Department of Natural Resources and Environmental Engineering, School of Agriculture, Shiraz University, Shiraz, Iran.
Department of Natural Resources and Environmental Engineering, School of Agriculture, Shiraz University, Shiraz, Iran.
Int J Biol Macromol. 2021 Jul 31;183:1743-1752. doi: 10.1016/j.ijbiomac.2021.05.159. Epub 2021 May 26.
In this study, active antibacterial cross-linked composite films were prepared through incorporating ε-poly-l-lysine (ε-PLL) into Siberian sturgeon gelatin-chitosan mixture. Cross-linking was performed by Glutaraldehyde (G) and/or Cinnamaldehyde (C). The antimicrobial, ε-PLL release, mechanical and morphological properties were then investigated. The addition of G to the biopolymer mixture significantly resulted in lower water vapor permeability, enhanced mechanical strength, lower moisture content, and water solubility. The FTIR spectra indicated the formation of imine bonds in the composite film network. The microstructure of composite films was affected by the cross-linking agent. The films cross-linked by G and C showed smooth and rough surfaces, respectively. C induced very small pores in the cross-section of the composite film. The composite films incorporated with ε-PLL revealed higher and steady-state in vitro antimicrobial properties against food spoilage bacteria. A higher release of ε-PLL and hence higher antibacterial activity was measured in the matrices cross-linked by C than those cross-linked by G. The results showed that the ε-PLL-fortified fish gelatin/chitosan composite films can be considered as a food-packaging material. G and C, as cross-linkers, can improve the structural and antimicrobial properties of this composite film.
在这项研究中，通过将 ε-聚赖氨酸（ε-PLL）掺入西伯利亚鲟鱼明胶-壳聚糖混合物中，制备了具有活性抗菌作用的交联复合膜。交联是通过戊二醛（G）和/或肉桂醛（C）进行的。然后研究了抗菌、ε-PLL 释放、机械和形态特性。将 G 添加到生物聚合物混合物中，显著降低了水蒸气透过率、提高了机械强度、降低了水分含量和水溶性。FTIR 光谱表明在复合膜网络中形成了亚胺键。复合膜的微观结构受交联剂的影响。用 G 和 C 交联的膜分别呈现出光滑和粗糙的表面。C 在复合膜的横截面中诱导了非常小的孔。掺入 ε-PLL 的复合膜对食品腐败细菌表现出更高和稳定的体外抗菌性能。在 C 交联的基质中测量到更高的 ε-PLL 释放，因此具有更高的抗菌活性，而在 G 交联的基质中则较低。结果表明，ε-PLL 强化的鱼明胶/壳聚糖复合膜可用作食品包装材料。G 和 C 作为交联剂，可以改善这种复合膜的结构和抗菌性能。
