The Release of Egg White Lysozyme Containing EDTA from Composite Edible Film Based on Whey Protein, Konjac Flour and Lipid

Abstract

The objectives of this research were to find out the effect of EDTA addition on antibacterial spectrum broadening of lysozyme on Gram negative bacteria and the release of lysozyme from composite edible film made of whey protein, konjac glucomannan and several lipids type and content. The research were conducted with 2 steps. Step I: The addition of EDTA on lysozyme aquaeous (Lysozyme (mg/mL): EDTA (mg/mL) = 11.14:8.14; 11.14:11.14 and 11.14:14.14) using Randomyzed Block Design, the variables were, antibacterial of lysozyme on Micrococcus lysodeikticus and Escherichia coli. Step II: Lipid content (5 and 10%) and kind of lipid (butter, margarine, palm oil and beeswax) using nested Randomyzed Block Design, the variables were lysozyme release, Water Vapor Permeability (WVP), protein solublity and microstructure of composite edible film. The results were, step I: the treatment didn't gave significantly effect (p>0.05) on lysozyme activity. EDTA decrease cell membrane stabilization and lysozyme made lysis of cell membrane. EDTA chelate Ca 2+ and Mg 2+ salts as bridge between Lypopolysachcharide (LPS) in outer membrane so LPS released from cell wall of Gram negative bacteria. Step II: The treatment didn't gave significantly effect (p>0.05) on release of lysozyme and water vapour permeability, but gave significantly effect (p<0.05) on protein solubility. The release of lysozyme from composite edible film gave the best lysozyme release from beeswax 10% addition.