Bioaugmentation of a structural extracellular polymeric substance (EPS) producer to improve activated sludge bioflocculation: lessons learned

Abstract Structural extracellular polymeric substances (EPS) contribute to the bioflocculation performance of activated sludge systems. This research investigates potential bioaugmentation a structural EPS producer, Azoarcus communis, as improvement or remediation approach. An antibiotic-resistant and fluorescent protein-producing mutant was constructed monitor survival, persistence, location augmented strain in membrane bioreactor. Preliminary batch tests against kaolin clay model system deflocculated revealed flocculation this strain. Morphological image analysis fluorescence microscopy suggest that most bacteria suspension were initially attached flocs with, however, only limited fraction getting incorporated within floc biomass. prevented assessing its impact on might be explained by metazoan protozoan grazing, together with competition indigenous organisms sub-optimal growth conditions reactor for engineered