Probiotic potential of Saccharomyces cerevisiae GILA with alleviating intestinal inflammation in a dextran sulfate sodium induced colitis mouse model

Recently, several probiotic products have been developed; however, most probiotic applications focused on prokaryotic bacteria whereas eukaryotic probiotics have received little attention. Saccharomyces cerevisiae yeast strains are eukaryotes notable for their fermentation and functional food applications. The present study investigated the novel yeast strains isolated from Korean fermented beverages and examined their potential probiotic characteristics. We investigated seven strains among 100 isolates with probiotic characteristics further. The strains have capabilities such as auto-aggregation tendency, co-aggregation with a pathogen, hydrophobicity with n-hexadecane,1,1-diphenyl-2-picrylhydrazyl scavenging effect, survival in simulated gastrointestinal tract conditions and the adhesion ability of the strains to the Caco-2 cells. Furthermore, all the strains contained high cell wall glucan content, a polysaccharide with immunological effects. Internal transcribed spacer sequencing identified the Saccharomyces strains selected in the present study as probiotics. To examine the effects of alleviating inflammation in cells, nitric oxide generation in raw 264.7 cells with S. cerevisiae showed that S. cerevisiae GILA could be a potential probiotic strain able to alleviate inflammation. Three probiotics of S. cerevisiae GILA strains were chosen by in vivo screening with a dextran sulfate sodium-induced colitis murine model. In particular, GILA 118 down-regulates neutrophil-lymphocyte ratio and myeloperoxidase in mice treated with DSS. The expression levels of genes encoding tight junction proteins in the colon were upregulated, cytokine interleukin-10 was significantly increased, and tumor necrosis factor-alpha was reduced in the serum.

Automated summary

Recently, eukaryotic probiotics, particularly Saccharomyces cerevisiae yeast strains, have gained less attention compared to prokaryotic probiotics. In this study, novel yeast strains isolated from Korean fermented beverages were investigated for their potential probiotic characteristics. The selected strains showed various capabilities such as aggregation tendencies, co-aggregation with pathogens, hydrophobicity, antioxidant effects, survival in simulated gastrointestinal conditions, and adhesion to intestinal cells. Moreover, these strains had high cell wall glucan content and were confirmed as probiotics through genetic analysis. Additionally, S. cerevisiae strain GILA exhibited anti-inflammatory effects in both in vitro and in vivo experiments, suggesting its potential as a therapeutic probiotic for inflammation-related diseases.