title: Antioxidant properties and global metabolite screening of the probiotic yeast Saccharomyces cerevisiae var. boulardii.
abstract: BACKGROUND
  Saccharomyces cerevisiae var. boulardii is the only yeast species with probiotic properties. It is considered to have therapeutic significance in gastrointestinal disorders. In the present study, a comparative physiological study between this yeast and Saccharomyces cerevisiae (BY4742) was performed by evaluating two prominent traits of probiotic species, responses to different stress conditions and antioxidant capacity. A global metabolite profile was also developed aiming to identify which therapeutically important secondary metabolites are produced.
  
  
  RESULTS
  Saccharomyces cerevisiae var. boulardii showed no significant difference in growth patterns but greater stress tolerance compared to S. cerevisiae. It also demonstrated a six- to 10-fold greater antioxidant potential (judged by the 1,1-diphenyl-2-picrylhydrazyl assay), with a 70-fold higher total phenolic content and a 20-fold higher total flavonoid content in the extracellular fraction. These features were clearly differentiated by principal component analysis and further indicated by metabolite profiling. The extracellular fraction of the S. cerevisiae var. boulardii cultures was found to be rich in polyphenolic metabolites: vanillic acid, cinnamic acid, phenyl ethyl alcohol (rose oil), erythromycin, amphetamine and vitamin B6, which results in the antioxidant capacity of this strain.
  
  
  CONCLUSIONS
  The present study presents a new perspective for differentiating the two genetically related strains of yeast, S. cerevisiae and S. cerevisiae var. boulardii by assessing their metabolome fingerprints. In addition to the correlation of the phenotypic properties with the secretory metabolites of these two yeasts, the present study also emphasizes the potential to exploit S. cerevisiae var. boulardii in the industrial production of these metabolites. © 2016 Society of Chemical Industry.
authors.affiliation: Food Engineering and Technology Department, Institute of Chemical Technology (ICT), Matunga, Mumbai, 400 019, India.|School of Biological Sciences, Queen's University Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast, BT9 7BL, UK.
authors.forename: Suprama
authors.initials: S
authors.lastname: Datta
authors.affiliation: School of Biological Sciences, Queen's University Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast, BT9 7BL, UK.|School of Pharmacy and Biomolecular Sciences, University of Brighton, Huxley Building, Lewes Road, Brighton, Sussex, BN2 4GJ, UK.
authors.forename: David J
authors.identifier: http://orcid.org/0000-0002-0985-8818
authors.initials: DJ
authors.lastname: Timson
authors.affiliation: Food Engineering and Technology Department, Institute of Chemical Technology (ICT), Matunga, Mumbai, 400 019, India.
authors.forename: Uday S
authors.initials: US
authors.lastname: Annapure
mesh_terms: D000975:Antioxidants / Q000737:chemistry* / Q000378:metabolism; D005419:Flavonoids / Q000737:chemistry* / Q000378:metabolism; D019936:Probiotics / Q000737:chemistry* / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000737:chemistry* / Q000378:metabolism; D064210:Secondary Metabolism
chemical_list: D000975:Antioxidants; D005419:Flavonoids
keywords: Saccharomyces cerevisiae BY4742; Saccharomyces cerevisiae var. boulardii NCYC 3264; antioxidant capacity; global metabolite profiling; probiotic; stress-tolerance