Abstract
Bioleaching is a prominent method among eco-friendly techniques. The efficiency of bioleaching is reduced by the presence of brackish water. Moreover, it has been reported that the most successful bioleaching systems are those that include both autotrophic and heterotrophic microorganismes. This research focuses on enhancing uranium bioleaching in brackish waters using the halotolerant bacterium Acidithiobacillus ferrooxidans strain THA4 and the fungus Rhodotorula toruloides strain IR-1395. The experimental data were modeled by the Response Surface Methodology (RSM) approach. The suggested model for uranium extraction in a brackish environment using microorganisms demonstrated an alignment with the experimental data, with a correlation coefficient of R2 = 0.94. The results showed that the amount of uranium bioleaching by the consortium increased by 24.22%, compared to the bacterium alone under the optimal conditions suggested by the software. The study employed SEM–EDS to investigate the morphological changes in ore samples exposed to the microorganisms. The findings offer insights into the relationship dynamics between acidophilic bacteria and heterotrophic yeasts in uranium bioleaching of brackish waters. Finally, this study has improved biohydrometallurgical methods for uranium extraction from low-grade ores, especially in saline and low-resources conditions.
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Data availability
All data generated or analyzed during this study are included in this article. The 16S rDNA sequence of Acidithiobacillus ferrooxidans strain THA4 had been deposited in the National Center for Biotechnology Information (NCBI) GenBank with the accession number PV981793 (https://www.ncbi.nlm.nih.gov/nuccore/PV981793). The 18S rDNA sequence and large subunit rDNA sequence of Rhodotorula toruloides strain IR-1395 had been deposited in the National Center for Biotechnology Information (NCBI) GenBank with the accession number KX452402.1 and MN752210.1, respectively (https://www.ncbi.nlm.nih.gov/nuccore/KX452402 and https://www.ncbi.nlm.nih.gov/nuccore/MN752210).
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Acknowledgements
This manuscript was a part of the PhD. thesis by M. Shoja, under the supervision of Dr. P. Mohammadi and Dr. P. Tajer-Mohammad-Ghazvini; and advi¬sory of H. Zare-Tavakoli. The authors would like to thank Alzahra University and also Nuclear Science and Technology Research Institute, Tehran, Iran for their support through this study.
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The manuscript was a part of the PhD. thesis by M. S. All the authors contributed to the conception and design of the study. M. S.: conducting experiments, writing (original draft preparation). Dr. P.M.: writing (review and editing), supervision. Dr. P. T-M-G.: writing (review and editing), supervision, software. Dr. H. Z-T.: adviser. All authors read and approved the final manuscript.
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Shoja, M., Mohammadi, P., Tajer-Mohammad-Ghazvini, P. et al. Improved uranium bioleaching in brackish environments via microbial consortium using RSM based modelling and optimization. Sci Rep (2026). https://doi.org/10.1038/s41598-026-39700-3
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DOI: https://doi.org/10.1038/s41598-026-39700-3
