本文研究了3种结构相关的黄酮类化合物:黄芩素(Baicalein)、黄芩苷(Baicalin)和汉黄芩素(Wogo-nin)与Cu2+的配位作用,考察了其络合金属离子的结构特征,并且检测了黄酮类化合物与Cu2+形成配合物后的促氧化活性.用紫外分光光度法扫描黄酮类化合物与Cu2+形成配位后的吸光曲线变化;用电泳法检测了黄酮类化合物与Cu2+形成配合物后对DNA链的氧化损伤.结果表明,这3种黄酮主要是通过A环鳌合Cu2+.黄芩素和汉黄芩素与Cu2+形成配合物后不具有促氧化作用,而黄芩苷与Cu2+形成配合物后仍然具有一定的促氧化作用,能够导致DNA的氧化损伤.
The interactions of copper ion with three structurally related flavonoids (baicalein, baicalin and wogonin) were studied by UV-Vis spectrometry, and the prooxidant activity of these complexes was studied by DNA strand scission assay. The absorbance property of complexes formed by copper ion with flavonoids was studied by UV-vis spectrometry, and the absorbance peak wavelength of flavonoids was recorded with copper ion at different concentration. It was concluded that two absorbance bands of flavonoids shifted when copper ion was added and these flavonoids chelate copper ion by A ring. The DNA strand scission assay was conducted with plasmid DNA, and the results showed that the complexes formed by copper with baicalein or wogonin were not prooxidant, while the copper complex formed with baicalin was prooxidant which caused DNA strand scission, as shown by the conversion of supercoiled DNA to open circular DNA.