Sulfated yeast rises to the challenge facing rare earth metals

Osaka Metropolitan University researchers develop innovative S-yeast solution, significantly enhancing metal adsorption and recycling efficiency.

From Osaka Metropolitan University 22/10/25 (first released 17/10/25)

By introducing a sulfate group, rare metal adsorbing S-yeast was created. Credit: Osaka Metropolitan University

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.