Research News

Oct 17, 2025

  • Engineering

Sulfated yeast rises to the challenge facing rare earth metals

Modified yeast developed to efficiently adsorb targeted elements from solutions

Sulfated yeast


By introducing a sulfate group, rare metal adsorbing S-yeast was created.


Credit: Osaka Metropolitan University

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Ever wonder what happens to those old, broken electronics after tossing them? How about how new ones are being produced despite dwindling resources? The seemingly endless supply of gadgets hides an increasingly critical problem, limited raw resources.

Electronics, optical fibers, and superconducting materials heavily rely on rare earth metals, but such limited resources lack innovative recycling solutions. Various methods do exist for metal recovery, but technology with low environmental impact and costs is rising in demand.

Fortunately, an answer may have been found in the common kitchen ingredient, baker’s yeast. A research group led by Professor Masayuki Azuma and Associate Professor Yoshihiro Ojima at Osaka Metropolitan University’s Graduate School of Engineering successfully achieved selective recovery of metals with S-yeast, a sulfated yeast. When testing the removal of copper (Cu) from a solution, S-yeast’s metal adsorption capacity was found to absorb approximately 2.3 times more than the phosphate-modified baker's yeast (P-yeast) previously created in their past studies.

Furthermore, S-yeast can desorb Cu using hydrochloric acid, then adsorb it again; effectively providing a possible sustainable and cost-effective solution to metal recovery. Additionally, it was found that S-yeast adsorbs more zinc, cadmium, lead, and rare earth elements than P-yeast.

“We hope these research findings lead to applications in efficient and environmentally-friendly rare earth recovery technology. Moving forward, we plan to advance toward practical implementation by scaling up material production and conducting evaluations using actual waste liquids,” stated Professor Azuma.

The study was published in Environmental Research.

Paper information

Journal: Environmental Research
Title: Excellent adsorption performance of sulfated yeast for heavy metal ions: High capacity and selectivity for rare earth elements
DOI: 10.1016/j.envres.2025.122743
Authors: Kokoro Yamada, Moena Amano, Yoshihiro Ojima, Hideki Azuma, Koichi Igarashi, Masayuki Azuma
Published: 1 September 2025
URL: https://doi.org/10.1016/j.envres.2025.122743

Contact

Masayuki Azuma
Graduate School of Engineering
Email: azuma[at]omu.ac.jp

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