Metabolites characterisation of colon content samples from mouse treated with or without κ-carrageenan using LC–MS-based method

Untargeted metabolomics analysis was conducted using colon contents from mice. Briefly, individual samples were accurately weighed. After the precipitation of proteins with methanol, the extracted metabolites from the samples were characterized by an Ultra-performance liquid chromatography (UPLC) tandem mass spectrometer (UPLC-MS/MS), consisting of a Vanquish UHPLC system (ThermoFisher, Germany) coupled with an Orbitrap Q ExactiveTMHF-X mass spectrometer (Thermo Fisher，Germany). The raw data were processed using the Compound Discoverer 3.1 (CD3.1, ThermoFisher) to perform peak alignment, peak picking, and quantitation for each metabolite. And then peaks were matched with the mzCloud (https://www.mzcloud.org/), mzVault and MassList database to obtain the accurate qualitative and relative quantitative results.