Department of Chemistry, Faculty of Arts & Science, Sakarya University, 54187, Sakarya, Turkey.
Food Engineering Department, Faculty of Engineering, Sakarya University, 54187, Sakarya, Turkey.
Int J Biol Macromol. 2023 Jun 30;241:124583. doi: 10.1016/j.ijbiomac.2023.124583. Epub 2023 Apr 25.
The aim of this study is to prepare new packaging materials with improved physical and antimicrobial properties that prevent the growth of microorganisms. Poly(L-lactic acid) (PLA) based packaging films were prepared by the solvent-casting method using spruce resin (SR), epoxidized soybean oil, an essential oil mixture (calendula and clove oil), and silver nanoparticles (AgNPs). The AgNPs were synthesized by the polyphenol reduction method, using spruce resin dissolved in methylene chloride. The prepared films were tested for antibacterial activity and physical properties, such as tensile strength (TS), elongation at break (EB), elastic modulus (EM), water vapor permeability (WVP), and UV-C blocking effect. The addition of SR decreased the water vapor permeation (WVP) of the films, whereas the addition of essential oils (EOs) increased this property due to their higher polarity. The morphological, thermal, and structural properties were characterized using SEM, UV-Visible spectroscopy, FTIR, and DSC. The agar disc well method showed that SR, AgNPs, and EOs imparted antibacterial activity to the PLA-based films against Staphylococcus aureus and Escherichia coli. Multivariate data analysis tools, such as principal component and hierarchical cluster analysis, were used to discriminate PLA-based films by simultaneously evaluating their physical and antibacterial properties.
本研究旨在制备具有改进的物理和抗菌性能的新型包装材料，以防止微生物生长。采用溶剂浇铸法，以云杉树脂（SR）、环氧大豆油、精油混合物（金盏花和丁香油）和银纳米粒子（AgNPs）为原料制备聚（L-乳酸）（PLA）基包装薄膜。AgNPs 通过多酚还原法合成，使用溶解在二氯甲烷中的云杉树脂。对制备的薄膜进行抗菌活性和物理性能测试，如拉伸强度（TS）、断裂伸长率（EB）、弹性模量（EM）、水蒸气透过率（WVP）和 UV-C 阻隔效果。SR 的添加降低了薄膜的水蒸气透过率（WVP），而精油（EOs）的添加由于其较高的极性而增加了这一特性。使用 SEM、UV-可见光谱、FTIR 和 DSC 对形态、热和结构性能进行了表征。琼脂圆盘法表明，SR、AgNPs 和 EOs 赋予 PLA 基薄膜对金黄色葡萄球菌和大肠杆菌的抗菌活性。多元数据分析工具，如主成分和层次聚类分析，用于通过同时评估其物理和抗菌性能来区分 PLA 基薄膜。
