Abstract:

The yeast (Saccaromyces cerevisiae) absorption of uranium was studied by using Scanning Electron Microscope (SEM),
Fourier Transform  Infrared Spectrometry  (FTIR) and Energy Dispersive X-ray Spectroscopy  (EDXS). The SEM  results showed 
that yeast cell surface was covered with uranium crystal and the quantity of crystal increased with concentration of uranium and
the interaction time. The surface morphology of yeast changed greatly with incubation time. EDXS analysis showed that the crystal
of uranium was formed via adsorption on the surface of S. cerevisiae. FTIR results revealed that the peak attributed to υs(O-H) of
yeast cell surface shifted about 29 cm-1 to lower wavenumbers. Both peaks of υ s(C-OH) and υs(-PO2-) shifted about 21 cm-1
 to lower wavenumbers, and the band attributed  toυ C=O of the carboxyl group almost disappeared. The formed crystal  is considered
to be autunite according to the FTIR characteristic absorption band. These results indicated that the UO22+ can be stabilized via
adsorption by S. cerevisiae

Key words: Yeast (Saccaromyces cerevisiae), uranium, absorption, surface-interaction