Diffusion and Antibacterial Properties of Nisin-Loaded Chitosan/Poly (L-Lactic Acid) Towards Development of Active Food Packaging Film

• Published in: Food and bioprocess technology Vol. 8; no. 8; pp. 1657 - 1667
• Main Authors: Wang, Hualin, Liu, Huan, Chu, Chengjiang, She, Yi, Jiang, Suwei, Zhai, Linfeng, Jiang, Shaotong, Li, Xinjiang
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.08.2015; Springer Nature B.V
• Subjects: Agriculture; antibacterial properties; Antimicrobial activity; Antimicrobial agents; Biotechnology; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Chitosan; Controlled release; Diffusion; Elongation; Food packaging; Food Science; Hydrogen bonding; Hydrogen bonds; Ionic strength; Lactic acid; Mechanical properties; Nisin; Original Paper; packaging films; pH effects; Polylactic acid; Staphylococcus aureus; Tensile strength; thermodynamics; Nisin-loaded chitosan/poly (L-lactic acid); Antimicrobial behavior; Diffusion kinetics; Active food packaging; Diffusion thermodynamics; Controlled release
• ISSN: 1935-5130; 1935-5149
• DOI: 10.1007/s11947-015-1522-z

Nisin-loaded chitosan/poly (L-lactic acid) (nisin-CS/PLLA) antimicrobial films were prepared by coating method. The structure and mechanical properties of nisin carrier CS/PLLA films were investigated, and the antibacterial behavior of nisin-CS/PLLA against Staphylococcus aureus ATCC6538 was assessed. Furthermore, the diffusion behaviors of nisin from films were evaluated by diffusion kinetics and thermodynamics, and the diffusion efficiency was investigated as a function of CS/PLLA ratio, pH, and ionic strength. When CS/PLLA ratio was at 1:1 (w/w) and above, a notable enhancement was observed in the tensile strength with the increase of PLLA content, while the elongation at break was decreased slightly at the same time. However, a significant decrease in tensile strength and elongation at break were present when the CS/PLLA ratio was below 1:1. There existed intermolecular hydrogen bonds between CS and PLLA molecules. The diffusion of nisin from film was strongly dependent on pH and ionic strength. The thermodynamic parameters (ΔH ᵒ , ΔS ᵒ , and ΔG ᵒ) indicated that the diffusion process of nisin from film was spontaneous and endothermic. From diffusion and antimicrobial activity results, nisin-CS/PLLA films revealed well-controlled release and better antimicrobial activity against S. aureus, which may have potential as a novel active food packaging film.