9 June 2023

Microgreens biofortification is a tool to counter malnutrition


The biofortification process does work with smaller vegetables. According to Penn State University researchers,  soaking seeds in a zinc-based solution provides excellent results

by Matteo Cavallito


Biofortification of seeds made using zinc produces small, mature plants that can address malnutrition on a global scale, researchers at Penn State University claim. The investigation focused on so-called microgreens, or vegetables harvested shortly after planting that are particularly rich in nutrients, vitamins, minerals and antioxidants.

“Microgreens and sprouts are similar but they are not the same thing,” says a statement from the U.S based university. “A sprout is the first stage in a plant’s life cycle after the seed germinates. When the baby plant grows beyond its first shoot and root, it transitions to the microgreen stage. Microgreens are essentially the mature plant in miniature, with leaves, stems and roots.”


Biofortification is the cultivation process designed to increase the nutritional value of plants from seed. According to Francesco Di Gioia, professor of plant crop science and coordinator of the research group, simply soaking seeds in a zinc solution proves effective in producing particularly nutritious microgreens.

All of this is done without genetic engineering. That means this strategy can be easily replicated anywhere.

“We were thinking, how can we increase the content of zinc in microgreens, developing a very simple way that people could use at home in a ‘microgreens growing kit’ that could be delivered in an emergency situation,” explained Pradip Poudel, Ph.D., a doctoral student and co-author of the study. “And we know it will be important to include a fertilizer source for zinc so people will just have to soak the seeds before putting them in germination.”

The experiment

The experiment was carried out in 2021 in a greenhouse at the University of Pennsylvania. Researchers dipped seeds into the zinc solution and then measured the concentration of the element in microgreens of peas and sunflowers.

“Seed soaked in a 200 ppm ZnSO4 solution resulted in higher Zn accumulation in both peas (126.1%) and sunflower microgreens (229.8%),” the research states.

“However, an antagonistic effect on the accumulation of other micronutrients (Fe, Mn, and Cu) was seen only in pea microgreens.” The authors also observed that soaking the seeds in sulfate and zinc oxide solutions at higher concentrations had reduced phytic acid in the microgreens of both plants. Phytic acid is considered potentially harmful because it limits the uptake of important nutrients.

A resource against hidden hunger

Interest in biofortification has increased over the years in the face of the phenomenon of so-called “hidden hunger” or the shortage of micronutrients in the human diet. This lack may be the result of soil degradation, which in turn generates a loss of nutrients in the fruits of the earth.

According to World Health Organization estimates, quoted by the BBC, hidden hunger is said to affect mostly South Asia, South America and Sub-Saharan Africa.

The solution proposed by Penn State researchers could prove useful in addressing this problem. But also, the researchers argue, to provide a solution, at least in the short term, in the event of a global catastrophe. That is, in case a disruptive event were to threaten agricultural productivity.