Metabolomics
STERILE, SEPARATION, RESOLUTION
Frozen aliquots of urine were thawed prior to normalisation through dilution with sterile distilled water to the lowest specific gravity measured by refractometry as previously described [For faecal water, frozen aliquots of sample were thawed before centrifugation at 18,000Hydrophilic liquid interaction chromatography (HILIC) metabolite profiling of the urine and faecal water samples was performed on a Vanquish Liquid Chromatography chromatographic separation system connected to an IDX High Resolution Mass Spectrometer (Thermo Scientific). The HILIC positive and negative data sets were processed via Compound Discoverer 3.2 according to the following settings: untargeted metabolomic workflow with online database: mass tolerance 10 ppm, maximum shift 0.3 min, alignment model adaptive curve, minimum intensity 500 K, S/N threshold 3, compound consolidation, mass tolerance 10 ppm, RT tolerance 0.3 min. Database matching was performed at MS2 level using Thermo scientific m/z cloud with a similar index of 80% or better.