Liu Mei-Yan, Pan Xiao-Li, Li Xue-Bo, Wu Bing
Key Laboratory of the Ministry of Education for the Standardization of Traditional Chinese Medicine, College of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, China.
Sichuan Da Xue Xue Bao Yi Xue Ban. 2021 Mar;52(2):241-247. doi: 10.12182/20201160110.
To synthesize three kinds of metal complexes of aloe-emodin and compare the antioxidant activities of the ligands and the complexes.
Three kinds of aloe emodin metal complex, the aloe-emodin-iron (Ⅱ), the aloe-emodin-copper (Ⅱ) and the aloe-emodin-magnesium (Ⅱ) complexes, were synthesized by dissolving and stirring in anhydrous ethanol solvent, and their structures were characterized. The Fe -H O -methylene blue method, the diphenyl bitter hydrazine radical method (DPPH method) and other assays were used to determine the clearance effect of ligands and complexes on superoxide radicals (O •), hydroxyl radicals (•OH) and phenyl bitter hydrazine radical (DPPH•).
Three kinds of aloe emodin metal complex, the aloe-emodin-iron (Ⅱ), the aloe-emodin-copper (Ⅱ) and the aloe-emodin-magnesium (Ⅱ) complexes, were successfully synthesized. According to the results of structural characterization, we speculated that the aloe-emodin metal complexes were formed at the site between the two molecules of aloe-emodin and one molecule of metal ions (Fe , Mg , Cu ) via the 9 carbonyl and 8 hydroxyl groups of the aloe-emodin molecules. Both the complex and the ligand have clearance effects on three kinds of free radicals, and the complex showed stronger effects than its ligand ( <0.05).
Coordination of aloe-emodin with metal ions, such as Fe , Cu , and Mg , could enhance the antioxidant activity of the ligand itself.
合成三种芦荟大黄素金属配合物，并比较配体及配合物的抗氧化活性。
通过在无水乙醇溶剂中溶解并搅拌，合成三种芦荟大黄素金属配合物，即芦荟大黄素-铁（Ⅱ）配合物、芦荟大黄素-铜（Ⅱ）配合物和芦荟大黄素-镁（Ⅱ）配合物，并对其结构进行表征。采用铁-水-亚甲基蓝法、二苯基苦基苯肼自由基法（DPPH法）等测定配体及配合物对超氧阴离子自由基（O₂•）、羟基自由基（•OH）和二苯基苦基苯肼自由基（DPPH•）的清除效果。
成功合成了三种芦荟大黄素金属配合物，即芦荟大黄素-铁（Ⅱ）配合物、芦荟大黄素-铜（Ⅱ）配合物和芦荟大黄素-镁（Ⅱ）配合物。根据结构表征结果推测，芦荟大黄素金属配合物是通过芦荟大黄素分子的9位羰基和8位羟基，在两分子芦荟大黄素与一分子金属离子（Fe²⁺、Mg²⁺、Cu²⁺）之间形成的。配合物和配体对三种自由基均有清除作用，且配合物的清除效果强于其配体（P<0.05）。
芦荟大黄素与Fe²⁺、Cu²⁺、Mg²⁺等金属离子配位可增强配体本身的抗氧化活性。
