title: A comparative study of free and immobilized soybean and horseradish peroxidases for 4-chlorophenol removal: protective effects of immobilization.
abstract: Horseradish peroxidase (HRP) and soybean peroxidase (SBP) were covalently immobilized onto aldehyde glass through their amine groups. The activity yield and the protein content for the immobilized SBP were higher than for the immobilized HRP. When free and immobilized peroxidases were tested for their ability to remove 4-chlorophenol from aqueous solutions, the removal percentages were higher with immobilized HRP than with free HRP, whereas immobilized SBP needs more enzyme to reach the same conversion than free enzyme. In the present paper the two immobilized derivatives are compared. It was found that at an immobilized enzyme concentration in the reactor of 15 mg l(-1), SBP removed 5% more of 4-chlorophenol than HRP, and that a shorter treatment was necessary. Since immobilized SBP was less susceptible to inactivation than HRP and provided higher 4-chlorophenol elimination, this derivative was chosen for further inactivation studies. The protective effect of the immobilization against the enzyme inactivation by hydrogen peroxide was demonstrated.
authors.affiliation: Chemical Engineering Department, University of Murcia, Campus de Espinardo, Murcia, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Bódalo
authors.forename: Josefa
authors.initials: J
authors.lastname: Bastida
authors.forename: M Fuensanta
authors.initials: MF
authors.lastname: Máximo
authors.forename: M Claudia
authors.initials: MC
authors.lastname: Montiel
authors.forename: María
authors.initials: M
authors.lastname: Gómez
authors.forename: M Dolores
authors.initials: MD
authors.lastname: Murcia
mesh_terms: D001671:Biochemistry / Q000379:methods*; D019149:Bioreactors; D002733:Chlorophenols / Q000737:chemistry*; D004789:Enzyme Activation; D004798:Enzymes / Q000737:chemistry; D004800:Enzymes, Immobilized / Q000737:chemistry*; D005898:Glass; D006735:Horseradish Peroxidase / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D009195:Peroxidase / Q000737:chemistry*; D010544:Peroxidases / Q000737:chemistry; D016062:Porosity; D013025:Glycine max / Q000201:enzymology*
chemical_list: D002733:Chlorophenols; D004798:Enzymes; D004800:Enzymes, Immobilized; C029107:4-chlorophenol; D006861:Hydrogen Peroxide; D006735:Horseradish Peroxidase; D010544:Peroxidases; D009195:Peroxidase