Scientists deem tiny fern azolla a promising solution for global food insecurity

A new study has confirmed that Carolina azolla, a fast-growing floating fern, is free of harmful cyanotoxins and also holds potential as a sustainable food source to tackle global food insecurity. 

With the ability to rapidly double its biomass and fix nitrogen from the air, researchers believe the freshwater plant, also known as mosquito ferns, could play a crucial role in alleviating global food insecurity.

Research technologist at Penn State’s College of Agricultural Sciences, Daniel Winstead, tells Nutrition Insight about azolla’s unique nutritional profile, rapid growth and low-resource cultivation, making it a viable option for feeding millions in need.

How can the nutrition industry scale and use azolla to combat food insecurity?
Winstead: The wonderful thing about azolla is that it has so much potential across a wide range of uses. Breeders could produce crop varieties of azolla that create heightened protein content, different tastes, increased growth rate, increased vitamin content, greater fat content and more.

It is essentially a blank slate waiting to be formed into what we need it to be. A major area of need is to create good-tasting azolla strains that can garner the support of researchers and farmers worldwide.

How does azolla’s nutritional profile compare to other sustainable food sources?
Winstead: Azolla is unique in its nutritional profile because it has very high mineral content and a complete protein profile. This means that azolla has all of the amino acids present to create proteins in the human body, which is uncommon among plant proteins.

Azolla is food-safe and has the potential to feed millions of people due to its rapid growth while free-floating on shallow freshwater without the need for nitrogen fertilizers (Image credit: Penn State).IIt is particularly high in tryptophan and also has a high polyphenol content, which, if managed well, is a great source of antioxidants.

What is the main takeaway of your research?
Winstead: The main takeaway from this research article is that azolla does not contain cyanotoxins and is further evidence that azolla is a safe food or animal feed source.

We used three techniques to rule out cyanotoxin presence in azolla. We used DNA replication techniques to determine if the cyanobacteria within seven species of azolla contained the genes required to produce known cyanotoxins. All of these tests showed that azolla’s symbiont, Nostoc azollae, does not have the genes to produce cyanotoxins. 

We also used the known genome of Nostoc azollae to search for genes required to produce cyanotoxins. These genes were not present either. 

Finally, we used a technique called mass-spectrometry to detect β-Methylamino-L-alanine (BMAA) molecules in samples of azolla, a neurotoxin produced by cyanobacteria. All of these tests showed no presence of BMAA.

How can azolla benefit countries facing food insecurity and its agricultural applications?
Winstead: Azolla’s ability to not only double its size in two days but also fix nitrogen from the air gives it the unique ability to quickly produce fresh produce even with limited space and fertilizer.

Azolla’s symbiont, Nostoc azollae, is the actual organism that is doing the nitrogen-fixing. This not only means that you can grow azolla with limited nitrogen fertilizers, but it can also produce nitrogen fertilizer to be used as “green manure.”

In other developments targeting food insecurity, professors from the University of Arizona, US, are developing a cost-effective, spirulina-based nutrition solution in bioreactors to combat global food insecurity and malnutrition, especially in climate-affected regions.

Separate research warns that food insecurity in children’s early lives or among pregnant mothers increases the risk of obesity or severe obesity in childhood and adolescence by 50%.