biostudies-literatureUjszegi JMinistry of Innovation and TechnologyNational Research and Innovation Office of Hungarye0082625https://www.ebi.ac.uk/biostudies/studies/S-EPMC12403624biostudies-literatureUnknown13(9)Survival of amphibian assemblages is threatened by many factors. Among them, chytridiomycosis, the disease caused by the chytrid fungus <i>Batrachochytrium dendrobatidis</i> (Bd), has great importance, also threatening populations of the yellow-bellied toad (<i>Bombina variegata</i>), which has a scattered, isolated distribution in Hungary. Treatment with secondary metabolites of the entomopathogenic bacterium <i>Xenorhabdus szentirmaii</i> is a promising method in the mitigation of chytridiomycosis, as recently demonstrated. To assess whether it may also be effective for lowering infection intensities in <i>B. variegata</i> tadpoles, we extracted cell-free culture media (CFCM) from liquid cultures of <i>X. szentirmaii</i> and tested their antifungal efficacy at a dilution of 0.1% (v/v), wMicrobiology spectrumMitigation of chytridiomycosis on &lt;i&gt;Bombina variegata&lt;/i&gt; tadpoles with the antimicrobial metabolites of the bacterium &lt;i&gt;Xenorhabdus szentirmaii&lt;/i&gt;.PMC12403624PD-142654ÚNKP-23-6ÚNKP-23-4, EKÖP-24-4ÚNKP-22-3, ÚNKP-23-4Toth AGUjszegi JMagos GVoros JBoros ZHarmos KKasler AfalseMitigation of chytridiomycosis on &lt;i&gt;Bombina variegata&lt;/i&gt; tadpoles with the antimicrobial metabolites of the bacterium &lt;i&gt;Xenorhabdus szentirmaii&lt;/i&gt;.Survival of amphibian assemblages is threatened by many factors. Among them, chytridiomycosis, the disease caused by the chytrid fungus <i>Batrachochytrium dendrobatidis</i> (Bd), has great importance, also threatening populations of the yellow-bellied toad (<i>Bombina variegata</i>), which has a scattered, isolated distribution in Hungary. Treatment with secondary metabolites of the entomopathogenic bacterium <i>Xenorhabdus szentirmaii</i> is a promising method in the mitigation of chytridiomycosis, as recently demonstrated. To assess whether it may also be effective for lowering infection intensities in <i>B. variegata</i> tadpoles, we extracted cell-free culture media (CFCM) from liquid cultures of <i>X. szentirmaii</i> and tested their antifungal efficacy at a dilution of 0.1% (v/v), w2025-01-01T00:00:00Z2025 Sep2026-05-29T17:21:01.084Z2026-04-08T05:33:38.884ZS-EPMC124036244075786710.1128/spectrum.00826-25