Photophysics and hydrolytic stability of betalains in aqueous trifluoroethanol

  title={Photophysics and hydrolytic stability of betalains in aqueous trifluoroethanol},
  author={Fernando Heering Bartoloni and Leticia Christina Pires Gonçalves and Ana Clara Beltran Rodrigues and Felipe A. D{\"o}rr and Ernani Pinto and Erick Leite Bastos},
  journal={Monatshefte f{\"u}r Chemie - Chemical Monthly},
Betalains are natural antioxidant pigments responsible for the visible fluorescence of flowers. Although these compounds are almost exclusively soluble in water, they are very sensitive to both hydrolysis and water-catalyzed isomerization. We show that three representative betalains are soluble in 2,2,2-trifluoroethanol (TFE) and that the hydrolytic stability of these model compounds in hydroalcoholic solutions increases with increasing amount of TFE. Furthermore, TFE increases the fluorescence… 

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