Halogenated pesticide transformation by a laccase-mediator system.

Full Abstract

The transformation of organic halogenated pesticides by laccase-mediator system has been investigated. Twelve pesticides were assayed in the presence of nine different mediators. Acetosyringone and syringaldehyde showed to be the best mediators. The halogenated pesticides bromoxynil, niclosamide, bromofenoxim and dichlorophen were transformed by the laccase-syringaldehyde system showing catalytic activities of 48.8, 142.0, 166.2 and 1257.6nmolmin(-1)U(-1), respectively. The highest pesticide transformation rates were obtained with a mediator-substrate proportion of 5:1, one of the lowest reported so far for the laccase-mediator systems. The analysis of the main product from the dichlorophen transformation showed that an oxidative dehalogenation is involved in the catalytic mechanism. Adduct formation between the mediator syringaldehyde and the pesticides dichlorophen or bromoxynil was also found after enzymatic oxidation. The main goal of this work is to evaluate environmental-friendly mediators for the pesticide transformation, and the potential of laccase-mediator system to efficiently reduce the environmental impact of organic halogenated pesticides is discussed.

Author information

Author/s: Torres-Duarte, Cristina (C); Roman, Rosa (R); Tinoco, Raunel (R); Vazquez-Duhalt, Rafael (R);

Affiliation: Instituto de Biotecnología, Universidad Nacional Autónoma de México, Av. Universidad 2001, Cuernavaca, Morelos 62210, Mexico.

Journal and publication information

Publication Type: Journal Article; Research Support, Non-U.S. Gov't

Journal: Chemosphere (Chemosphere), published in England. (Language: eng)

Reference: 2009-Oct; vol 77 (issue 5) : pp 687-92

Dates: Created 2009/10/05; Completed 2009/11/17;

PMID: 19695672, status: MEDLINE (last retrieved date: 11/17/2009)

Sourced from the National Library of Medicine. Abstract text and other information may be subject to copyright.

External Links for this article
(including full text providers, if available):

Click Electronic Full-text Provider Links to see options for finding the electronic full text links to this article. Note there may be a subscription or fee required for access to the full text. See our FAQ for information on finding FREE full text articles.

This article may also be located in paper journal collections available in many libraries. Use the Journal and Publication Information above to find the full article.

MeSH headings (categories)

This article was linked to the MeSH Headings (categories) shown below.

Note: Bold headings indicate primary MeSH headings or qualifiers.

Associated Chemicals: Benzaldehydes (0) ; Nitriles (0) ; Oximes (0) ; Pesticides (0) ; bromofenoxim (0) ; syringaldehyde (134-96-3) ; bromoxynil (1689-84-5) ; Niclosamide (50-65-7) ; Dichlorophen (97-23-4) ; Laccase (EC 1.10.3.2)

These are the most related articles currently in our database: