Researchers at Kobe University have discovered the mechanism by which members of the Cucurbitaceae family, including pumpkins, squash, gourds, melons and cucumbers, accumulate harmful pollutants in the edible parts of the plant. The study was published in the journal Plant Physiology and Biochemistry (PPB).
Cucumbers can absorb persistent contaminants from the soil, which then concentrate in the fruit and can pose a health risk. However, most other cultivated plants do not.
"These pollutants are poorly broken down and can accumulate in the human body. We wanted to understand why the Cucurbitaceae family behaved in such an unusual way," said Kobe University agricultural biologist Professor Hideyuki Inui.
Inui's team previously identified a special class of proteins that bind pollutants and help them move through the plant. The scientists also found that the shape of these proteins and their ability to bind toxic substances affects the amount of pollutants that reach aboveground parts. However, the issue remained unclear. why even within a single species do some species accumulate more toxins than others?
The new experiments showed that varieties prone to the accumulation of pollutants contain more of these proteins in their juice, while in others they remain inside the cells. The main difference is a small difference in the amino acid sequence, which serves as a kind of "tag" and determines whether the protein will be secreted into the juice.
"Only the secreted proteins are able to move through the plant and reach the fruit. This is the factor that differentiates varieties with high levels of contamination from those resistant to it,” Inui explained.
Understanding this mechanism paves the way for safer vegetable cultivation.
"If we can control the behavior of contaminant-transporting proteins by changing their ability to bind toxins or prevent their release into the sap, we can grow plants that do not accumulate harmful substances in their fruits," the researcher noted.
Moreover, the scientist sees in this discovery the potential of phytoremediation, the treatment of polluted soils using plants.
“We can use this knowledge to create crops that efficiently absorb pollutants from the soil. This will allow us to turn common plants into bioengineered systems for environmental cleanup," Inui added.
Translation by Euromedia24.com
