食品抗氧化剂4-己基间苯二酚与DNA分子结合模式检测

Detection of Binding Mode Between Food Antioxidant of 4-hexylresorcinol and Calf Thymus DNA

应用荧光光谱法、圆二色谱法(CD)并结合熔点及黏度测量方法,研究了生理酸度条件下(pH 7.4),食品抗氧化剂4-己基间苯二酚(4-HR)与小牛胸腺DNA的分子结合模式。结果显示:4-HR能与吖啶橙(AO)竞争结合DNA的位点,4-HR的存在增加了DNA的熔点和黏度,降低了KI的荧光猝灭效应,表明4-HR与DNA以嵌插模式结合。CD结果揭示,4-HR的嵌入诱导DNA的构象由B型向A型转变。计算出的热力学参数表明,氢键与范德华力是4-HR与DNA作用的主要驱动力。

Interaction mode of 4 -hexylresorcinol （4 -HR） with calf thymus DNA in physiological buffer （pH 7.4） was determined by fluorescence and circular dichroism spectroscopy, coupled with melting experiments and viscosity measurements. The results showed that 4 - HR was able to compete with acridine orange （AO） binding to DNA,increase the melting temperature and viscosity of DNA, and decrease iodide quenching effect,indicating that 4 - HR intercalated into the base pairs of DNA. Changes in CD spectra provided evidence that a B - DNA to A - DNA transformation occurred upon the binding of 4 -HR. Moreover, it can be concluded that Hydrogen bonds and van der Waals force played a main role in the binding of 4 - HR to DNA according to the calculated thermodynamic parameters.