abstract
The stability and activity of laccase from Trametes versicolor in two water-soluble ionic liquids (ILs), namely 1-butyl-3-methylimidazolium methyl sulfate, [bmim][MeSO4] and 1,3-dimethylimidazolium methyl sulfate, [mmim][MeSO4], were investigated in this study. Thermal inactivation of laccase was characterized in the presence of these both ILs and as expected first-order kinetics was followed. Inactivation rate constant (k), half-life time (t1/2), and energy of activation (Ea) were determined. Kinetics of 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) oxidation by laccase in the presence of these ILs was studied and MichaelisMenten parameters were calculated. There is no enzymatic inactivation since the maximum reaction rate remained constant for IL concentrations up to 25%, and surprisingly, it was found that laccase was activated for concentrations of 35% of ILs, since the reaction rate increased 1.7 times.
keywords
HORSERADISH-PEROXIDASE; CATALYTIC-ACTIVITY; THERMAL-STABILITY; AQUEOUS-SOLUTIONS; BIOCATALYSIS; STABILIZATION; PERFORMANCE; SOLVENTS; OXIDASE; ACID
subject category
Biotechnology & Applied Microbiology
authors
Tavares, APM; Pereira, JAN; Xavier, AMRB
our authors
Ana Maria Rebelo Barreto Xavier
Assistant Professor
Ana Paula Mora Tavares
Assistant ResearcherGroups
G4 - Renewable Materials and Circular Economy
G5 - Biomimetic, Biological and Living Materials
acknowledgements
This work was funded by FEDER Funds through the Programa Operacional Factores de Competitividade-COMPETE and national funds through FCT-Fundacao para a Ciencia e a Tecnologia under the projects PEst-C/CTM/LA/0011/2011 and PEst-C/EQB/LA0020/2011. A. P. M. Tavares acknowledge the financial support (Programme Ciencia 2008) FCT, Portugal.