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 < 5 ppm or 10 ppm) and matching experimental MS/MS fragmentation patterns against libraries.
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.
"],"repository":["MetaboLights"],"study_status":["Public"],"ptm_modification":[""],"instrument_platform":["Liquid Chromatography MS - negative - reverse-phase","Liquid Chromatography MS - positive - reverse-phase"],"chromatography_protocol":["Pooled Quality Control (QC) Samples: 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.
"],"publication":["Untargeted metabolomic profiling of the gut microbiota during senescence in the Chinese giant salamander (Andrias davidianus)."],"submitter_affiliation":["Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai)"],"submitter_name":["Shuhan Zhang"],"organism_part":["feces"],"technology_type":["mass spectrometry assay"],"disease":[""],"extraction_protocol":["Fecal samples from A. davidianus 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.
"],"organism":["Andrias davidianus"],"full_dataset_link":["https://www.ebi.ac.uk/metabolights/MTBLS14860"],"author":["Shuhan 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."],"data_transformation_protocol":["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.
"],"study_factor":["Development stage","Sample metabo name"],"submitter_email":["z302915732@163.com"],"sample_collection_protocol":["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.
"],"omics_type":["Metabolomics"],"study_design":["Metabolomics","Thermo Fisher LTQ","untargeted analysis","Thermo Scientific Vanquish Flex UHPLC System","Aging","Andrias davidianus","experimental blank","case-control design","feces","untargeted metabolite profiling"],"curator_keywords":["Metabolomics","Thermo Fisher LTQ","untargeted analysis","Thermo Scientific Vanquish Flex UHPLC System","Aging","Andrias davidianus","experimental blank","case-control design","feces","untargeted metabolite profiling"],"mass_spectrometry_protocol":["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.
"],"additional_accession":[]},"is_claimable":false,"name":"Untargeted metabolomic profiling of the gut microbiota during senescence in the Chinese giant salamander (Andrias davidianus)","description":"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.","dates":{"publication":"2026-07-06","submission":"2026-06-26"},"accession":"MTBLS14860","cross_references":{}}