低聚壳聚糖芳香醛席夫碱中酚羟基的抑菌活性研究

Study on antibacterial activity of phenol hydroxyl from N-aryl Schiff COS derivatives

以低聚壳聚糖为对象,以苯甲醛、水杨醛、3,4-二羟基苯甲醛为改性试剂,设计合成了一系列含不同酚羟基的O-季铵盐低聚壳聚糖席夫碱衍生物,并对其结构进行了红外光谱或1 H NMR表征。通过抑菌圈法研究其对大肠杆菌和金色葡萄球菌的抑菌活性,结果表明,合成的各种低聚壳聚糖衍生物抑菌活性明显增强,抑菌活性大小依次为3,4-二羟基苯甲醛改性物>水杨醛改性物>苯甲醛改性物>低聚壳聚糖。抑菌活性构效关系分析表明,低聚壳聚糖经席夫碱结构引入的酚羟基对其抑菌活性有一定贡献;其中空间位阻效应对酚羟基抑菌活性影响较大,空间位阻效应较小的间位和对位酚羟基抑菌活性较强。

The N-aryl Chitooligosaccharides（COS）derivatives were firstly synthesized with Benzaldehyde,salicylal and 3,4-two hydroxy benzaldehyde,subsequently was quaternized to enhance its water solubility.The chemical structures of all COS derivatives were characterized by ATR-FTIR or ^1 H NMR.The antibacterial studies of these COS derivatives were carried out by the inhibition zone diameters methods against E.coli,S.aurueus and P.aeruginosa bacteria.The antibacterial activity results showed N-3,4-two hydroxy benzaldehyde Schiff＇s base COS〉 N-salicylal Schiff＇s base COS〉 N-Benzaldehyde Schiff＇s base COS〉 COS.In comparison to the COS derivatives chemical structure,it was found that the phenol hydroxyl group from N-aryl Schiff COS could improved the antibacterial activity,and the samller of its steric hindrance the more high of the antibacterial activity.