Zhang Shufang, Sun Xuejun, Kong Rongmei, Xu Mingming
College of Chemistry and Chemical Engineering, Qufu Normal University, Shandong, Qufu 273165, People's Republic of China.
College of Chemistry and Chemical Engineering, Qufu Normal University, Shandong, Qufu 273165, People's Republic of China.
Spectrochim Acta A Mol Biomol Spectrosc. 2015 Feb 5;136 Pt C:1666-70. doi: 10.1016/j.saa.2014.10.062. Epub 2014 Oct 24.
The interaction between apigenin and calf thymus deoxyribonucleic acid (ctDNA) in a pH 7.4 Tris-HCl buffer solution was investigated by UV-Vis spectroscopy, fluorescence spectroscopy, DNA melting techniques, and viscosity measurements. It was found that apigenin molecules could intercalate into the base pairs of DNA, forming a apigenin-DNA complex with a binding constant of K310K=6.4×10(4)Lmol(-1). The thermodynamic parameters enthalpy change (ΔH), entropy change (ΔS) and Gibbs free energy (ΔG) were calculated to be 7.36×10(4)Jmol(-1), 329JK(-1)mol(-1) and -2.84×10(4)Jmol(-1) at 310K, respectively. Hydrophobic interaction was the predominant intermolecular force in stabilizing the apigenin-DNA complex. Thermal denaturation study suggested that the stabilization of the ctDNA helix was increased when the apigenin binding to ctDNA as indicated by the increase in thermal denaturation temperature of ctDNA at around 5.0°C in the presence of apigenin. Spectroscopic techniques together with melting techniques and viscosity determination provided evidences of intercalation mode of binding for the interaction between apigenin and ctDNA.
通过紫外可见光谱、荧光光谱、DNA熔解技术和粘度测量等方法，研究了芹菜素与小牛胸腺脱氧核糖核酸（ctDNA）在pH 7.4的Tris-HCl缓冲溶液中的相互作用。结果发现，芹菜素分子能够插入DNA的碱基对之间，形成一种芹菜素-DNA复合物，其结合常数K310K = 6.4×10⁴L·mol⁻¹。在310K时，计算得到的热力学参数焓变（ΔH）、熵变（ΔS）和吉布斯自由能（ΔG）分别为7.36×10⁴J·mol⁻¹、329J·K⁻¹·mol⁻¹和 -2.84×10⁴J·mol⁻¹。疏水相互作用是稳定芹菜素-DNA复合物的主要分子间作用力。热变性研究表明，当芹菜素与ctDNA结合时，ctDNA螺旋的稳定性增加，这表现为在芹菜素存在下ctDNA的热变性温度升高约5.0°C。光谱技术与熔解技术以及粘度测定共同为芹菜素与ctDNA相互作用的插入结合模式提供了证据。
