Caracterización de la lacasa de "Streptomyces cyaneus" CECT 3335 y aproximación al estudio de su potencial oxidativo y función biológica

  1. MOYA LOBO, RAQUEL
unter der Leitung von:
  1. María Enriqueta Arias Fernández Doktorvater/Doktormutter
  2. Manuel Pascual Hernández Cutuli Co-Doktorvater/Doktormutter

Universität der Verteidigung: Universidad de Alcalá

Fecha de defensa: 30 von September von 2011

Gericht:
  1. José Antonio Salas Fernández Präsident/in
  2. Juana Rodríguez Bullido Sekretär/in
  3. Ramón Santamaría Sánchez Vocal
  4. María Isabel Pérez Leblic Vocal
  5. Francisco Ignacio Javier Pastor Blasco Vocal

Art: Dissertation

Zusammenfassung

The ability of a laccase (EC 1.10.3.2) produced by Streptomyces cyaneus CECT 3335 to decolourise and detoxify azo dyes was assessed. Results showed that a colour loss of 90% was achieved only in the presence of acetosyringone (0.1 mM) acting as a redox mediator for the laccase. Toxicological analysis of the decolourised dyes revealed that there was no direct correlation between decolouration and detoxification; in fact, in the case of the dyes Methyl Orange and Orange II, a significant increase in toxicity was produced after the treatment. In contrast, a significant decrease in toxicity was observed after the decolouration of New Coccine and Chromotrope 2R. Finally, HPLC analysis of the dyes after treatment revealed the complete disappearance of both dyes and mediator and a concomitant appearance of new chromatographic peaks which could be responsible of the residual toxicity detected in some cases.