Bakeries and wineries can't survive without yeast, but they don't need green algae. Wastewater treatment plants, on the other hand, could benefit from the cooperation of these microorganisms. Researchers at Osaka Metropolitan University have discovered that these simple organisms form the best combination when it comes to increasing the efficiency of wastewater treatment.
The activated sludge process for wastewater treatment requires electricity to ensure the flow of oxygen that feeds the bacteria and other organisms that process the water. The addition of microalgae for photosynthesis, which produces oxygen, improves energy efficiency, but low carbon dioxide levels inhibit their growth. This is where the yeast Saccharomyces cerevisiae comes in, producing carbon dioxide.
Led by Associate Professor Ryosuke Yamada of the Graduate School of Engineering, the group investigated which combination of these types of microorganisms offered the highest efficiency in wastewater treatment. The group found that the combination of the green algae Chlamydomonas reinhardtii and yeast had the best efficiency. This was reported to the researchers for the first time. Remarkably, the combination improved the green algae's ability to absorb ammonium and phosphate ions.
"The green algae and yeast are very harmless to humans, especially considering that treated wastewater is discharged into the environment," explained Professor Yamada. "These microorganisms can also accumulate beneficial compounds such as polysaccharides, fats, and oils in their cells and be used as microbial fertilizers. Therefore, it can be assumed that beneficial compounds are simultaneously produced during wastewater treatment."
https://link.springer.com/article/10.1007/s00253-024-13309-w
