title: Spectroscopic studies on the interaction of sodium benzoate, a food preservative, with calf thymus DNA.
abstract: 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.
authors.affiliation: State Key Laboratory of Food Science and Technology, Nanchang University, No. 235 Nanjing East Road, Nanchang 330047, Jiangxi, China. gwzhang@ncu.edu.cn
authors.forename: Guowen
authors.initials: G
authors.lastname: Zhang
authors.forename: Yadi
authors.initials: Y
authors.lastname: Ma
mesh_terms: D000165:Acridine Orange; D000818:Animals; D002417:Cattle; D002942:Circular Dichroism; D004247:DNA / Q000737:chemistry*; D005456:Fluorescent Dyes / Q000737:chemistry; D005520:Food Preservatives / Q000737:chemistry*; D007700:Kinetics; D020160:Sodium Benzoate / Q000737:chemistry*; D013057:Spectrum Analysis
chemical_list: D005456:Fluorescent Dyes; D005520:Food Preservatives; D004247:DNA; C427203:calf thymus DNA; D000165:Acridine Orange; D020160:Sodium Benzoate