Immobilization strategies for laccase from Trametes versicolor on mesostructured silica materials and the application to the degradation of naphthalene

The oxidation of naphthalene by immobilized laccase from Trametes versicolor has been performed using diverse immobilization strategies on mesostructured silica materials. Laccase was immobilized by physical adsorption on several SBA-15 with different textural properties and by covalent attachment on functionalized SBA-15 prepared by co-condensation method (direct synthesis). The adsorption of laccase was partially reversible and showed some degree of lixiviation. However, covalently attached laccase to aminopropyl and aminobutyl functionalized SBA-15 exhibited important activity for the degradation of naphthalene with, respectively, 35% and 39%wt of removal in 5 h. The aminopropyl biocatalyst retained higher activity after repeated uses than the corresponding aminobutyl.