Poly(vinyl Alcohol)-Alginate Immobilized Trametes versicolor IBL-04 Laccase as Eco-friendly Biocatalyst for Dyes Degradation

Laccase-based biocatalysts are promising agents for the remediation of environmental pollutants. However, stability, reusability, and cost-effectiveness remain a challenge for biochemical engineering. Herein, Trametes versicolor IBL-04 laccase was immobilized on poly(vinyl alcohol) (PVA)-alginate beads. The maximum immobilization efficiency was observed using a 2.5 mm bead size with 12% (w/v) PVA and 2% (w/v) alginate concentration. The native enzyme displayed optimal activity at pH 5.0, and 45 °C, which was improved to pH 6 and 70 °C in PVA-alginate immobilized biocatalyst. PVA-alginate immobilized laccase presented comparatively high Vmax (from 720 to 962 U/mL) and low Km (from 70 to 12 µM) values from the native enzyme. Immobilized laccase was applied to catalyze the decolorization of various textile dye pollutants, including Rhodamine B, Reactive Black 5 (RB5), Drimaren Red and Drimaren Turquoise. Results revealed almost complete decolorization and decomposition of all dye’s solution by the laccase-assisted biocatalytic reaction. Prominent peaks of untreated dyes observed in the visible region disappeared following enzymatic treatment, and the appearance of any new peaks was not detected during the enzyme-mediated degradation process. In conclusion, immobilizing laccase on PVA-alginate matrix offers a facile and cost-efficient approach to remediate dyes and exhibit considerable potential for numerous biochemical engineering applications.