Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, China West Normal University, Nanchong 637002, China.
J Pharm Biomed Anal. 2012 Jul;66:240-51. doi: 10.1016/j.jpba.2012.03.010. Epub 2012 Mar 15.
In this study, the binding modes of honokiol (HK) and magnolol (MG) with human serum albumin (HSA) have been established under imitated physiological condition, which was very important to understand the pharmacokinetics and toxicity of HK or MG. The experimental results proved that the fluorescence of HSA was quenched by HK or MG through a static quenching procedure. The binding constants of HK-HSA and MG-HSA complexes were 5.304 and 263.755×10(4) L mol(-1) at 298 K, respectively. The binding process was a spontaneous molecular interaction procedure, in which the hydrophobic interaction played a major role in the formation of the HK-HSA complex, whereas, the binding interaction between MG and HSA might involve the hydrophobic interaction strongly and electrostatic interaction. In addition, the effect of HK/MG on the secondary structure of HSA was analyzed using CD, UV-vis absorption, Fourier transform infrared (FT-IR), synchronous fluorescence and three-dimensional fluorescence spectra. According to Förster no-radiation energy transfer theory, the binding distance of HSA to HK or MG was calculated to be 1.842 or 1.238 nm. Besides, the effects of common ions on the binding constants of HSA-HK/MG systems were also discussed.
在这项研究中，在模拟生理条件下建立了厚朴酚（HK）和木兰醇（MG）与人血清白蛋白（HSA）的结合模式，这对于了解 HK 或 MG 的药代动力学和毒性非常重要。实验结果证明，HK 或 MG 通过静态猝灭过程使 HSA 的荧光猝灭。HK-HSA 和 MG-HSA 配合物在 298 K 时的结合常数分别为 5.304 和 263.755×10(4) L mol(-1)。结合过程是一个自发的分子相互作用过程，其中疏水相互作用在 HK-HSA 配合物的形成中起主要作用，而 MG 与 HSA 之间的结合相互作用可能强烈涉及疏水相互作用和静电相互作用。此外，还使用 CD、UV-vis 吸收、傅里叶变换红外（FT-IR）、同步荧光和三维荧光光谱分析了 HK/MG 对 HSA 二级结构的影响。根据福斯特无辐射能量转移理论，计算了 HSA 与 HK 或 MG 的结合距离分别为 1.842 或 1.238nm。此外，还讨论了常见离子对 HSA-HK/MG 体系结合常数的影响。
