Comparison of different Immobilization Techniques for Thermo stabilization of Laccase enzyme from Trametes versicolor IBL-04

Abstract

Enzyme immobilization utilizing distinctive methodologies and different supports appears to be the most effective possibility for developing industrially compatible enzymes. Immobilization has been discovered as a capable device for enhancing all catalyst properties, specific activity, thermo stability and decreasing inhibition. Laccase with improved catalytic features is a potentially attractive biocatalyst with many possible applications including bioremediation, biomass delignification for (590706) 4.58 Visual comparison of decolorization of dyes with free and immobilized laccase with chitosan bead (a) Sandal-fix Red C4BLN (b) Sandal-fix Golden yellow CRL (300410) 138 4.59 Visual comparison of dye degradation (A) control (B) degradation with free Laccase (C) degradation with laccase immobilized with PVA beads (D) degradation with laccase immobilized with Ca-Alginate beads 140 4.60 Repetitive use of immobilizedlaccase for dye decolorization 142 4.61 Storage stability of free and immobilized Laccase at 16oC 144 ethanol production, chemical synthesis, bio pulping and biosensor development, denim stone washing, cosmetics, dyes degradation, textile finishing and wine stabilization. In this study, four copper containing extracellular laccase was purified from culture filtrate of an indigenous WRF strain Trametes Versicolor IBL-04, grown in solid state fermentation (SSF) under pre optimized condition using corncobs as a substrate. The enzyme was purified (1.00-4.03 fold) to apparent electrophoretic homogeneity through ammonium sulphate precipitation, dialysis, DEAE-cellulose ion exchange and Sephadex G-100 gel exclusion chromatography. The purified enzyme elucidated a monomeric single band on Native and SDS polyacrylamide gel electrophoresis (SDS-PAGE) with an apparent molecular weight of 66 kDa. With an aim to improve its functionalities, the purified laccase was effectively immobilized on nine supporting matrices using diversified immobilization techniques and the relative activity at optimum temperature and pH and thermal stability of free and immobilized laccase were studied for comparative analysis. Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM) were performed to characterize enzyme immobilization. Immobilized laccase was successfully used for the decolorization of six different synthetic (textile) dyes with more than 98% removal rate. The resulted modified laccase enzyme was reusable for up to many cycles in dye color removal and also check the storage stability and thermostability of immobilized laccase. All immobilized parameters showed that immobilized laccase is better for industrial use in comparison to free laccase. Finally results of this study suggested that immobilized laccase catalytic system can be efficiently exploited for dye degradation due to its sustainability, durability and reusability over its soluble counterpart. Keywords: Trametes Versicolor IBL-04, Laccase, purification, characterization, immobilization, dye decolorization