Carolinian azolla could save humanity in the event of a catastrophe. This unused plant can double its biomass in two days, capture nitrogen from the air and feed birds and livestock, so it has great potential for human consumption.
Native to the eastern US, azolla caroliniana could alleviate food insecurity in the near future, according to findings recently published in Food Science
The study, led by Daniel Winstead, a research assistant at Pennsylvania State University, is part of a larger interdisciplinary research project called ‘Food Resilience to Global Catastrophic Events’ conducted in the College of Agricultural Sciences.
“Other species of azolla have been used around the world for several thousand years as livestock feed and as ‘green manure’ to fertilize crops due to the plant’s ability to fix nitrogen,” Jacobson said in a statement. “It was thought that the use of azolla for human consumption was limited by its high total polyphenol content, which interferes with its digestibility. But this research shows that the phenolic content of the Carolina strain is much lower and cooking the plant decreases it even further “.
Polyphenols, which are naturally abundant compounds found in plants, at lower concentrations are beneficial to human health due to their antioxidant activity. But high concentrations of polyphenols can limit the body’s absorption of nutrients and act as anti-nutritional factors, Jacobson explained. Gallic acid is a stable phenol and has become a standard measure for determining phenol content in foods.
In the study, azolla caroliniana, which has been described as having a crunchy texture and neutral flavor, was grown in a greenhouse located on the Penn State University Park campus. The researchers determined that it has a total phenolic content of approximately 4.26 grams, gallic acid equivalents per kilogram of dry weight.
This measurement compares to fruits, Winstead noted, which are generally between 1.4 and 6.2; beans between 1.2 and 6.6; and walnuts, between 0.5 and 19. By comparison, he added, other azolla species growing in Asia and Africa weigh between 20 and 69 grams, gallic acid equivalents per kilogram of dry weight, too high for humans to digest. comfortably.
The researchers tested three cooking methods (boiling, pressure cooking, and natural fermentation) that multiple studies have shown can decrease polyphenol content in foods, with the goal of reducing anti-nutritional factors that potentially restrict azolla consumption. by both humans and livestock. Tests showed that the total phenol content was reduced by 88%, 92% and 62% with boiling, pressure cooking and natural fermentation, respectively, compared to the raw plant.
This variety of azolla, sometimes called mosquito fern, fairy moss and water fern, has excellent potential for use as a fast-growing, short-season crop that requires minimal inputs, maintenance and processing, Winstead said, adding that the plant could be used to increase food supply.
“Our study highlights the nutritional value and moderate protein content of this azolla and demonstrates that cooking methods easily and significantly reduce the total phenolic content,” Jacobson said. The moderate protein and high mineral yields of azolla make this species desirable for cultivation.
“The easy and fast-growing nature of azolla cultivation makes it an ideal resource during disasters and catastrophes, as well as for regular use on small farms and low-income areas,” the researchers concluded. It is a multipurpose wild edible plant that has great potential for economic, agricultural, nutritional and resilience benefits, but needs further development.
“Whether for a ‘quick fix’ in disaster scenarios or a long-term resilience plan, azolla caroliniana has the potential to provide large amounts of protein and calories for people and livestock,” the experts comment. They also point out that the plant has been considered for inclusion in the United States space program. If azolla cultivation and preparation systems can be made more efficient, growing it indoors or outdoors after natural disasters could provide supplemental production of climate-resilient nutrients.
