Abstract 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.

中文翻译：

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开发活性抗菌聚（L-谷氨酸）-聚（L-赖氨酸）包装材料保护益生菌

摘要 我们研究的主要目标是通过不同 PL 含量（0、2、4 和 6%）的聚赖氨酸 (PL) 开发改性聚谷氨酸 (PG) 薄膜作为微生物反应器，以生长和保护γ-氨基丁酸。 GABA) 产生细菌。使用 FTIR 分析完全证实了在 PG 骨架之间添加了 PL 基团。扫描电子显微照片证实了 PL 对 PG 薄膜微观结构的高度变化。密度、厚度、水分含量、L*（亮度）、b*（黄蓝度）、WI（白度指数）、不透明度和断裂伸长率随着 PL 含量的增加而增加。而 ΔE（总色差）和拉伸强度同时降低。PG-PL 的水蒸气渗透率和 a*（红绿度）值的变化与 PL 含量无关。PG-PL 薄膜是针对食源性病原体（即蜡状芽孢杆菌和大肠杆菌）的活性包装材料。但它们在干燥过程后对益生菌（即短乳杆菌G42）的生存能力没有任何副作用。可以推断，PG-PL 是开发可食用涂层和薄膜的合适候选者，该涂层和薄膜对食源性病原体具有高抗菌性能，而对益生菌的活力没有任何副作用。