Stratification of Extracellular Polymeric Substances (EPS) for Aggregated Anammox Microorganisms

Abstract

Sludge aggregation and biofilm formation are the most effective approaches to solve the washout of anammox microorganisms. In this study, the structure and composition of EPS (extracellular polymeric substances) were investigated to elucidate the factors for the anammox aggregation property. Anammox sludge taken from 18 lab-scale and pilot-scale reactors treating different types of wastewater was analyzed using EEM-PARAFAC (excitation-emission matrix and parallel factor analysis), FTIR (Fourier transform infrared spectroscopy) and real-time PCR combined with multivariate statistical analysis. The results showed that slime and TB-EPS (tightly bound EPS) were closely related with water quality and sludge morphology, and could be used as the indicators for anammox microbial survival ability and microbial aggregate morphology. Furthermore, slime secreted from anammox bacterial cells may be exhibited higher viscosity to the sludge surface and easily formed the gel network to aggregate. Large amounts of hydrophobic groups of protein in TB-EPS promoted the microbial aggregation. The mechanisms of anammox aggregation explored in this study enhanced the understanding of anammox stability in wastewater treatment processes.

Characteristics of Nitrogen Removal and Extracellular Polymeric Substances of a Novel Salt-Tolerant Denitrifying Bacterium, Pseudomonas sp. DN-23

“…Among the FT-IR results, the C = O stretching vibration was related to β-sheets in secondary protein structures, which favored bio-flocculation (Badireddy et al, 2010). Additionally, the bands of C-H stretching, C = O symmetric stretching, and C-C stretching in EPS represent hydrophobic functional groups, which may contribute to the auto-aggregation of cells (Jia et al, 2017). Furthermore, the existence of Tyrosine in EPS also provided more evidence for maintaining the stability of granular structures (Zhu et al, 2012).…”

Enhanced biological removal of intermittent VOCs and deciphering the roles of sodium alginate and polyvinyl alcohol in biofilm formation

“…Biofilm formation capacity was evaluated by absorbance at 600 nm. EPS were extracted according to the method of Jia (2017) with some modification [21]. In brief, four patches of packing material were washed with PBS.…”

Carbon quantum dots derived from the extracellular polymeric substance of anaerobic ammonium oxidation granular sludge for detection of trace Mn(vii) and Cr(vi)

“…The method for extraction of EPS from the anammox granular sludge was modied according to the study by Jia et al 15 In brief, 200 mL of anammox granular sludge was collected and cleansed with deionized water. Next, the anammox biomasses were placed to a blender with addition of deionized water to obtain a suspension of 500 mL before they were being crushed for 5 min.…”