κ-卡拉胶的O-琥珀酰基化衍生物的制备与表征

将κ-卡拉胶(KC)降解成数均分子量为10 060的低分子量卡拉胶(LMW-KC)并制成四丁基铵盐,然后在适宜的反应体系中与琥珀酸酐进行酰化,制备LMW-KC的O-琥珀酰基化衍生物,并进行抗氧化和抑菌试验.同时借助IR、GPC、13C NMR和1H NMR分析手段进行表征.结果表明:KC经降解和酰化后原结构单元未受破坏;60℃酰化的取代度可高达2.60;酰化产物清除羟自由基和H2O2的活性明显增强,抑菌活性也明显增强.

Preparation and Characterization of O-Succinyl Derivative of κ-Carrageenan

Low-molecular-weight κ-carrageenan(LMW-KC)with the number-average molecular weight of 10 060 was achieved by degrading κ-carrageenan(KC)with mild hydrochloric acid,and then was turned into tetrabutylammonium salt.The salt was then acylated with succinic anhydride in the suitable system,resulting in O-succinyl derivatives of LMW-KC.The antioxidant activities and the antibacterial activities of LMW-KC and its derivative were studied.Characterization of the title compounds were performed by IR,GPC,()~(13)C NMR and()~1H NMR.It was displayed that the disaccharide repeating unit of KC was not destroyed after the degradation and acylation.Percentage of succinylate substitution was as high as 2.60 at 60℃;The activities for scavenging hydroxyl radical and H_2O_2 of the acylated derivative were increased apparently,so does its antibacterial activity.