Analysis of short chain fatty acids in faecal samples
Short chain fatty acids (SCFA) are produced by the gut microflora following the intake of complex carbohydrates and have been suggested as a contributor for some of the health benefits associated with dietary fibre (DF) intake. For further research of the mechanisms and effects of SCFA, reliable and...
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| Formato: | First cycle, G2E |
| Lenguaje: | Inglés Inglés |
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2016
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| Acceso en línea: | https://stud.epsilon.slu.se/9845/ |
| _version_ | 1855571591869497344 |
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| author | Ewald, Nils |
| author_browse | Ewald, Nils |
| author_facet | Ewald, Nils |
| author_sort | Ewald, Nils |
| collection | Epsilon Archive for Student Projects |
| description | Short chain fatty acids (SCFA) are produced by the gut microflora following the intake of complex carbohydrates and have been suggested as a contributor for some of the health benefits associated with dietary fibre (DF) intake. For further research of the mechanisms and effects of SCFA, reliable and accurate methods for analysis of SCFA in different biological samples are needed. In this project the aim was to develop and validate a rapid and ease-of use method for analysis of SCFA content in faecal samples. The contents of acetic, propionic, iso-butyric, n-butyric, iso-valeric, n-valeric and capronic acid were analysed through a method where fecal water was obtained through centrifugation and SCFA were further extracted with propyl formate. Extracts were analysed on a gas chromatograph coupled with a flame-ionization detector (GC-FID). The method was validated including estimation of accuracy and precision which were measured through calculation of recovery, deviation from linearity and by the coefficient of variance (CV), respectively. An exploratory test was also performed to analyse the distribution of SCFA in faecal matter. Moreover, the method was used to analyse SCFA concentrations in faecal samples (n=40) from two Norwegian bowel cancer projects, NORCCAP and BCSN. The results of the validation (recovery, CV and deviation from linearity) varied somewhat between the three batches, and thereby also the limits of quantification (LOQ), which were limited, but in most cases included the physiologically relevant concentrations. Through the exploratory distribution test, a significant difference in SCFA content was found between the in- and outside of the faecal sample, which emphasises the importance of homogenization of samples or consistent sampling from faecal samples. SCFA contents of faecal samples from the NORCCAP and BCSN samples were consistent with those reported by other studies, which indicate that the method produces reliable results. For a higher accuracy and precision, it is suggested that the amount of faecal material analysed is increased, followed by further validation of both lower and higher concentrations. Additionally, the effects of storage with and without buffer should also be investigated for more comparable results. |
| format | First cycle, G2E |
| id | RepoSLU9845 |
| institution | Swedish University of Agricultural Sciences |
| language | Inglés Inglés |
| publishDate | 2016 |
| publishDateSort | 2016 |
| record_format | eprints |
| spelling | RepoSLU98452016-11-30T12:50:37Z https://stud.epsilon.slu.se/9845/ Analysis of short chain fatty acids in faecal samples Ewald, Nils Physiology of human nutrition Short chain fatty acids (SCFA) are produced by the gut microflora following the intake of complex carbohydrates and have been suggested as a contributor for some of the health benefits associated with dietary fibre (DF) intake. For further research of the mechanisms and effects of SCFA, reliable and accurate methods for analysis of SCFA in different biological samples are needed. In this project the aim was to develop and validate a rapid and ease-of use method for analysis of SCFA content in faecal samples. The contents of acetic, propionic, iso-butyric, n-butyric, iso-valeric, n-valeric and capronic acid were analysed through a method where fecal water was obtained through centrifugation and SCFA were further extracted with propyl formate. Extracts were analysed on a gas chromatograph coupled with a flame-ionization detector (GC-FID). The method was validated including estimation of accuracy and precision which were measured through calculation of