State Key Laboratory of Food Science and Technology, Nanchang University, No. 235 Nanjing East Road, Nanchang 330047, Jiangxi, China.
Food Chem. 2013 Nov 1;141(1):41-7. doi: 10.1016/j.foodchem.2013.02.122. Epub 2013 Mar 14.
The interaction between sodium benzoate (SB) and calf thymus DNA in simulated physiological buffer (pH 7.4) using acridine orange (AO) dye as a fluorescence probe, was investigated by UV-Vis absorption, fluorescence and circular dichroism (CD) spectroscopy along with DNA melting studies and viscosity measurements. An expanded UV-Vis spectral data matrix was resolved by multivariate curve resolution-alternating least squares (MCR-ALS) approach. The equilibrium concentration profiles and the pure spectra for SB, DNA and DNA-SB complex from the high overlapping composite response were simultaneously obtained. The results indicated that SB could bind to DNA, and hydrophobic interactions and hydrogen bonds played a vital role in the binding process. Moreover, SB was able to quench the fluorescence of DNA-AO complex through a static procedure. The quenching observed was indicative of an intercalative mode of interaction between SB and DNA, which was supported by melting studies, viscosity measurements and CD analysis.
采用吖啶橙（AO）染料作为荧光探针，在模拟生理缓冲液（pH 7.4）中研究了苯甲酸钠（SB）与小牛胸腺 DNA 的相互作用，通过紫外-可见吸收、荧光和圆二色性（CD）光谱以及 DNA 热变性研究和粘度测量进行了研究。通过多元曲线分辨交替最小二乘法（MCR-ALS）方法解析了扩展的紫外-可见光谱数据矩阵。从高重叠的复合响应中同时获得了 SB、DNA 和 DNA-SB 配合物的平衡浓度曲线和纯光谱。结果表明，SB 可以与 DNA 结合，疏水相互作用和氢键在结合过程中起着至关重要的作用。此外，SB 能够通过静态过程猝灭 DNA-AO 复合物的荧光。观察到的猝灭表明 SB 与 DNA 之间存在插入式相互作用模式，这得到了热变性研究、粘度测量和 CD 分析的支持。
