Development of the Analysis of Fecal Stanols in the Oyster Crassostrea gigas and Identification of Fecal Contamination in Shellfish Harvesting Areas

Harrault, Loïc; Jardé, Emilie; Jeanneau, Laurent; Petitjean, Patrice

Abstract

The objective of this work was to study the effects of washing and purification steps on qualitative and quantitative analysis of fecal stanols in the oyster Crassostrea gigas using either single or a combination of lipid purification steps on silica gel or aminopropyl bonded silica gel (NH2) or a washing step. Among the three analytical pathways compared, the two including water extraction or NH2 purification did not lead to higher recoveries and decreased repeatabilities of extractions compared to the single purification on silica gel. This latter led to similar recoveries (ca. 80 %) and repeatabilities (ca. 10 %) for both spiked standards (coprostanol and sitostanol). This analytical pathway has been applied to oysters collected in a harvesting area in Brittany (France) where fecal contaminations are important and allowed to quantify eight stanols in oysters. The relative proportions of fecal stanols of these oysters were combined with principal component analysis in order to investigate the usefulness of their stanol fingerprints to record a fecal contamination and to distinguish its source between human, porcine and bovine contaminations. Oysters non-fecally contaminated by Escherichia coli did not present specific stanol fingerprints while oysters fecally contaminated had a bovine fingerprint, suggesting a contamination of these samples by bovine sources. As a consequence, the method developed here allows the use of stanol fingerprints of oysters as a microbial source tracking tool that can be applied to shellfish harvesting areas subjected to fecal contaminations in order to identify the different sources of contamination and improve watershed management.

Citation

Harrault, L., Jardé, E., Jeanneau, L., & Petitjean, P. (2014). Development of the Analysis of Fecal Stanols in the Oyster Crassostrea gigas and Identification of Fecal Contamination in Shellfish Harvesting Areas. Lipids, 49(6), 597-607. https://doi.org/10.1007/s11745-014-3908-5

• Journal Article Type: Article
• Acceptance Date: Apr 3, 2014
• Online Publication Date: Apr 27, 2014
• Publication Date: 2014-06
• Deposit Date: Oct 10, 2017
• Journal: Lipids
• Print ISSN: 0024-4201
• Electronic ISSN: 1558-9307
• Publisher: Wiley
• Peer Reviewed: Peer Reviewed
• Volume: 49
• Issue: 6
• Pages: 597-607
• DOI: https://doi.org/10.1007/s11745-014-3908-5
• Public URL: https://durham-repository.worktribe.com/output/1347016