Abstract
This study isolated and identified a new phosphate-solubilizing fungus strain, Talaromyces sp. MC-F2, based on morphological characteristics and phylogenetic analysis, from agricultural soil. Its capacity to solubilize tricalcium phosphate (TCP) was systematically evaluated in Pikovskaya (PVK), National Botanical Research Institute’s phosphate growth medium (NBRIP), and potato dextrose broth (PDB) media. MC-F2 demonstrated effective TCP dissolution across all media, and the highest final concentration of soluble phosphorus was observed in NBRIP medium. The solubilization was primarily driven by acidification through secretion of organic acids, notably gluconic and malic acid, leading to the formation of calcium oxalate hydrates (whewellite and weddellite) as secondary minerals. Untargeted metabolomics revealed that medium composition and TCP concentration significantly reshaped central metabolic pathways, particularly enhancing the TCA cycle in NBRIP, which directly underpinned the high organic acid production and superior solubilization performance. These findings not only expand the resources of phosphate-solubilizing fungi but also provide deeper metabolic insights into their environmental adaptability, highlighting the potential of Talaromyces sp. MC-F2 as a promising agent for developing eco-friendly biofertilizers.
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Data availability
The ITS rRNA gene sequence of *Talaromyces* sp. MC-F2 is available in GenBank under Accession Number PQ270042, accessible at [https://www.ncbi.nlm.nih.gov/nuccore/PQ270042.1/].
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This work was supported by the Fundamental Research Funds for the Central Universities (Grand NO. 2024QN11034).
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Mingchen Xia: Writing—original draft, Conceptualization, Visualization, Investigation, Formal analysis, Data curation, Funding acquisition. Peng Bao: Investigation, Methodology, Formal analysis, Data curation. Shilong He: Writing—review & editing. Guanzhou Qiu: Writing—review & editing. Weimin Zeng: Writing—review & editing. Yu He: Investigation.
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Xia, M., Bao, P., He, S. et al. A new isolated fungus Talaromyces sp. MC-F2 efficiently solubilizes phosphate through media-dependent metabolic regulation. Sci Rep (2026). https://doi.org/10.1038/s41598-026-44554-w
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DOI: https://doi.org/10.1038/s41598-026-44554-w
