Single-celled Euglena gracilis is multi-talented. A member of the protist kingdom, it can both convert light energy into sugar (like a plant) and consume metabolize sugars (like an animal). These qualities make it an interesting experimental organism that has led Trent researchers to discover that Euglena can do much more. 

"We're working on a few connected projects that aim to use Euglena biology in real-world applications," said Dr. Neil Emery, professor of Biology at Trent and lead researcher of the Emery Lab. "The more we work with it, the more capable it appears to be." 

Researchers in the Emery Lab have found Euglena can detoxify cassava waste and add protein to staple foods. They're also using CRISPR gene-editing technology to reveal surprising insights into the organism's biology that could lead to entirely new applications.

Breaking down cassava waste into wanted resources

In research recently published in the Journal of Visualized Experiments (JoVE), Professor Emery's team developed an open-access method for using Euglena to process waste generated by cassava production. 

Cassava is a staple food for hundreds of millions of people across Africa, South America, and Asia, but processing the crop leaves behind large quantities of peel waste containing naturally occurring cyanide compounds that can create environmental challenges. 

Working with Nigerian cassava processor Psaltry International, the Trent team demonstrated how Euglena can be cultured directly on cassava peel waste to break down the toxic cyanide while producing nutrient-rich biomass that can be harvested separately. 

"The process was designed to be accessible so it could be adopted beyond industrial facilities," said Zsofia Hatvani, a Trent Forensic Biology alum and research technician in the Emery Lab who demonstrated the methodology for JoVE, alongside Adrian Guaman Vargas, a Conservation Biology co-op student supporting research in Prof. Emery's lab. "The goal was to design something that families and small processors could do." 

Publishing the research in JoVE also makes it possible for wide adoption.  

"We wanted to make the research open access so people can use the technology, make it free of charge, and make it easy to replicate," said Prof. Emery. 

Transforming Euglena into something edible

The Euglena that grows on the cassava peel waste is what becomes a protein dietary supplement. Cassava flour and garri naturally contain very little protein, so the research team investigated the possibility of blending dried Euglena biomass grown during the detoxification process back into those staple foods. 

"Commercial cassava flour and garri samples tested by the researchers contained between 0.63 and 1.25 per cent protein," said Prof. Emery. "We mixed Euglena flour with both cassava flour and garri and obtained much elevated protein content, between five and 22 percent, comparable to many meats, cheeses and tuna. We had taste testing done as well to understand at what levels Euglena could be added without affecting texture and flavour too much." 

The findings point to a circular approach that addresses two challenges simultaneously: reducing waste from cassava processing while producing a more nutritious food product. 

Explore new applications of the algae

Alongside the new applied research, other researchers in the Emery lab are experimenting with the protist's potential. 

Research scientist Dr. Zhiyong Zhang has created several gene-edited strains of Euglena using CRISPR technology, selectively turning off individual genes to better understand how they influence the organism's growth, metabolism, nutrition, and behaviour. 

"We're comparing the genetically edited Euglena cell lines with the original wild type to better understand gene functions and how changes in key metabolic pathways affect the organism's behaviour," says Dr. Zhang. "It's fundamental biology research that could lead to new applications and ideas." 

Among the most intriguing discoveries so far has been what happens when genes involved in producing cytokinins—a class of plant hormones Prof. Emery has studied for more than 30 years—are switched off. 

"We don't really know much about what cytokinins do in algae or protists like Euglena, and knocking them out has caused quite a change in the phenotypes," said Prof. Emery. 

Also supporting the work are Alicia Parker, a biotechnology student at Fleming College, and Olivia Symons, a Grade 11 science research student completing a seven-week internship in the lab. Olivia, who is also the granddaughter of Trent University's founding president Tom Symons, has been helping document the appearance and behaviour of the newly developed mutant strains alongside Dr. Zhang and Parker. 

The research team's simultaneous streams of discovery are advancing innovation in life sciences. Through both fundamental and applied investigations, they are illuminating the potential of living organisms like Euglena and offering new avenues and solutions for questions related to global food production, health and environmental sustainability.  

Learn more about Biology and Conservation Biology at Trent University.