Fungi that absorbs uranium
fungi gel well with uranium, says a recent study from the uk. Depleted uranium, a radioactive by-product of uranium enrichment process in nuclear reactors, is used widely in ammunition. Being radioactive, there are concerns about its effect on the health of people exposed to it. The study says depleted uranium contamination can be cleaned up by using a certain class of fungi. The fungi absorb the uranium.
Depleted uranium in the metallic form is unstable and easily reacts with moisture to form uranium oxides. The process leads to formation of yellow and black products of oxidization when fungi are present. This corrosion results in loss of weight of the depleted uranium pieces, says the study published in the May 6 issue of Current Biology.
Presence of uranium within the fungi could be seen by the yellow tinge of the fungi indicating it accumulated the uranium. The fungi also had crystals of uranyl phosphate on their surface. They belong to a group that produces penicilin and also yeast used in brewing.
The researchers claim this is the first study that explains the mechanism of depleted uranium breakdown by fungi. They also suggest that this feature of fungi could be used to clean up places contaminated by depleted uranium.
"It seems the uranium is just deposited and not put to any use by the fungi. While other organisms may further break uranium down, it is likely to persist even after the fungi die,' says Geoffrey Gadd of University of Manchester and one of the authors. "The problem could be taken care of if uranium could be extracted from the fungi and re-used,' says I S Thakur, professor, School of Environmental Sciences, Jawaharlal Nehru University, Delhi.