Anti-inflammatory compounds in probiotic yeast revealed by untargeted metabolomics

<strong>Abstract</strong> The saccharomyces strain <em>Saccharomyces cerevisiae </em>var.<em> boulardii</em> has exhibited efficacy in ameliorating symptoms of gastrointestinal disorders, including inflammatory diseases. The molecular origin of the anti-inflammatory activity has remained largely elusive to this day. Earlier studies suggest a small, secreted, yet undefined, molecule as the active principle and thus an untargeted metabolomics approach towards its identification was adopted. We used LCMS-analysis to interrogate the secreted metabolome of <em>S. cerevisiae </em>var.<em> boulardii</em> in comparison to a <em>S. cerevisiae </em>reference strain. Statistical analysis of the data revealed several compounds unique to <em>S. cerevisiae </em>var.<em> boulardii</em>, that were partially annotated and confirmed by comparison with authentic standards. Furthermore, anti-inflammatory properties were experimentally assigned to several small molecules, indicating that this property of the yeast variant is due to several factors. Our data suggest that the anti-inflammatory properties of <em>S. cerevisiae </em>var.<em> boulardii</em> can be linked to the activity of small molecules in its secreted metabolome.