Enzymatic removal of various phenol compounds from artificial wastewater wasundertaken by the combined use of mushroom tyrosinase (EC 1.14.18.1) and chitosanbeads as function of pH value, temperature, tyrosinase dose, and hydrogen peroxide-to-substrate ratio. Chitosan film incubated in a
p-crersol+tyrosinase mixture had themain peaks at 400-470 nm assigned to chemically adsorbed quinone derivatives, whichincreased over the immersion time. These results indicate that removal of phenolcompounds is caused by their tyrosinase-catalyzed oxidation to the correspondingquinone derivatives and the subsequent chemical adsorption on the chitosan film. Theoptimum conditions for quinone adsorption were determined to be pH 7 and 45
C for
p-cresol. Some alkyl-substituted phenol compounds were removed by adsorption ofquinone derivatives enzymatically generated on the chitosan beads, and the % removalfor
p-cresol, 4-ethylphenol, 4-
n-propylphenol, 4-
n-butylphenol, and
p-chlorophenol wentup to 93%. In addition, 4-
tert-butylphenol underwent tyrosinase-catalyzed oxidationin the presence of hydrogen peroxide. This procedure was applicable to removal ofchlorophenols and alkyl-substituted phenols.