title: Degradation of phenol using tyrosinase immobilized on siliceous supports.
abstract: The degradation of phenol by tyrosinase immobilized on chemically modified sodium aluminosilicate (NaA), calcium aluminosilicate (CaA), and silica gel was studied. Phenol conversion by immobilized tyrosinase ranged between approximately 15% and 60%, depending upon the initial phenol concentration, pH, and enzyme loading. Tyrosinase immobilized on CaA and on NaA could be re-used repeatedly without any decrease in performance. However, in studies at pH 8.0, significant enzyme inhibition was observed, since phenol conversion was rapid for approximately 20 min, then reached a plateau. The inhibition was reversible; activity was restored upon placing the immobilized enzyme in fresh substrate. Reducing the pH to 6.8 from 8.0 led to higher conversion of phenol, and decreased the inhibition of the immobilized enzyme.
authors.affiliation: Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto, Ont., Canada M5S 3E5.
authors.forename: Gayathri B
authors.initials: GB
authors.lastname: Seetharam
authors.forename: Bradley A
authors.initials: BA
authors.lastname: Saville
mesh_terms: D000538:Aluminum Silicates / Q000737:chemistry; D004202:Disinfectants / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste; D014442:Monophenol Monooxygenase / Q000737:chemistry / Q000494:pharmacology*; D019800:Phenol / Q000378:metabolism*; D058428:Silica Gel; D012822:Silicon Dioxide / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000378:metabolism*; D018508:Water Purification / Q000379:methods*
chemical_list: D000538:Aluminum Silicates; D004202:Disinfectants; D007220:Industrial Waste; D014874:Water Pollutants, Chemical; C049037:aluminosilicate; D019800:Phenol; D058428:Silica Gel; D012822:Silicon Dioxide; D014442:Monophenol Monooxygenase