Characterization of Active Microbes in a Full-Scale Anaerobic Fluidized Bed Reactor Treating Phenolic Wastewater

Abstract

This study investigated the active microbial community in a full-scale granular activated carbon-anaerobic fluidized bed (GAC-AFB) reactor treating wastewater from the manufacturing of phenolic resin, using 16S rRNA-based molecular analyses. The results of cDNA from 16S rRNA revealed that Methanosaeta-related (83.9% of archaeal clones) and Syntrophorhabdaceae (formerly named Deltaproteobacteria group TA)-related (68.9% of bacterial clones) microorganisms were as the most predominant populations in the phenol-degrading GAC-AFB reactor. The high abundance of Syntrophorhabdaceae was supported by a terminal restriction fragment length polymorphism (T-RFLP) analysis, which showed that a Syntrophorhabdaceae-like fragment of 119 bp (~80% of total fragments) was the most predominant phylotype. Furthermore, fluorescence in situ hybridization (FISH) analyses suggested that Syntrophusand Chloroflexi-like cells were also in high abundance in the GAC biofilm. A non-layered structure of microorganisms was found in the GAC biofilm, where Methanosaeta (thick filamentous), Syntrophorhabdaceae (oval-shaped), Syntrophus (small rods) and Chloroflexi (thin-filamentous) were randomly distributed with high abundance. These findings greatly improve our understanding of the diversity and distribution of microbial populations in a full-scale mesophilic bioreactor treating an actual phenol-containing waste stream.Key words: phenol, anaerobic, microbial, phylogenetic, FISH Syntrophic association is an important process in anaerobic catabolism, whereby two or more microorganisms cooperate closely to completely degrade a substance neither can degrade alone. This process generally requires interaction between fermentative bacteria and methanogenic archaea (methanogens) to overcome the thermodynamic barrier in the initial step of degradation (e.g., fatty acids, solvents and aromatic substrates), and leads to the production of methane. Biodegradation of phenol under methanogenic conditions has been known for more than two decades (42, 48), and a number of different anaerobic processes (23,37,40,42) have been developed to successfully treat industrial waste streams containing phenol. A bottleneck to the starting up of these anaerobic processes was considered to be the cultivation/ acclimation of unique microbial specialists. A few reports have characterized these syntrophic phenol-degrading microorganisms. Fang and co-workers (16, 49) suggested that Desulfotomaculum, Clostridium and Syntrophus, together with Methanosaetaceae, Methanomicrobiales and Methanobacteriaceae, were the predominant microbial populations in a laboratory-scale upflow anaerobic sludge bed (UASB) reactor that degraded phenol under ambient temperature (26°C). Last year, we reported that Deltaproteobacteria group TA-and Pelotomaculum-related populations were the most important fermentative bacteria, in phenol-degrading enrichments under mesophilic (37°C) and thermophilic (55°C) conditions, respectively (9). More recently, a syntrophic phenol-degrading bacterium (Syntrophorhabd...

Use of a Hierarchical Oligonucleotide Primer Extension Approach for Multiplexed Relative Abundance Analysis of Methanogens in Anaerobic Digestion Systems

“…5). These findings were in high accordance with those from several previous studies (25,28,(35)(36)(37). The dominance of the Methanosaeta population indicated its success within the niche for the production of methane from acetate, a common constituent in industrial wastewater (23) as well as a central metabolite resulting from the anaerobic fermentation of substances.…”

The nexus of syntrophy‐associated microbiota in anaerobic digestion revealed by long‐term enrichment and community survey

“…These syntrophs could interact with methanogens and formed core syntrophic sub-communities responsible to degrade PR (i.e., Syntrophobacter), BT (i.e, Syntrophomonas) and aromatics (i.e., Syntrophus and Pelotomaculum). Based on the occurrence of these syntrophs in different AD by substrate type, it can be inferred that syntrophic PR degradation may support AD-treating brewery wastewater (Werner et al, 2011), municipal sewage sludge (Riviere et al, 2009), swine wastewater (Li et al, 2010) and sugar-processed wastewater (Narihiro et al, 2009b); BT degradation may support brewery wastewater (Werner et al, 2011) and municipal sewage sludge treatment (Riviere et al, 2009); and BZ degradation may facilitate treatment of wastewater containing terephthalate, phenol and other petrochemicals (Wu et al, 2001a,b;Chen et al, 2009;Perkins et al, 2011). Syntrophorhabdus was only found in AD-treating terephthalate and phenol (Chen et al, 2008; (Fig.…”

The Microbiology of Olive Mill Wastes

“…Syntrophus spp., which were in syntrophic relationship with methanogenic Archaea , were detected, while sulphate-reducing bacteria were identified as the result of the high sulphate concentration in the OMW digested. Next to Clostridia , which are predominant during acidogenesis, Syntrophus and Chloroflexi -like bacteria appear to be also common inhabitants of phenolic wastewaters [83]. In fact, fermentative Clostridia convert phenolic derivatives to benzoate, which is subsequently transformed by Syntrophus -like strains to acetate and H 2 /CO 2 [84].…”