Peptidolytic microbial community of methanogenic reactors from two modified UASBs of brewery industries

Revista de microbiologia

Baena, S.¹  Díaz, C.²  Patel, B.K.C.³ 

[1] Griffith University, Brisbane, Australia;Pontificia Universidad Javeriana, Bogotá, Colombia;Universités de Provence et de la Méditerranée, France

关键词: anaerobic peptide-degrading bacteria;    MPN;    UASB;    16S rRNA gene.;   

DOI  :  10.1590/S1517-83822010000300022

学科分类：农业科学（综合）

来源: Sociedade Brasileira de Microbiologia / Brazilian Society for Microbiology

【 摘 要 】

We studied the peptide-degrading anaerobic communities of methanogenic reactors from two mesophilic full-scale modified upflow anaerobic sludge blanket (UASB) reactors treating brewery wastewater in Colombia. Most probable number (MPN) counts varied between 7.1 x 108 and 6.6 x 109 bacteria/g volatile suspended solids VSS (Methanogenic Reactor 1) and 7.2 x 106 and 6.4 x 107 bacteria/g (VSS) (Methanogenic Reactor 2). Metabolites detected in the highest positive MPN dilutions in both reactors were mostly acetate, propionate, isovalerate and, in some cases, negligible concentrations of butyrate. Using the highest positive dilutions of MPN counts, 50 dominant strains were isolated from both reactors, and 12 strains were selected for sequencing their 16S rRNA gene based on their phenotypic characteristics. The small-subunit rRNA gene sequences indicated that these strains were affiliated to the families Propionibacteriaceae, Clostridiaceae and Syntrophomonadaceae in the low G + C gram-positive group and Desulfovibrio spp. in the class d-Proteobacteria. The main metabolites detected in the highest positive dilutions of MPN and the presence of Syntrophomonadaceae indicate the effect of the syntrophic associations on the bioconversion of these substrates in methanogenic reactors. Additionally, the potential utilization of external electron acceptors for the complete degradation of amino acids by Clostridium strains confirms the relevance of these acceptors in the transformation of peptides and amino acids in these systems.

【 授权许可】

CC BY-NC