儿茶酚香豆素清除自由基能力测定及作用机制探索  

Free Radical Scavenging Capability of Catechol Coumarins and Mechanism

作　　者：陆俊霞 李珂珂[3] 王平[2] 崔攀[2] 陈丽荣[1] 弓晓杰[3] 

机构地区：[1]大连大学环境与化学工程学院,辽宁大连116622 [2]中国科学院大连化学物理研究所药用资源开发实验室,辽宁大连116023 [3]大连大学医学院,辽宁大连116622

出　　处：《中国现代中药》2016年第5期573-578,共6页Modern Chinese Medicine

基　　金：国家自然科学基金(81172949);辽宁省优秀人才支持计划(LR2013058);辽宁省自然科学基金计划(2015020657);辽宁省科技厅科学技术计划(2014204007);大连市科技局科技计划(2014E12SF071)

摘　　要：目的:测定儿茶酚香豆素清除自由基的能力,并研究其作用机制。方法:测定系列不同浓度的4-取代、8-含氮氢键受体和单甲基化儿茶酚香豆素衍生物对DPPH、ABTS·+自由基的清除率,绘制浓度-清除率曲线,结合文献报道的酚类化合物清除自由基的作用机制,研究儿茶酚类香豆素清除自由基的作用机制。结果:所有被测儿茶酚香豆素化合物都具有良好的抗氧化活性,其对ABTS·+自由基的清除能力强于对DPPH的清除能力。当引入含氮氢键受体,形成分子内氢键后,其对DPPH自由基的清除能力减弱,而对ABTS·+的清除能力没有明显变化。当儿茶酚香豆素被单甲基化后,其清除自由基的活性明显下降。结论:儿茶酚类香豆素清除DPPH自由基的作用机制和酚羟基的氢原子转移有关,而清除ABTS·+的作用方式可能是质子丢失,电子转移。Objective： To evaluate free radical scavenging capacity of catechol coumarin, and further explore the mechanism of the reaction between catechol coumarins and free radical. Methods ： DPPH, ABTS·^＋ scavenging activity of a series of coumarins including substituent group at position 4, 8 and monomethylation products were assayed, then the curve of logc-scvenging activity was drawn. Finally, the free radical scavenging mechanism of catechol compounds was explored according to the literature. Results： All of compounds investigated possessed excellent antioxidant activity, and the ability to get rid of ABTS·^＋ was stronger than that of DPPH. The ability of getting rid of DPPH was reduced by introducing nitrogen-containning groups, which acting as hydrogen bond acceptors for formation of intramolecular hydrogen bonds, while no significant changes in ABTS·^＋ were found. However, the antioxidant activity decreased significantly, even to inactivation, for monomethylation of catechol coumarins. Conclusion： The mechanism complies with Hydrogen Atom Transfer （HAT） for scavenging DPPH, while sequential proton loss electron transfer may be more appropriate for ABTS·^＋.

关 键 词：儿茶酚香豆素 自由基 作用机制 

分 类 号：R979.6[医药卫生—药品]