Biodegradation of bisphenol A and its metabolic intermediates by activated sludge: Stoichiometry and kinetics analysis

Abstract

Bisphenol A (BPA) has been described as a estrogenic compound. However, it is used in the production of polycarbonate, epoxy resins and other plastics. Mixed microbial cultures, such as activated sludge, have been proposed as a feasible methodology to achieve the decontamination of wastewater containing BPA. Several studies on the biodegradation of BPA have demonstrated the presence of 4-hydroxyacetophenone (4HAP), 4-hydroxybenzaldehyde (4HB) and 4-hydroxybenzoic acid (A4HB) as the main metabolic intermediates. The objective of the present work was to study the kinetics and stoichiometric characteristics of the aerobic degradation of BPA and its metabolic intermediates by activated sludge. The effect of the sludge age (SA), and the concentration of each compound was analyzed. The biodegradation of the compounds was analyzed by an open respirometer. The kinetics of the biodegradation of all the tested compounds was influenced by the SA, the acclimation process, and the concentration of the tested compound. The stoichiometry of the reactions was not affected by the studied conditions. The oxidation coefficient (YO/S) was 10.0 ± 0.5, 5.2 ± 0.2, 3.7 ± 0.2, and 3.0 ± 0.1 molO2 molS-1 for BPA, 4HAP, 4HB, and 4HBA, respectively. Based on the obtained YO/S values, the aerobic biodegradation pathway of the tested compounds by BPA-acclimated activated sludge is discussed.Fil: Ferro Orozco, Ana Micaela. Universidad Nacional de Mar del Plata. Facultad de Ingeniería; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Contreras, Edgardo Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería; ArgentinaFil: Zaritzky, Noemi Elisabet. Universidad Nacional de La Plata. Facultad de Ingenieria; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentin