1. A comparative study of the purification of betanin
- Author
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Letícia Christina Pires Gonçalves, Vani Xavier Oliveira, Nathana Barbosa Lopes, Erick Leite Bastos, Felipe Augusto Dörr, Monica Teixeira dos Santos, Wilhelm J. Baader, and Marco Aurélio de Souza Trassi
- Subjects
chemistry.chemical_classification ,Chromatography ,E162 ,Ion chromatography ,Betalains ,General Medicine ,Food chemistry ,Beetroot Juice ,High-performance liquid chromatography ,Betanin ,Natural Red 33 ,Analytical Chemistry ,chemistry.chemical_compound ,Colourant ,Column chromatography ,chemistry ,Dextrin ,Betacyanins ,ESPECTROFOTOMETRIA ,Food Science - Abstract
Betanin is a natural pigment with antioxidant properties used as a food colourant. This work describes the spectrophotometric and chromatographic quantification of betanin (2S/15S) and its epimer isobetanin (2S/15R) in fresh beetroot juice, food-grade beetroot powder and betanin standard diluted in dextrin. Absorption spectra of all three samples were deconvoluted using a mixed three-function model. Food-grade beetroot powder has the largest amount of violet-red impurities, probably formed during processing. The purification of betanin from these complex matrices was carried out by seven different methods. Ion exchange chromatography was the most efficient method for the purification of betanin from all samples; however, fractions contain high amounts of salt. Reversed-phase HPLC as well as reversed-phase column chromatography also produced good results at a much faster rate. The longer retention time of isobetanin when compared to betanin in reversed-phase conditions has been investigated by means of quantum-mechanical methods.
- Published
- 2012