Is the floating freshwater fern commonly called Carolina azolla the potential answer to global food insecurity or a possible threat to humanity? Following a study published earlier this year by Penn State researchers on the plant’s nutrition and digestibility, the team learned of concerns about the plant’s possible toxin content. Researchers joined an international effort to test Azolla and found that it does not contain cyanotoxins, potent toxins produced by a type of cyanobacteria or blue-green algae associated with the plant.
The team published their findings in a new study in Floors.
“That finding suggests that azolla is food safe and has the potential to safely feed millions of people due to its rapid growth while floating freely in shallow fresh water without the need for nitrogen fertilizers,” said Daniel Winstead, a technologist. researcher at Penn State’s College. of Agricultural Sciences and lead author of the previous study. He works in the laboratories of Michael Jacobson, professor of ecosystem science and management, and Francesco Di Gioia, assistant professor of vegetable crop science. “Azolla is an amazing plant that can double its biomass in two days and capture nitrogen from the air.”
After publication of the original study, Winstead said it came to her attention that cyanobacteria living inside azolla could produce powerful cyanotoxins that deter animals from eating the plant. Cyanotoxins have been linked to neurodegenerative disorders such as amyotrophic lateral sclerosis (ALS) and Parkinson’s disease, liver and kidney failure, muscle paralysis, and other serious health problems. Despite the threat of toxins and the use and study of azolla, he explained that they learned that no scientist had definitively proven the presence of these toxins in azolla.
“I felt a responsibility to help answer this question because we had just published about the nutritional quality of azolla,” Winstead said. “I did not want to promote the consumption of a potentially harmful plant. While I was preparing an experimental design, the Azolla Foundation contacted me about that organization’s interest in our research. I approached them and asked if they knew anyone who was researching cyanotoxin toxicity of azolla”.
Several weeks later, she received an email saying that a group of researchers was investigating cyanobacteria-cyanotoxins in the azolla question, and they invited Winstead to be part of the study.
“Together we analyzed the results and concluded that azolla, and more specifically a cyanobacterium that lives in cavities in azolla leaves, does not produce any of the main cyanotoxins,” he said, explaining that the azolla cyanobacterium is Nostoc azollae, an endosymbiont or organism that lives within or on the surface of another organism in a mutually beneficial relationship. “More importantly, the known genes necessary to produce these toxins are not even present in the Nostoc azollae genome.”
According to Winstead, this discovery adds to a growing body of evidence that azolla could be widely used to solve several global challenges.
“It could help feed many people in need around the world, in addition to becoming a new source of biofertilizers and biodiesel,” he said.
Also part of the research team were Jonatha Bujak and Alexandra Bujak, from the Azolla Foundation, Blackpool, United Kingdom; Ana Pereira, Joana Azevedo and Vitor Vasconcelos, University of Porto, Portugal; Victor Leshyk, Azolla Biodesign, Sedona, Arizona; Minh Pham Gia, independent researcher, Hanoi, Vietnam; and Timo Stadtlander, Organic Agriculture Research Institute, Frick, Switzerland.
Open Philanthropy, Penn State: The Emergency Food Resilience Research Project financially supported this research.