Synechococcus PCC 7002 to produce a carbohydrate-rich biomass treating urban wastewater

Abstract

In this paper, Synechococcus PCC 7002 was cultivated in urban wastewater and its depurative capacity was evaluated to remove chemical oxygen demand (COD), nitrogen (N) and phosphorus (P) content producing a carbohydrate-rich biomass. Preliminary studies demonstrated 28 °C and no injection of concentrated CO₂ as suitable conditions to perform the biological treatment and to obtain a depurated water with characteristics below the law limit for COD, N and P. Using concentrated synthetic wastewater to verify the extended capacity to treat several range of wastewaters, Synechococcus proportionally decreased the capacity of pollutants removal showing that probable an environmental/nutritional factor was not completely simulated by the synthetic wastewater what harm Synechococcus performance and was determined as lacking micronutrients. Real wastewater experiments validated the potentiality of this strain to wastewater bioremediation also reaching values of COD, N and P, below the law limit (> 80% of removal rate) and a biomass with up to 60% of carbohydrate content was produced.

Keywords:

• cyanobacteria
• nitrogen
• phosphorous
• micronutrient
• biological treatment

Acknowledgements

The authors thank CNPq – Brazil (National Research Council of Brazil) - Process numbers 249182/2013-0, 407274/2018-9 and 313195/2019-6 for resources and fellowship.

Disclosure statement

No potential conflict of interest was reported by the author(s).