Characterization of erythrosine B binding to bovine serum albumin and bilirubin displacement
Document Type
Article
Publication Date
1-1-2008
Abstract
The interaction of erythrosine 13 (ErB), a commonly used dye for coloring foods and drinks, with bovine serum albumin (BSA) was investigated both in the absence and presence of bilirubin (BR) using absorption and absorption difference spectroscopy. ErB binding to BSA was reflected from a significant red shift of 11 nm in the absorption maximum of ErB (527 um) with the change in absorbance at λmax. Analysis of absorption difference spectroscopic titration results of BSA with increasing concentrations of ErB using Benesi-Hildebrand equation gave the association constant, K as 6.9 × 104 M-1. BR displacing action of ErB was revealed by a significant blue shift in the absorption maximum, accompanied by a decrease in absorbance difference at λmax in the difference spectrum of BR-BSA complex upon addition of increasing concentrations of ErB. This was further substantiated by fluorescence spectroscopy, as addition of increasing concentrations of ErB to BR-BSA complex caused a significant decrease in fluorescence at 510 nm. The results suggest that ErB binds to a site in the vicinity of BR binding site on BSA. Therefore, intake of ErB may increase the risk of hyperbilirubinemia in the healthy subjects.
Keywords
Absorption spectroscopy, Bilirubin displacement, Bovine serum albumin, Erylhrosine B
Divisions
InstituteofBiologicalSciences
Publication Title
Indian Journal of Biochemistry & Biophysics
Volume
46
Issue
4
Publisher
National Institute of Science Communication and Information Resources, CSIR