Mechanical Engineering, Wuhan Polytechnic University, Wuhan 430023, China.
Mechanical Engineering, Wuhan Polytechnic University, Wuhan 430023, China.
Int J Biol Macromol. 2022 Sep 30;217:814-823. doi: 10.1016/j.ijbiomac.2022.07.154. Epub 2022 Jul 27.
Bioactive-packaging films based on polylactic acid (PLA), acetyl tributyl citrate (ATBC), and tea polyphenol (TP) were prepared by melt blending. Results of mechanical-property test revealed that adding ATBC and TP can significantly improve mechanical properties of PLA. The shift of CO to lower wavelengths in FTIR and the morphology of the films in SEM indicated physical or chemical interactions in the PLA/ATBC/TP films. The antioxidant, and antibacterial activities of the PLA/ATBC films increased dramatically (P<0.05) with increased TP amount. The antioxidant activity of the films with 1 % TP was equivalent to that of 300 mg/L l-ascorbic acid, whereas PLA/ATBC/TP films with 0.5 % and 1 % TP concentration were effective in inhibiting Staphylococcus aureus and Escherichia coli within almost 5 h (P<0.05). The PLA films changed from transparent to opaque and from yellow to red after combining with ATBC or TP, respectively. The overall migration of the films in 3 % acetic acid and 10 % ethanol did not exceed the overall migration limit. All these findings indicated potential of the PLA/ATBC/TP films in active-packaging application.
基于聚乳酸（PLA）、乙酰柠檬酸三丁酯（ATBC）和茶多酚（TP）的生物活性包装薄膜通过熔融共混制备而成。力学性能测试结果表明，添加 ATBC 和 TP 可以显著提高 PLA 的力学性能。FTIR 中 CO 向低波数的移动以及 SEM 中薄膜的形态表明 PLA/ATBC/TP 薄膜中存在物理或化学相互作用。随着 TP 含量的增加，PLA/ATBC 薄膜的抗氧化和抗菌活性显著提高（P<0.05）。含 1%TP 的薄膜的抗氧化活性相当于 300mg/L L-抗坏血酸，而浓度为 0.5%和 1%TP 的 PLA/ATBC/TP 薄膜在近 5 小时内有效抑制金黄色葡萄球菌和大肠杆菌（P<0.05）。PLA 薄膜与 ATBC 或 TP 结合后分别从透明变为不透明，从黄色变为红色。在 3%乙酸和 10%乙醇中的薄膜整体迁移量未超过整体迁移限量。所有这些发现表明 PLA/ATBC/TP 薄膜在活性包装应用中具有潜力。
