Abstract:
Plastic waste is one of the major threats to the environment, and an urgent need to replace synthetic plastics with sustainable materials is progressively growing. Herein, sustainable films based on chitosan, Satureja, and Thyme essential oils (EOs), and chitosan nanofibers (NF) were developed for the first time. To this end, 1% (w/w) of EOs and 2 wt% of NF were incorporated into the chitosan solution. Despite the very similar chemical structure of carvacrol and thymol, which are the major constituents of Satureja and Thyme EOs, respectively, they imposed notably different effects on the physicochemical properties of chitosan films. Thyme EO was more efficient at establishing hydrogen bonds with chitosan. The disruptive effect of EOs on the crystalline network of chitosan was demonstrated through X-ray diffraction analysis. Satureja and Thyme EOs decreased and increased the barrier property of the chitosan films against water vapor, respectively. However, the barrier property was greatly improved in the presence of chitosan nanofibers. Satureja EO exhibited a more efficient antibacterial property against E. coli rather than Thyme EO. The fruits and vegetables, coated by the chitosan/EO/NF system, were less perished as compared with the control and chitosan-coated samples indicating the promising potential of the developed system to be used as edible and sustainable films and coatings due to their enhanced antibacterial and barrier properties.
摘要:
塑料垃圾是对环境的主要威胁之一,用可持续材料取代合成塑料的迫切需要正在逐步增长。在这里,基于壳聚糖的可持续薄膜,Satureja,和百里香精油(EO),首次开发了壳聚糖纳米纤维(NF)。为此,将1%(w/w)的EOs和2wt%的NF掺入到壳聚糖溶液中。尽管香芹酚和百里酚的化学结构非常相似,它们是Satureja和百里香EO的主要组成部分,分别,它们对壳聚糖膜的理化性质产生了明显不同的影响。百里香EO在与壳聚糖建立氢键方面更有效。通过X射线衍射分析证明了EOs对壳聚糖结晶网络的破坏作用。Satureja和百里香EO降低并增加了壳聚糖膜对水蒸气的阻隔性能,分别。然而,在壳聚糖纳米纤维的存在下,阻隔性能大大提高。SaturejaEO对大肠杆菌而不是百里香EO表现出更有效的抗菌性能。水果和蔬菜,壳聚糖/EO/NF体系包覆,与对照和壳聚糖涂覆的样品相比,其损失较少,这表明开发的系统由于其增强的抗菌和阻隔性能而具有用作可食用和可持续薄膜和涂层的潜力。