MetaboLightsapplication/xmlftp://ftp.ebi.ac.uk/pub/databases/metabolights/studies/public/MTBLS14860/m_MTBLS14860_LC-MS_positive_reverse-phase_v2_maf.tsvftp://ftp.ebi.ac.uk/pub/databases/metabolights/studies/public/MTBLS14860/m_MTBLS14860_LC-MS_negative_reverse-phase_v2_maf.tsvftp://ftp.ebi.ac.uk/pub/databases/metabolights/studies/public/MTBLS14860/i_Investigation.txtftp://ftp.ebi.ac.uk/pub/databases/metabolights/studies/public/MTBLS14860/a_MTBLS14860_LC-MS_negative_reverse-phase.txtftp://ftp.ebi.ac.uk/pub/databases/metabolights/studies/public/MTBLS14860/a_MTBLS14860_LC-MS_positive_reverse-phase.txtftp://ftp.ebi.ac.uk/pub/databases/metabolights/studies/public/MTBLS14860/s_MTBLS14860.txtprimaryOK200ftp://ftp.ebi.ac.uk/pub/databases/metabolights/studies/public/MTBLS14860<p>Identification Criteria: Metabolite identification was performed in accordance with the Metabolomics Standards Initiative (MSI) guidelines. Level 1 annotations were confirmed using internal standard tracking (when available). Level 2 (putative) identification was established based on accurate precursor mass (m/z tolerance &lt; 5 ppm or 10 ppm) and matching experimental MS/MS fragmentation patterns against libraries.</p><p>Reference Databases: Features were cross-referenced and annotated using public spectral matching databases, including KEGG (Kyoto Encyclopedia of Genes and Genomes), HMDB (Human Metabolome Database), and METLIN.</p>MetaboLightsPublicLiquid Chromatography MS - negative - reverse-phaseLiquid Chromatography MS - positive - reverse-phase<p><strong>Pooled Quality Control (QC) Samples: </strong>Prepared by mixing equal aliquots (e.g., 10 $\mu$L) from every individual fecal extract. QC samples were injected at the beginning of the run to equilibrate the system and periodically (every 8-10 sample injections) throughout the analytical batch to monitor instrument stability and retention time drift.</p>Untargeted metabolomic profiling of the gut microbiota during senescence in the Chinese giant salamander (Andrias davidianus).Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai)Shuhan Zhangfecesmass spectrometry assay<p>Fecal samples from <em>A. davidianus</em> were thawed on ice. An aliquot of each sample (e.g., 50 mg) was mixed with a pre-cooled extraction solvent (methanol:acetonitrile:water, 2:2:1, v/v/v). The mixture was vortexed vigorously for 1 min, homogenized at high speed (e.g., 60 Hz for 2 min), and then sonicated in an ice-water bath for 10 min. To fully precipitate proteins, the samples were incubated at -20°C for 1 hour, followed by centrifugation at 14,000 g at 4°C for 15 min. The resulting supernatant was collected, evaporated to dryness using a vacuum concentrator, and reconstituted in an acetonitrile:water (1:1, v/v) solution prior to LC-MS injection.</p>Andrias davidianushttps://www.ebi.ac.uk/metabolights/MTBLS14860Shuhan Zhang. Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai). z302915732@163.com.Yan qingyun. Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai). yanqingyun@sml-zhuhai.cn.<p>Vendor-specific raw data files (e.g., .raw, .d) were converted into the open-source .mzML format using the ProteoWizard MSConvert software pipeline (version 3.0), utilizing peak picking and centroiding filters.</p>Development stageSample metabo namez302915732@163.com<p>Gut content and fecal samples were collected from non-elderly and elderly Chinese giant salamanders (Andrias davidianus) during senescence. Samples were immediately frozen in liquid nitrogen and stored at -80 degrees Celsius until extraction.</p>MetabolomicsMetabolomicsThermo Fisher LTQuntargeted analysisThermo Scientific Vanquish Flex UHPLC SystemAgingAndrias davidianusexperimental blankcase-control designfecesuntargeted metabolite profilingMetabolomicsThermo Fisher LTQuntargeted analysisThermo Scientific Vanquish Flex UHPLC SystemAgingAndrias davidianusexperimental blankcase-control designfecesuntargeted metabolite profiling<p>Liquid chromatography was performed on an [Insert Instrument Make/Model, e.g., Thermo Scientific Vanquish UHPLC / Waters ACQUITY UPLC] system. Chromatographic separation was achieved using a [Insert Column Name, e.g., Waters ACQUITY UPLC BEH C18 Column (2.1 mm $\times$ 100 mm, 1.7 $\mu$m)] maintained at a constant temperature of 40°C.</p>falseUntargeted metabolomic profiling of the gut microbiota during senescence in the Chinese giant salamander (Andrias davidianus)Untargeted metabolomic profiling of the gut microbiota in Andrias davidianus. Combining non-elderly and elderly cohorts, this study reveals significant alterations in gut carbohydrate metabolites during Aging, reflecting a functional erosion of microbial processing capacity as a key hallmark of vertebrate aging.2026-07-062026-06-26MTBLS14860