Clarification of cyanotoxins in El Guajaro Reservoir, Colombia using a microalgae‐based consortium MPMC

Abstract

BACKGROUND Cyanobacteria blooms occur in freshwater and saline ecosystems under certain environmental conditions, such as eutrophication, that are often accompanied by the production of cyanotoxins; Those biological toxins are a risk to the health of animals and humans. The eutrophication of water bodies is becoming more frequent due to organic pollution pressure from swage discharge, so outcrops are frequent and difficult to manage by the communities affected by these phenomena. Most of the control mechanisms for these events are carried out through nutrient input constraints, sonication, and (more recently) biological control. RESULTS In this work, a cyanobacterial bloom in a reservoir in a tropical zone of northern Colombia was characterized. The microbiological dominance of Microcystis sp. and the presence of microcystin in the water were documented. A bioaugmentation process was then tested with a microbial consortium containing a predominance of microalgae (MCPM); after this, the dominance of cyanobacteria was broken and the richness and density of the phytoplankton were recovered. The decrease in cyanobacterial density was documented 15 days after the MCPM bioaugmentation began. A significant removal (34% to 53%) of Microcystis sp, was observed between days 1 and 16; from day 16 to day 58, removal of Microcysis sp reached 92% to 100%. The bioaugmentation took a total of 58 days. CONCLUSION This work raises the possibility of using the competitive inhibition capacity of nonharmful microalgae on cyanobacteria as an ecological tool to counteract blooms and mitigate the risk of cyanotoxins for animals and humans. © 2021 Society of Chemical Industry (SCI).

Changes in Extracellular Microcystins (MCs) Accompanying Algae/Cyanobacteria Removal during Three Representative Algae/Cyanobacteria Inactivation Processes and an MC Diffusion Model in Still Water

“…The widespread eutrophication of water bodies has significantly increased the frequency of algae/cyanobacteria blooms in China. Decomposing algae/cyanobacteria blooms consume a massive amount of dissolved oxygen in water [1,2], resulting in deteriorated water quality [3]. In addition, Microcystis aeruginosa is one of the cyanobacteria most prone to blooms [4].…”

Special Issue: biotechnology advances in Latin America

“…Likewise, Banda et al 11 performed physiological and kinetic evaluations of a denitrifying sludge using ampicillin as the only electron source, showing that denitrification processes allow the simultaneous oxidation of recalcitrant compounds and nitrate reduction during wastewater treatment. Gutiérrez et al 12 reported that bioaugmentation with microalgae can be used to avoid the predominance of cyanobacteria in water bodies, reducing the risk of cyanotoxins for animals and humans.…”