Characterization of the microbial community in the anaerobic/oxic/anoxic process combined with sludge ozonation and phosphorus adsorption

Abstract

In this study, the microbial community in the anaerobic/oxic/anoxic (A/O/A) process combined with sludge ozonation and phosphorus recovery was characterized by using phosphorus uptake rate (PUR) analysis and PCR-cloning analysis. Despite effective phosphorus removal, PUR analysis indicated a lower activity of both polyphosphate-accumulating organisms (PAOs) and denitrifying PAOs (DNPAOs) than in other systems utilizing DNPAOs. This result suggested that endogenous denitrifying bacteria actively contributed to denitrification. The PCR-cloning analysis revealed that Bacteroidetes was most prominent in the process, followed by Betaproteobacteria and Alphaproteobacteria. For Bacteroidetes, most of the sequences obtained in this study were not closely related to isolates. On the other hand, for the Alphaproteobacteria, the genera Amaricoccus, Aminobacter, Hyphomicrobium, and Paracoccus, which have the ability both to accumulate poly-β-hydroxybutyrate (PHB) and to reduce nitrate to nitrite, were detected. For the Betaproteobacteria, which are major denitrifying bacteria in wastewater treatment systems, the genera Dechloromonas and Zoogloea, were identified. Organisms belonging to the family Comamonadaceae, some of which have been reported as being primary poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV)-degrading denitrifying bacteria, also existed in the system. Major PAOs/DNPAOs, Rhodocyclus-related PAOs and Actinobacterial PAOs, were not detected, suggesting that unknown PAOs/DNPAOs could have played an important role for phosphorus removal.

Linking bacterial population dynamics and nutrient removal in the granular sludge biofilm ecosystem engineered for wastewater treatment

“…Aminobacter sp. inside Rhizobiales can accumulate poly-b-hydroxyalcanoates and reduce nitrate to nitrite (Urakami et al, 1992;Kondo et al, 2009). According to denitrifying and exopolysaccharide-producing physiological properties, these populations might therefore play an important role in the microbiomes of AGS biofilms.…”

A Comparative Study of the Bacterial Community in Denitrifying and Traditional Enhanced Biological Phosphorus Removal Processes

“…Candidatus “Accumulibacter” may have also adapted to different ecological environments and exhibits various physiological properties similar to DPAO ( 5 , 11 , 12 , 15 ). In addition to the clades of Candidatus “Accumulibacter”, Dechloromonas- related bacteria had been detected in several EBPR processes operated under partially anoxic conditions ( 15 , 17 , 19 ). However, whether they function as PAO remains controversial.…”

Determination of Microbial Community in a Pilot Scale Two-Stage Step-Feed Biological Nutrient Removal Process

“…of Beta-proteobacteria was identified in the 4 th band. It has been broadly reported in several studies that such bacteria plays an important role in the denitrification of nitrogenous species in municipal wastewater (Ding et al, 2011;Kondo et al, 2009). The 5 th band was identified as uncultured Candidatus Accumulibacter sp.…”