Development of active antimicrobial poly (l-glutamic) acid-poly (l-lysine) packaging material to protect probiotic bacterium

• Published in: Polymer testing 2020-03, Vol.83, p.106338, Article 106338
• Main Authors: Karimi, Mozhdeh, Yazdi, Farideh Tabatabaee, Mortazavi, Seyed Ali, Shahabi-Ghahfarrokhi, Iman, Chamani, Jamshidkhan
• Format: Article
• Language: English
• Subjects: Antibacterial; Microbioreactor; Poly glutamic acid; Poly lysine
• ISSN: 0142-9418; 1873-2348
• DOI: 10.1016/j.polymertesting.2020.106338

The main objective of our research was development of a modified poly glutamic acid (PG) films by polylysine (PL) at different PL content (0, 2, 4 and 6%) as a microbioreactor to growth and protect Gamma-aminobutyric acid (GABA) producing bacteria. The addition of PL groups between the PG backbones was completely corroborated using FTIR analysis. Scanning electron micrographs confirmed the high changes in the microstructure of PG films by PL. Density, thickness, moisture content, L* (lightness), b*(yellowness-blueness), WI (whiteness index), opacity, and elongation at break were increased with increasing the PL content. Whereas ΔE (Total color difference) and tensile strength were decreased, simultaneously. The change of water vapor permeability and a* (redness-greenness) value of PG-PL were independent from PL content. The PG-PL films were active packaging material against food borne pathogens (i.e. Bacillus cereus and Escherichia coli). But they had not any side effects on viability of probiotic bacterium (i.e. Lactobacillus brevis G42) after drying process. It is inferable that PG-PL is a suitable candidate for the development of edible coating and film with high antimicrobial properties against food borne pathogen without any side effect on probiotic viability. •A functional food packaging material was developed.•A food packaging system contain microbioreactor was developed.•A simultaneous antibacterial packaging material and probiotic carrier was developed.•A transparence poly (L-glutamic) acid based material was developed.•Characterizations of poly (L-glutamic) acid-poly (l-lysine) film were investigated.