Bertolino, Sueli MouraRodrigues, Isabel Cristina BragaCota, Renata Guerra de SáAquino, Sergio Francisco deLeão, Versiane Albis2015-03-062015-03-062012BERTOLINO, S. M. et al. Implications of volatile fatty acid profile on the metabolic pathway during continuous sulfate reduction. Journal of Environmental Management, v. 103, p. 15-23, 2012. Disponível em: <http://www.sciencedirect.com/science/article/pii/S0301479712000916>. Acesso em: 08 nov. 2014.0301-4797http://www.repositorio.ufop.br/handle/123456789/4560Volatile fatty acid (VFA) profile is an important parameter in anaerobic reactors because it enables the assessment of metabolic pathways. Volatile fatty acids were monitored during sulfate reduction in a UASB (upflow anaerobic sludge blanket) reactor treating 2 g/L sulfate concentration and with the organic loading increasing from 3.5 kg COD/m3 d to 5.9 kg COD/m3 d, for a 1-day residence time. In the absence of recirculation, the best outcome (65% reduction) was noticed with the lowest organic loading (3.55 kg/m3 d). When recirculation was applied, sulfate reduction yields increased to 89%, corresponding to a sulfate removal rate of 1.94 kg SO4 2_/m3 d. The reactor performance was discussed in relation to microbial diversity and metabolic pathways. At high organic loading, two metabolic pathways account for lactate degradation: (i) lactate is oxidized to acetate and carbon dioxide by the incomplete-oxidizer SRB (sulfate-reducing bacteria) Desulfomonas, Desulfovibrio, Desulfolobus, Desulfobulbus and Desulfotomaculum spp.; (ii) lactate is converted to acetate by fermenting bacteria such as Clostridium sp. High propionate concentrations imply that there are low sulfate reduction efficiencies.en-USSulfate reductionLactatePropionateFermentationMetabolic pathwaysArtigo publicado em periodicoO periódico Journal of Environmental Management concede permissão para depósito deste artigo no Repositório Institucional da UFOP. Número da licença: 3547700070746.https://doi.org/10.1016/j.jenvman.2012.02.022