Study Finds Antioxidant Helps Some Plants Thrive in Metal-Enriched Soils

David Salt (right), a Purdue University professor of horticulture, and doctoral student John Freeman are investigating why certain plants thrive while others wither when exposed to large amounts of nickel in the soil. Their findings provide insight for the development of plants that can remove toxic metals from polluted sites or extract useful metals from soil, a process known as phytomining.

A Purdue study published in The Plant Cell found that plants that accumulate high levels of gluththione, an antioxidant, are much more tolerant to nickel. Plants require metals like nickel in minute quantities, but higher levels of such metals damages plant membranes. The research points to possibilities for developing plants that could be useful for cleaning polluted sites.

Antioxidants are, broadly speaking, compounds that protect cells from damage by exposure to certain reactive compounds.

Previous research has shown that most plants try to keep the levels of metals in their cells at a minimum, but plants called metal hyperaccumulators have the ability to build up unusually high levels of metals in their tissues without any ill effect. More than 400 plant species are now known that hyperaccumulate various trace metals. This research is some of the first data showing how plants protect themselves from metal contamination.

For more information, visit the Center for Phytoremediation Research and Development at https://www.purdue.edu/discoverypark/phytoremediation/index.html