title: Recalcitrance as a catalyst for new developments.
abstract: Humic substances are very recalcitrant in anaerobic environments as substrates, mostly due to their non-hydrolyzable high molecular weight structure, which is incompatible for cell uptake. The recalcitrant nature can be applied towards immobilizing pollutants into non-toxic humic substances. Certain anaerobic bioconversions such as demethylation of lignin and reduction of nitro- or azo groups can activate pollutants for humification processes upon subsequent exposure to air. Although humic substances provide no carbon or energy for microorganisms, the evidence presented here indicates that they are very active as terminal electron acceptors and redox mediators promoting the anaerobic degradation and biotransformation of priority pollutants.
authors.affiliation: Department of Chemical and Environmental Engineering, University of Arizona, Tucson 85721-0011, USA.
authors.forename: J A
authors.initials: JA
authors.lastname: Field
mesh_terms: D001421:Bacteria, Anaerobic; D001673:Biodegradation, Environmental; D019149:Bioreactors; D006812:Humic Substances; D008031:Lignin / Q000378:metabolism; D010084:Oxidation-Reduction; D014865:Waste Disposal, Fluid / Q000379:methods*
chemical_list: D006812:Humic Substances; D008031:Lignin