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作 者:孙涛[1] 银旭红[1] 甘建红[1] 赖克强[1] 周冬香[1]
出 处:《天然产物研究与开发》2010年第5期890-893,共4页Natural Product Research and Development
基 金:上海市教育委员会科研项目(07zz134);上海市教委重点学科建设项目专项基金(J50704)
摘 要:低聚壳聚糖(COS)酰化得到三种取代度(DS)不同的N-马来酰低聚壳聚糖衍生物NMCOSA、NMCOSB和NMCOSC,其DS分别为0.25、0.67和0.89。对其结构进行红外表征。并考察了NMCOSA、NMCOSB和NMCOSC对羟基自由基(.OH)、1,1-二苯基苦基苯肼(DPPH)的清除活性以及还原能力。结果表明:N-马来酰衍生物有明显的抗氧化活性,随着取代度的升高,N-马来酰衍生物清除DPPH的能力以及还原能力增强,即NMCOSC>NMCOSB>NMCOSA;清除.OH的活性顺序为NMCOSB>NMCOSA>NMCOSC,即取代度为0.67的表现出最强的活性。这可能与氨基和羟基的数目、取代基团的性质以及清除自由基的机理不同有关。N-maleoyl chitosan oligosaccharides(NMCOSA,NMCOSB and NMCOSC) with different substituting degrees(DS were 0.25,0.67 and 0.89,respectively) were prepared by chemical modification of chitosan oligosaccharide(COS).The chemical structures of the chitosan oligosaccharides derivatives were characterized by FTIR.Their antioxidant activities were evaluated by the scavenging of hydroxyl radical(·OH),1,1-Diphenyl-2-picrylhydrazyl radical 2,2-Diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl(DPPH) and reducing power.The results indicated that the N-maleoyl chitosan oligosaccharides derivatives have obvious antioxidant activity,the scavenging effects on DPPH and the reducing power were all increased with the increasing of the substituting degree:the orders of their scavenging effects on ·OH was NMCOSBNMCOSANMCOSC,the NMCOSB showed the best scavenging effects on ·OH.That may be related with the number of the amino and hydroxyl groups,the properties of the substituting groups and the different scavenging mechanisms against free radicals.
关 键 词:低聚壳聚糖 N-马来酰低聚壳聚糖衍生物 取代度 抗氧化
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