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bioRxiv · 10.1101/2024.07.02.601720

Establishing a co-culture aggregate of N-cycle bacteria to elucidate flocculation in biological wastewater treatment

Parret, L.·Simoens, K.·Horemans, B.·De Vrieze, J.·Smets, I.
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Abstract

Biological flocculation is a complex phenomenon that is often treated as a black box. As a result, flocculation problems are usually remediated without knowledge of the exact causes. We show that it is feasible to exploit a model (N-cycle) consortium with reduced complexity to fundamentally study bioflocculation. Strong nitrifier microcolonies were formed during oxic/anoxic cycles in sequencing batch reactors, using alginate entrapment as a cell retention system. After release of these aggregates into suspension, macroclusters with flocs of the denitrifier were observed. These results suggest that a living model of a full-scale activated sludge floc can be built through the use of this bottom-up approach. By eliminating shifts in the microbial community, the applied experimental conditions have a more direct effect on the observations.

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Parret, L., Simoens, K., Horemans, B., De Vrieze, J., Smets, I.. 2024-07-02. Establishing a co-culture aggregate of N-cycle bacteria to elucidate flocculation in biological wastewater treatment. https://doi.org/10.1101/2024.07.02.601720

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