Table of Contents
ISRN Biotechnology
Volume 2013, Article ID 968241, 12 pages
http://dx.doi.org/10.5402/2013/968241
Research Article

Elimination of Bisphenol A and Triclosan Using the Enzymatic System of Autochthonous Colombian Forest Fungi

1Biopolymers Group, Faculty of pharmaceutical Chemistry, University of Antioquia, Calle 67 No. 53-108, Antioquia, Colombia
2Laboratory of Microbial Physiology and Ecology, Faculty of Sciences, Université Libre de Bruxelles, Institut de Santé Publique, rue Engeland 642, 1180 Brussels, Belgium
3Unit of Bioengineering, Université Catholique de Louvain, Croix du Sud 2, 1348 Louvain-la-Neuve, Belgium
4Department of Chemical Engineering, Université de Sherbrooke, 2500 boulevard de l’Université, Sherbrooke, QC, Canada J1K 2R1
5Department of Civil Engineering, Université de Sherbrooke, 2500 boulevard de l'Université, Sherbrooke, QC, Canada J1K 2R1
6Group of Taxonomy and Ecology of Colombian Fungi, Institute of Biology, University of Antioquia, Calle 67 No. 53-108, Antioquia, Colombia

Received 24 April 2012; Accepted 31 May 2012

Academic Editors: E. Formentin, C. D. Murphy, J.-C. Sigoillot, and F. Tao

Copyright © 2013 Carolina Arboleda et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Bisphenol A (BPA) and triclosan (TCS) are known or suspected potential endocrine disrupting chemicals (EDCs) which may pose a risk to human health and have an environmental impact. Enzyme preparations containing mainly laccases, obtained from Ganoderma stipitatum and Lentinus swartzii, two autochthonous Colombian forest white rot fungi (WRF), previously identified as high enzyme producers, were used to remove BPA and TCS from aqueous solutions. A Box-Behnken factorial design showed that pH, temperature, and duration of treatment were significant model terms for the elimination of BPA and TCS. Our results demonstrated that these EDCs were extensively removed from 5 mg L−1 solutions after a contact time of 6 hours. Ninety-four percent of TCS and 97.8% of BPA were removed with the enzyme solution from G. stipitatum; 83.2% of TCS and 88.2% of BPA were removed with the L. swartzii enzyme solution. After a 6-hour treatment with enzymes from G. stipitatum and L. swartzii, up to 90% of the estrogenic activity of BPA was lost, as shown by the yeast estrogen screen assay. 2,2-Azino-bis-(3-ethylthiazoline-6-sulfonate) (ABTS) was used as a mediator (laccase/mediator system) and significantly improved the laccase catalyzed elimination of BPA and TCS. The elimination of BPA in the absence of a mediator resulted in production of oligomers of molecular weights of 454, 680, and 906 amu as determined by mass spectra analysis. The elimination of TCS in the same conditions produced dimers, trimers, and tetramers of molecular weights of 574, 859, and 1146 amu. Ecotoxicological studies using Daphnia pulex to determine lethal concentration (LC50) showed an important reduction of the toxicity of BPA and TCS solutions after enzymatic treatments. Use of laccases emerges thus as a key alternative in the development of innovative wastewater treatment technologies. Moreover, the exploitation of local biodiversity appears as a potentially promising approach for identifying new efficient strains for biotechnological applications.