QUANTIFICATION OF POLYMERISATION PROCESSES DURING THE OXIDATIVE DEGRADATION OF 14C-LABELLED CHLOROPHENOLS


    loading  Checking for direct PDF access through Ovid

Abstract

In experiments employing the lignocellulose-decaying basidiomycetes Trametes versicolor and Stropharia rugosoannulata degrading uniformly 14C-labelled 2,4-dichlorophenol and pentachlorophenol, a combination of size exclusion chromatography (SEC), fractionation, and β-scintillation counting was applied to quantify polymerisation products formed during chlorophenol degradation. Time-dependent mass balances were generated by analysis of 14C in polymerisation products, CO2, as well as monomer non-polar and polar metabolites. Approximately 30% of the chlorophenols were found to be polymerised. A major fraction of the polymerised products corresponded to a molecular weight range from 0.24–40 kDa. Only a minor fraction could be attributed to a molecular weight >40 kDa. This method proved to be useful in quantification of polymerisation products and kinetics of the polymerisation processes, whereas UV/Vis detection of polymerisation products separated by SEC led to false positive results. The SEC-14C method could also be applied for other complex processes where polymerisation or depolymerisation occurs (humification, degradation of lignocellulose, formation of bound residues from xenobiotics such as polycyclic aromatic hydrocarbons or 2,4,6-trinitrotoluene) and where spectrophotometric determinations are difficult or impossible.

    loading  Loading Related Articles