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 degrees C, which was improved to pH 6 and 70 degrees C in PVA-alginate immobilized biocatalyst. PVA-alginate immobilized laccase presented comparatively high V-max (from 720 to 962 U/mL) and low K-m (from 70 to 12 mu M) 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.