recovery, deviation from linearity and by the coefficient of variance (CV), respectively. An exploratory test was also performed to analyse the distribution of SCFA in faecal matter. Moreover, the method was used to analyse SCFA concentrations in faecal samples (n=40) from two Norwegian bowel cancer projects, NORCCAP and BCSN. The results of the validation (recovery, CV and deviation from linearity) varied somewhat between the three batches, and thereby also the limits of quantification (LOQ), which were limited, but in most cases included the physiologically relevant concentrations. Through the exploratory distribution test, a significant difference in SCFA content was found between the in- and outside of the faecal sample, which emphasises the importance of homogenization of samples or consistent sampling from faecal samples. SCFA contents of faecal samples from the NORCCAP and BCSN samples were consistent with those reported by other studies, which indicate that the method produces reliable results. For a higher accuracy and precision, it is suggested that the amount of faecal material analysed is increased, followed by further validation of both lower and higher concentrations. Additionally, the effects of storage with and without buffer should also be investigated for more comparable results. Kortkedjiga fettsyror produceras av tarmfloran efter intag av komplexa kolhydrater och har föreslagits som en bidragande förklaring till några av de hälsofördelar som förknippats med intag av kostfibrer. För vidare studier kring mekanismerna och effekterna av kortkedjiga fettsyror krävs pålitliga och precisa metoder för analys av kortkedjiga fettsyror i olika biologiska prover. I detta projekt var syftet att utveckla och validera en enkel och snabb metod för analys av kortkedjiga fettsyror i avföringsprover. Innehållet av ättik-, propan-, isobutan-, butan-, isovalerian-, valerian- och kapronsyra analyserades genom centrifugering, extrahering med propylformat och analys med gaskromatografi och flamjonisationsdetektor (GC-FID). Metoden validerades genom mätning av noggrannhet och precision som räknades ut i form av utbyte, avvikelse från standardlinje och variationskoefficient (CV). Ett ytterligare test utfördes för att undersöka hur koncentrationen av kortkedjiga fettsyror varierade i olika delar av ett avföringsprov. Dessutom användes metoden för att analysera innehållet av kortkedjiga fettsyror i prover (n=40) från två norska tarmcancerprojekt, NORCCAP och BCSN. Resultaten från valideringen (utbyte, variationskoefficient och avvikelse från standardlinjen) varierade mellan de tre omgångarna och därmed även gränserna för kvantifiering, vilka var begränsade men i de flesta fallen inkluderade de koncentrationer av kortkedjiga fettsyror som är fysiologiskt relevanta. Testet som undersökte variationen av kortkedjiga fettsyror uppvisade signifikanta skillnader mellan in- och utsidan av avföringsprovet, vilket understryker vikten av homogenisering av prover och att vara konsekvent vid provtagning av avföringsprover. De koncentrationer som uppmättes från NORCCAP- och BCSN- proverna stämde väl överens med de som rapporterats i tidigare studier, vilket indikerar att metoden ger tillförlitliga resultat. För att uppnå högre precision och noggrannhet bör mängden avföring som analyseras ökas samt en ytterligare validering på både lägre och högre koncentrationer utföras. Dessutom bör effekterna av lagring med och utan buffert undersökas för mer jämförbara resultat. 2016-11-29 First cycle, G2E NonPeerReviewed application/pdf en https://stud.epsilon.slu.se/9845/1/ewald_n_161130.pdf Ewald, Nils, 2016. Analysis of short chain fatty acids in faecal samples : development and validation of a new method. First cycle, G2E. Uppsala: (NL, NJ) > Dept. of Food Science <https://stud.epsilon.slu.se/view/divisions/OID-550.html> urn:nbn:se:slu:epsilon-s-6101 eng |
| spellingShingle | Physiology of human nutrition Ewald, Nils Analysis of short chain fatty acids in faecal samples |
| title | Analysis of short chain fatty acids in faecal samples |
| title_full | Analysis of short chain fatty acids in faecal samples |
| title_fullStr | Analysis of short chain fatty acids in faecal samples |
| title_full_unstemmed | Analysis of short chain fatty acids in faecal samples |
| title_short | Analysis of short chain fatty acids in faecal samples |
| title_sort | analysis of short chain fatty acids in faecal samples |
| topic | Physiology of human nutrition |
| url | https://stud.epsilon.slu.se/9845/ https://stud.epsilon.slu.se/9845/ |