Analysis of C-13-mixed triacylglycerol in stool by bulk (EA- IRMS) and compound specific (GC/MS) methods

Slater, C., Ling, S.C., Preston, T. and Weaver, L.T. (2002) Analysis of C-13-mixed triacylglycerol in stool by bulk (EA- IRMS) and compound specific (GC/MS) methods. Isotopes in Environmental and Health Studies, 38(2), pp. 79-86. (doi: 10.1080/10256010214220)

Abstract

This paper was presented in poster form at the 17th International Congress of Nutrition, August 27-31, Vienna, Austria (Annals of Nutrition and Metabolism 2001; 45(Suppl.1):349). Some of the data were also presented in poster form at the British Society of Gastroenterology Meeting, March 18-21, Glasgow, UK (Gut 2001; 48(Suppl.1):A91). The C-13- mixed triacylglycerol (MTG) breath test is used to measure intraluminal fat digestion. In normal digestion, 20-40% of the ingested C-13 label is recovered in breath CO2. We aimed to identify the proportions of ingested label excreted in stool, as well as breath following ingestion of C-13-MTG by children with impaired exocrine pancreatic function and healthy controls. C-13 enrichment of breath samples was measured by continuous flow isotope ratio mass spectrometry (IRMS) and cumulative percent dose recovered (cPDR) in 10 h was calculated. Total C-13 of a faecal fat extract from each stool was measured by elemental analyser-IRMS, and C-13 enrichment and concentration of the TBDMS derivative of octanoic acid was measured by GC/MS after hydrolysis of the fat extract. Stool 5- day cPDR was calculated. Mean breath cPDR was 35%. Mean cPDR in stool by combustion-IRMS and GC/ MS, respectively, was 0.8% and 1.0%. Therefore, the remaining 64% of the C-13 label must remain in the body and variability in breath cPDR is due to postabsorptive rather than predigestive factors.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Preston, Professor Tom
• Authors: Slater, C., Ling, S.C., Preston, T., and Weaver, L.T.
• Subjects: R Medicine > RC Internal medicine
• College/School: College of Science and Engineering > Scottish Universities Environmental Research Centre
• Journal Name: Isotopes in Environmental and Health Studies
• ISSN: 1025-6016