羧甲基壳聚糖席夫碱的制备及抗菌性能研究

在超声波作用下,以自制的低分子量羧甲基壳聚糖与香草醛为原料,制备了低分子量羧甲基壳聚糖香草醛席夫碱。利用FI-IR对其结构进行了表征,研究了香草醛与羧甲基壳聚糖中氨基的反应摩尔比、反应温度、反应时间及超声波功率对产物氨基取代度的影响。结果表明：当香草醛与羧甲基壳聚糖中氨基的摩尔比为1∶0.8、反应时间为3 h、反应温度为70℃、超声波作用功率为70 W时,羧甲基壳聚糖香草醛席夫碱的氨基取代度可达到82.5%;将羧甲基壳聚糖席夫碱与羧甲基壳聚糖的抗菌性能进行了比较,发现羧甲基壳聚糖香草醛席夫碱对金黄葡萄球菌和大肠埃希菌的抑菌圈宽度分别比羧甲基壳聚糖的抑菌圈宽0.7 mm和0.5 mm。

Preparation and Antibacterial Properties of Carboxymethyl Chitosan Schiff Base

The caiboxymethyl chitosan vanilline Schiff base was synthesized by carboxymethyl chitosan of low molecule weight and vanillin under ultrasonic. The structure of caiboxymethyl chitosan and vanilline Schiff base was characterized by fourier transform infrared （FT-IR） spectroscopy. The effect of molar ratio of carboxymethyl chitosan and vanilline, reaction time, reaction temperature and operation power on amion substitution degree was studied. The results showed that amino substitution degree of caiboxymethyl chitosan and vanilline Schiff base was 82.5% when the molar ratio of caiboxymethyl chitosan and vanilline was 1 ： 0.8, the reaction time was 3 h, the reaction temperature was 70℃ and the operating power was 70 W. The antibacterial property of carboxymethyl chitosan and caiboxymethyl chitosan vanilline Schiff base was tested. It showed that the inhibition zone of caiboxymethyl chitosan vanilline Schiff base to E.coli was 0.7 mm wider than caiboxymethyl chitosan＇s and the inhibition zone of caiboxymethyl chitosan vanilline Schiff base to S.aureus was 0.5 mm wider than caiboxymethyl chitosan＇s respectively.