Biodegradation of brominated aromatics by cultures and laccase of Trametes versicolor.

Abstract 2-Bromophenol ( 1 ), 4-bromophenol ( 2 ), 2,4-dibromophenol ( 3 ), 2,6-dibromophenol ( 4 ), 2,4,6-tribromophenol ( 5 ) and tetrabromobisphenol A ( 6 ) (1 mM each) added to growing submerged cultures of Trametes versicolor CCBAS 612 were eliminated by 65–85% from the culture medium within 4 d. Extracellular laccase activity in the culture medium was influenced by the type of brominated compound added. Maximum level of laccase (63 U L −1 ) was found in the culture with 2-bromophenol. Tetrabromobisphenol A was degraded by a commercial laccase from Trametes versicolor in absence of any oxidation mediator, hydroxylated dibrominated compounds being detected as soluble reaction products by LC/MS. A significant degradation of brominated phenols by laccase was achieved only in the presence of ABTS structural characterization of major products suggesting reaction between bromophenol and ABTS radicals.