College of Biomass Science and Engineering and Healthy Food Evaluation Research Center, Sichuan University, Chengdu 610065, China.
Molecular Toxicology Key Laboratory of Sichuan Provincial Education office, West China School of Public Health and West China Fourth Hospital, Sichuan University, Chengdu 610041, China.
Int J Biol Macromol. 2024 Jul;273(Pt 1):133111. doi: 10.1016/j.ijbiomac.2024.133111. Epub 2024 Jun 12.
In this study, we developed punicalagin-loaded antimicrobial films based on soy protein isolate (SPI) and apple pectin (AP). The AP was derived from apple pomace waste while the punicalagin was obtained from pomegranate peel. Punicalagin was identified to exist in both α- and β-isomers, with the β-type being predominant. The composite films were characterized using scanning electron microscopy, Fourier transformed infrared spectroscopy, X-ray diffraction, and thermogravimetric analysis. Our results demonstrated that the incorporation of AP significantly enhanced the mechanical strength, heat resistance, and barrier properties of the films. Moreover, the composite films integrated with punicalagin exhibited excellent antimicrobial activities against Staphylococcus aureus (with a minimum bactericidal concentration value of 0.25 %), Escherichia coli (with a minimum bactericidal concentration value of 0.50 %), and Aspergillus niger. Finally, these antimicrobial film solutions were tested as coatings on strawberries and found to have significantly better effects on reducing weight loss, improving shelf-life, and maintaining the freshness of strawberries compared to coatings without punicalagin. The results indicate that antimicrobial coatings loaded with punicalagin hold great promise as multifunctional active packaging materials for fruit preservation.
在本研究中，我们开发了基于大豆分离蛋白（SPI）和苹果果胶（AP）的没食子酸单宁负载型抗菌薄膜。AP 来源于苹果渣废物，而没食子酸单宁则来自石榴皮。鉴定出没食子酸单宁存在于 α-和 β-两种异构体中，其中 β-型为主导型。使用扫描电子显微镜、傅里叶变换红外光谱、X 射线衍射和热重分析对复合膜进行了表征。我们的结果表明，AP 的加入显著提高了薄膜的机械强度、耐热性和阻隔性能。此外，负载没食子酸单宁的复合膜对金黄色葡萄球菌（最小杀菌浓度值为 0.25%）、大肠杆菌（最小杀菌浓度值为 0.50%）和黑曲霉均表现出优异的抗菌活性。最后，将这些抗菌膜溶液作为草莓涂层进行测试，结果表明，与不含没食子酸单宁的涂层相比，这些涂层在减少失重、延长货架期和保持草莓新鲜度方面具有显著更好的效果。结果表明，负载没食子酸单宁的抗菌涂层作为水果保鲜的多功能活性包装材料具有广阔的应用前景。
