title: Immobilization of tyrosinase on chitosan-clay composite beads.
abstract: Tyrosinase was immobilized on glutaraldehyde crosslinked chitosan-clay composite beads and used for phenol removal. Immobilization yield, loading efficiency and activity of tyrosinase immobilized beads were found as 67%, 25% and 1400 U/g beads respectively. Optimum pH of the free and immobilized enzyme was found as pH 7.0. Optimum temperature of the free and immobilized enzyme was determined as 25-30 °C and 25 °C respectively. The kinetic parameters of free and immobilized tyrosinase were calculated using l-catechol as a substrate and K(m) value for free and immobilized tyrosinase were found as 0.93 mM and 1.7 mM respectively. After seven times of repeated tests, each over 150 min, the efficiency of phenol removal using same immobilized tyrosinase beads were decreased to 43%.
authors.affiliation: Celal Bayar University, Faculty of Science and Arts, Chemistry Department, 45300 Muradiye, Manisa, Turkey. ayse.dincer@bayar.edu.tr
authors.forename: Ayşe
authors.initials: A
authors.lastname: Dinçer
authors.forename: Seda
authors.initials: S
authors.lastname: Becerik
authors.forename: Tülin
authors.initials: T
authors.lastname: Aydemir
mesh_terms: D000363:Agaricales / Q000201:enzymology; D000538:Aluminum Silicates / Q000737:chemistry*; D048271:Chitosan / Q000737:chemistry*; D000077215:Clay; D004800:Enzymes, Immobilized / Q000737:chemistry* / Q000378:metabolism; D005976:Glutaral / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008863:Microspheres; D014442:Monophenol Monooxygenase / Q000737:chemistry* / Q000378:metabolism; D019800:Phenol / Q000737:chemistry / Q000302:isolation & purification; D013696:Temperature; D018505:Waste Management
chemical_list: D000538:Aluminum Silicates; D004800:Enzymes, Immobilized; D019800:Phenol; D048271:Chitosan; D014442:Monophenol Monooxygenase; D000077215:Clay; D005976:Glutaral