pleurocidin, isolated from the
skin mucus membrane of the winter flounder (Pleuronectes americanus), found active against Gram-positive and Gramnegative
bacteria [75]. Defensins are another group of antimicrobial peptides that are widely found in nature including
mammalian epithelial cells of chickens and turkeys. This antimicrobial peptides are abundant in cells and tissues and
has been reported to have antimicrobial activity against Gram-positive and Gram-negative bacteria, fungi, and viruses
[9]. Other antimicrobial peptides such as protamine and magainin have also been reported to be effective against Gramnegative
and Gram-positive bacteria, yeasts, and molds [9, 76, 77]. Magainin showed to kill Gram-positive bacteria and
reduce the adhesion of bacteria at the surface [77]. However, components of food may interfere with the antibacterial
effects of protamine whereas this undesirable interferences can be reduced by altering the electrostatic properties of
protamine