Abstract Gum karaya (GK) is an inexpensive and abundant source of polysaccharides in tropical countries. GK can be used for biodegradable film preparation without further extraction. In this study, active GK nanocomposite films containing Cloisite Na+ (CLS) and cinnamaldehyde (CIN) were developed. The physical properties of the GK films were examined. The dispersion of GK (2.5%, w/v) and glycerol (55% of gum, w/w) exhibited film-forming capacity. Addition of CLS enhanced the physical properties of the films by the intercalation of GK molecules into the layered structure of CLS nanoparticles. This structure was elucidated in the X-ray diffraction pattern of the GK nanocomposite films. In particular, the tensile strength of the GK film containing 11% CLS was increased by 73%, compared to that of the GK film without CLS. Water solubility and water vapor permeability of the GK films were decreased with the addition of CLS. Moreover, the incorporation of 0.25%, 0.50%, and 0.75% CIN caused the increase in elongation at break of the GK film containing 11% CLS by 60%, 82%, and 43%, respectively. Furthermore, the addition of CLS and CIN increased the opacity of the GK films. The GK film containing 11% CLS and 0.75% CIN exhibited antimicrobial activities against the tested pathogens. Thus, the results in this study suggest that the GK/CLS nanocomposite films containing CIN can be applied as an active packaging material.

中文翻译：

---

含有肉桂醛的活性胶刺梧桐/Cloisite Na+纳米复合薄膜

摘要 刺梧桐树胶 (GK) 是热带国家廉价且丰富的多糖来源。GK 可用于制备可生物降解的薄膜，无需进一步提取。在这项研究中，开发了含有 Cloisite Na+ (CLS) 和肉桂醛 (CIN) 的活性 GK 纳米复合薄膜。检测了 GK 薄膜的物理性能。GK（2.5%，w/v）和甘油（55% 的树胶，w/w）的分散体表现出成膜能力。通过将 GK 分子嵌入到 CLS 纳米粒子的层状结构中，CLS 的添加增强了薄膜的物理性能。这种结构在 GK 纳米复合薄膜的 X 射线衍射图中得到了阐明。特别是，与不含 CLS 的 GK 薄膜相比，含有 11% CLS 的 GK 薄膜的拉伸强度提高了 73%。GK 薄膜的水溶性和水蒸气渗透性随着 CLS 的加入而降低。此外，0.25%、0.50% 和 0.75% CIN 的掺入导致含有 11% CLS 的 GK 薄膜的断裂伸长率分别增加了 60%、82% 和 43%。此外，CLS 和 CIN 的加入增加了 GK 薄膜的不透明度。含有 11% CLS 和 0.75% CIN 的 GK 薄膜对测试的病原体表现出抗菌活性。因此，本研究的结果表明，含有 CIN 的 GK/CLS 纳米复合薄膜可用作活性包装材料。此外，CLS 和 CIN 的加入增加了 GK 薄膜的不透明度。含有 11% CLS 和 0.75% CIN 的 GK 薄膜对测试的病原体表现出抗菌活性。因此，本研究的结果表明，含有 CIN 的 GK/CLS 纳米复合薄膜可用作活性包装材料。此外，CLS 和 CIN 的加入增加了 GK 薄膜的不透明度。含有 11% CLS 和 0.75% CIN 的 GK 薄膜对测试的病原体表现出抗菌活性。因此，本研究的结果表明，含有 CIN 的 GK/CLS 纳米复合薄膜可用作活性包装材料。