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

  1. MOYA LOBO, RAQUEL
Supervised by:
  1. María Enriqueta Arias Fernández Director
  2. Manuel Pascual Hernández Cutuli Co-director

Defence university: Universidad de Alcalá

Fecha de defensa: 30 September 2011

Committee:
  1. José Antonio Salas Fernández Chair
  2. Juana Rodríguez Bullido Secretary
  3. Ramón Santamaría Sánchez Committee member
  4. María Isabel Pérez Leblic Committee member
  5. Francisco Ignacio Javier Pastor Blasco Committee member

Type: Thesis

Teseo: 315571 DIALNET lock_opene_Buah editor

Abstract

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.