摘要
采用荧光、紫外及红外等光谱方法研究了在水溶液中锌离子对槲皮素、杨梅素与牛血清蛋白(BSA)相互作用的影响。槲皮素和杨梅素均能使BSA的荧光发生淬灭,表明两种药物与BSA发生了结合。锌离子的加入则能进一步导致BSA的荧光淬灭,同时,使BSA的特征发射光谱产生了显著的蓝移,其中锌离子对杨梅素的影响甚于槲皮素,表明锌离子的存在能够显著影响两种药物与BSA的相互作用,其影响的程度与药物分子结构中B环的羟基数相关。定量计算表明,加入锌离子后2种药物与BSA间的结合常数显著降低、结合位点数减小。红外和紫外吸收光谱结果显示,锌离子与槲皮素、杨梅素发生了配位反应,形成了新的配合物。可以推断,在锌离子存在下,槲皮素和杨梅素与BSA的结合在很大程度上分别是两种药物的锌配合物与其相互作用,槲皮素、杨梅素等黄酮类药物B环羟基数的增加能够使药物与BSA的结合能力增强,而锌离子的存在反而使其结合能力减弱。
The effect of Zn^2＋ on the interactions between Quercetin （Que）, Myricetin （Myr）, two typical naturally occurring biologically-active molecules, and bovine serum albumin （BSA） was investigated by means of fluorescence, infrared and ultraviolet spectroscopic methods. The fluorescence intensity of BSA decreased remarkably upon addition of both Que and Myr, respectively, exhibiting that each compound binds to BSA in aqueous solution. When appropriate amount of Zn^2＋ was added to the mixture of BSA and Que or Myr, the fluorescence of BSA decreased again accompanied by appreciable blue-shift of its maximum emission wavelength, among which the changes resulted by Myr are more noticeable than Que. The results indicate that Zn^2＋ can exert some effects on the interactions of both Myr and Que with BSA, and the effects are related to the number of the hydroxyl in B ring of the molecule. The quantitative calculation shows that the binding constant and the number of binding sites of both compounds decreases in the presence of Zn^2＋. The infrared spectrum and ultraviolet spectra indicate that Zn^2＋ binds to both Que and Myr, forming Zn^2＋ complex, respectively. The effect of Zn^2＋ on the interactions of Que, Myr with BSA in aqueous solution may be ascribed to the zinc complex formation. Increasing number of hydroxyl in B ring of the flavones-type compounds such as Que and Myr may increase their affinity to BSA. However, the presence of Zn^2＋ may decrease their binding ability.
出处
《无机化学学报》
SCIE
CAS
CSCD
北大核心
2008年第10期1588-1595,共8页
Chinese Journal of Inorganic Chemistry
基金
江苏省高校自然科学基础研究项目(No.06KJB150120)
国家自然科学基金资助项目(No.20775092)。
关键词
荧光光谱
红外光谱
牛血清蛋白
锌离子
槲皮素
杨梅素
fluorescence spectroscopy
infrared spectroscopy
BSA
zinc（Ⅱ）
quercetin
myricetin
