Optimization of laccase fermentation and evaluation of kinetic and thermodynamic parameters of a partially purified laccase produced by Daedalea flavida.

TLDR: The production of laccase was optimized by the application of response surface methodology and was 8-fold and 7.5-fold more in static and low-speed shake conditions, respectively, in an optimal medium composition than in an unoptimized medium.

Abstract: Studies on laccase production by Daedalea flavida were carried out in static and low-speed shake cultures. The enzyme production was reduced drastically at a high speed of shaking. Optimal production conditions are necessary to assess the quality of laccase suitable for a specific application. Thus, the production of laccase was optimized by the application of response surface methodology. Laccase production was 8-fold and 7.5-fold more in static and low-speed shake conditions, respectively, in an optimal medium composition than in an unoptimized medium. Laccase obtained using the optimal culture medium of D. flavida was tested for its stability at different temperatures and pH conditions. The partially purified enzyme was most stable at 30°C and pH 5. The half-life of laccase is 87 min at 60°C and at pH 6. The kinetic and thermodynamic parameters were evaluated for the inactivation of the partially purified laccase. The entropy change of inactivation of the enzyme is least at pH 4.