Application of molecular techniques to evaluate the methanogenic archaea and anaerobic bacteria in the presence of oxygen with different COD : sulfate ratios in a UASB reactor

Autor(es)

Hirasawa, Julia Sumiko ^[1] ; Sarti, Arnaldo ^[1] ; Saavedra Del Aguila, Nora Katia ^[1] ; Varesche, Maria Bernadete A. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo EESC USP, Escola Engn Sao Carlos, Dept Hidraul & Saneamento, Lab Proc Biol, BR-13563120 Sao Carlos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Anaerobe; v. 14, n. 4, p. 209-218, OCT 2008.
• Citações Web of Science: 27

Resumo

In this paper, the microbial characteristics of the granular sludge in the presence of oxygen (3.0 +/- 0.7 mg O-2 1(-1)) were analyzed using molecular biology techniques. The granules were provided by an upflow anaerobic sludge blanket (UASB) operated over 469 days and fed with synthetic substrate. Ethanol and sulfate were added to obtain different COD/SO42- ratios (3.0, 2.0, and 1.6). The results of fluorescent in situ hybridization (FISH) analyses showed that archaeal cells, detected by the ARC915 probe, accounted for 77%, 84%, and 75% in the COD/SO42- ratios (3.0, 2.0, and 1.6, respectively). Methanosaeta sp. was the predominant acetoclastic archaea observed by optical microscopy and FISH analyses, and confirmed by sequencing of the excised bands of the DGGE gel with a similarity of 96%. The sulfate-reducing bacterium Desulfovibrio vulgaris subsp. vulgaris (similarity of 99%) was verified by sequencing of the DGGE band. Others identified microorganism were similar to Shewanella sp. and Desulfitobacterium hafniense, with similarities of 95% and 99%, respectively. These results confirmed that the presence of oxygen did not severely affect the metabolism of microorganisms that are commonly considered strictly anaerobic. We obtained mean efficiencies of organic matter conversion and sulfate reducing higher than 74%. (C) 2008 Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 02/12985-7 - Avaliacao da metanogenese e sulfetogenese na presenca de oxigenio, sob diferentes relacoes etanol/sulfato, utilizando tecnicas de biologia molecular.
• Beneficiário: Julia Sumiko Hirasawa
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 01/05489-0 - Desenvolvimento, análise, aprimoramento e otimização de reatores anaeróbios para tratamento de águas residuárias
• Beneficiário: Eugenio Foresti
• Modalidade de apoio: Auxílio à Pesquisa - Temático