N-琥珀酰壳聚糖固载溶菌酶抑菌膜的制备、性能及应用研究

发布时间：2018-06-15 23:16

  本文选题：N-琥珀酰壳聚糖 + 溶菌酶　； 参考：《吉林大学》2017年硕士论文

【摘要】：本文通过琥珀酰酐与壳聚糖的酰化反应制备了N-琥珀酰壳聚糖(NSC),利用FTIR、1HNMR证明壳聚糖与琥珀酰酐的反应是发生在壳聚糖的N-位,利用XRD分析表明,N-琥珀酰壳聚糖的结晶性降低,是壳聚糖水溶性加大的原因。通过p H,EDC/NHS、溶菌酶的添加量等单因素试验,确定制备NSC-LSZ(以N-琥珀酰化壳聚糖为载体固载溶菌酶的产物)的最佳条件为:p H为6.0,EDC、NHS分别为20 mg,溶菌酶为100 mg。在最佳条件下,酶的固载量可达89.04%;利用FTIR和CD对NSC-LSZ的二级结构进行表征,发现以N-琥珀酰壳聚糖固载的溶菌酶的二级结构发生变化,主要是因为溶菌酶与N-琥珀酰壳聚糖发生共价结合导致;通过TGA发现,NSC-LSZ的热稳定相对提升;经抑菌性试验和LDH细胞毒性试验发现,NSC-LSZ的抑菌性良好,安全无毒。将NSC-LSZ做成涂膜液用于草莓的室温保鲜,草莓的保鲜时间可达6 d,与不做任何处理的草莓相比,保鲜时间可以延长3 d;通过对草莓的失重率、质构、维生素C含量、p H进行分析,发现NSC-LSZ的抑菌保鲜效果良好。通过流涎法制膜,探究温度、干燥时间、甘油添加量对膜性能的影响,发现在在NSC-LSZ溶液中添加5%(wt)的甘油,在40℃条件下干燥7 h,制得的薄膜的阻水、隔氧、透光性、拉伸强度、断裂伸长率等性能较好。
[Abstract]:N- succinyl chitosan (NSCN) was prepared by acylation of succinic anhydride with chitosan. The reaction between chitosan and succinic anhydride was confirmed by FTIR ~ 1H NMR. XRD analysis showed that the crystallinity of N-succinyl chitosan was decreased. This is the reason for the increase in water solubility of chitosan. The optimum conditions for the preparation of NSC-LSZ (supported lysozyme by N succinylated chitosan) were determined by single factor experiments, such as the amount of lysozyme and the amount of lysozyme. The optimum conditions were as follows: the ratio of% H to 6.0 mg and lysozyme to 100 mg. The optimum conditions for preparation of NSC-LSZ were as follows:% H = 6.0 mg, EDCN / NHS = 20 mg and lysozyme 100 mg, respectively. The secondary structure of NSC-LSZ was characterized by FTIR and CD, and it was found that the secondary structure of lysozyme supported by N-succinyl chitosan changed. It was mainly due to the covalent binding of lysozyme and N-succinyl chitosan; the relative improvement of thermal stability of NSC-LSZ was found by TGA; and the bacteriostatic property of NSC-LSZ was good and safe and non-toxic by bacteriostatic test and LDH cytotoxicity test. Using NSC-LSZ as coating solution to keep strawberry fresh at room temperature, the preservation time of strawberry can be up to 6 days, which can be prolonged by 3 days compared with strawberry without any treatment, and the weight loss rate, texture and vitamin C content of strawberry are analyzed. It was found that NSC-LSZ had a good effect on bacteriostasis and fresh-keeping. The effects of temperature, drying time and glycerol addition on the properties of the film were investigated. It was found that the film was prepared by adding 5% glycerol in NSC-LSZ solution and drying at 40 鈩，

本文编号：2024065