Phototrophic microorganisms, which utilize light as an energy source, are pivotal in enhancing wastewater treatment and valorisation. Leveraging light to generate energy (ATP), these microorganisms can achieve high bioproduct yields. Research in Biogroup focuses on two main categories depending on the growth mode of phototrophic microorganisms: autotrophic and heterotrophic.

Autotrophic phototrophs

Research in this area mainly targets microalgae, which fix carbon dioxide to be used as a carbon source and remove nitrogen from wastewater while producing oxygen and nutrient-rich biomass. These autotrophic technologies are promising for efficiently eliminating nutrients from wastewater, preventing eutrophication, and reducing carbon dioxide levels.

At Biogroup, we emphasize the bioaugmentation of aerobic granular sludge (AGS) with microalgae, combining the activities of phototrophic and non-phototrophic bacteria. This synergy creates a system where aerobic bacteria in AGS benefit from the oxygen produced by microalgae. Together, these populations treat wastewater by removing organic carbon and nitrogen compounds in a compact, efficient system.

Heterotrophic phototrophs

Heterotrophic phototrophic organisms rely on organic carbon for growth. Due to their phototrophic nature, they utilize light to generate ATP, resulting in biomass yields of approximately 1 g COD/g COD consumed. Research on photoheterotrophic technologies focuses on developing photobioreactors enriched with mixed cultures of purple phototrophic bacteria (PPB). These bacteria are versatile, capable of using different substrates and operating under diverse conditions, making them ideal for urban biorefineries.

Our specific research at Biogroup targets the application of PPB to produce bioplastics (polyhydroxyalkanoates (PHA)) and fuels (biohydrogen) from volatile fatty acids (VFA) substrates. We also explore producing microbial proteins from agri-food industry wastes with moderate-to-high nitrogen content while removing pollutants.

Projects

· Unravelling the symbiosis of microalgae and bacteria in biofilms for implementation in wastewater resource recovery facilities (ALBA)
Spanish Government (Ayudas para incentivar la consolidación investigadora de la convocatoria 2022. (CNS2022-135142)

· Innovative decision-making tool for defining the most suitable manure management strategies to achieve a sustainable livestock farming system during the whole value chain (NUTRITIVE)
HORIZON-CL6-2023-ZEROPOLLUTION-02