Coupling extracellular glycan composition with metagenomic data in papermill and brewery anaerobic granular sludges

Glycans are crucial for the structure and function of anaerobic granular sludge in wastewater treatment. Yet, there is limited knowledge regarding the microorganisms and biosynthesis pathways responsible for glycan production. In this study, we analysed samples from anaerobic granular sludges treating papermill and brewery wastewater,...

Enhancement of fire resistance and mechanical performance of polypropylene composites containing cellulose fibres and extracellular biopolymers from wastewater sludge

In the present research, a bio-based flame retardant (FR) was prepared using a biopolymer derived from wastewater sludge to improve the fire performance of polypropylene (PP). Extracellular polymeric substances (EPS), which were extracted from wastewater aerobic granular sludge, were absorbed into cellulose-based fibres, such as flax and...

Turnover of the extracellular polymeric matrix of granules performing biological phosphate removal

Polyphosphate accumulating organisms (PAOs) are responsible for enhanced biological phosphate removal (EBPR) from wastewater, where they grow embedded in a matrix of extracellular polymeric substances (EPS). EPSs comprise a mixture of biopolymers like polysaccharides or (glyco)proteins. Despite previous studies, little is known about the...

Insight on how biopolymers recovered from aerobic granular wastewater sludge can reduce the flammability of synthetic polymers

Eco-friendly flame retardants are greatly required to meet the expectations of low-toxicity, environmental compatibility and sustainability. Extracellular polymeric substances (EPS), the biopolymers recovered from excess granular wastewater sludge, have been successfully incorporated into poly(vinyl alcohol) (PVA) by a solution casting method...

Assessment of the impact of temperature on biofilm composition with a laboratory heat exchanger module

Temperature change over the length of heat exchangers might be an important factor affect-ing biofouling. This research aimed at assessing the impact of temperature on biofilm accumulation and composition with respect to bacterial community and extracellular polymeric substances. Two identical laboratory-scale plate heat exchanger modules...

Production of nonulosonic acids in the extracellular polymeric substances of “Candidatus Accumulibacter phosphatis”

Nonulosonic acids (NulOs) are a family of acidic carbohydrates with a nine-carbon backbone, which include different related structures, such as sialic acids. They have mainly been studied for their relevance in animal cells and pathogenic bacteria. Recently, sialic acids have been discovered as an important compound in the extracellular...

Formation and ripening of alginate-like exopolymer gel layers during and after membrane filtration

The properties of biofilm EPS are determined by the multiple interactions between its constituents and the surrounding environment. Because of the high complexity of biofilm EPS, its constituents' characterisation is still far from thorough, and identification of these interactions cannot be done yet. Therefore, we use gels of bacterial...

Aerobic granular sludge contains Hyaluronic acid-like and sulfated glycosaminoglycans-like polymers

Glycosaminoglycans (GAGs) are linear heteropolysaccharides containing a derivative of an amino sugar. The possibility of the presence of GAGs in aerobic granular sludge was studied by combining SDS-PAGE with Alcian Blue staining (at pH 2.5 and 1), FTIR, mammalian Hyaluronic acid and sulfated GAG analysis kits, enzymatic digestion and specific...

Glycosylated amyloid-like proteins in the structural extracellular polymers of aerobic granular sludge enriched with ammonium-oxidizing bacteria

A new type of structural extracellular polymers (EPS) was extracted from aerobic granular sludge dominated by ammonium-oxidizing bacteria. It was analyzed by Raman and FTIR spectroscopy to characterize specific amino acids and protein secondary structure, and by SDS-PAGE with different stains to identify different glycoconjugates. Its...

The acid soluble extracellular polymeric substance of aerobic granular sludge dominated by Defluviicoccus sp.

A new acid soluble extracellular polymeric substance (acid soluble EPS) was extracted from an acetate fed aerobic granular sludge reactor operated at 35 °C. Acid soluble EPS dominated granules exhibited a remarkable and distinctive tangled tubular morphology. These granules are dominated by Defluviicoccus Cluster II organisms. Acetic acid...