Potential bioactive peptides obtained after in vitro gastrointestinal digestion of wine lees from sequential fermentations

The biotechnological reuse of winery by-products has great potential to increase the value and sustainability of the wine industry. Recent studies revealed that yeast biomass can be an exciting source of bioactive peptides with possible benefits for human health, and its incorporation in plant-based foods is considered innovative and sustainable. In this study, we aimed to identify, through in silico analyses, potential bioactive peptides from yeast extracts after in vitro digestion. Wine lees from a non-Saccharomyces oenological yeast, Starmerella bacillaris FRI751, Saccharomyces cerevisiae EC1118, and sequential fermentation performed with both strains (SEQ) were recovered in a synthetic must. Cellular pellets were enzymatically treated with zymolyase, and the yeast extracts were submitted to in vitro gastrointestinal digestions. LC-MS/MS sequenced the hydrolyzed peptides, and their potential bioactivity was inferred. S. bacillaris FRI751 fermentation showed 132 peptide sequences, S. cerevisiae EC1118 60, SEQ 89. A total of 243 unique peptide sequences were identified across the groups. Furthermore, based on the peptide sequence, the FRI751 extract showed the highest potential antihypertensive with 275 bioactive fragments. Other bioactivities, such as antimicrobial and immunomodulatory, were also identified in all yeast extracts. A potential antiobesity bioactive peptide VVP was identified only in the yeast extract from S. bacillaris single strain. The wine lees from S. bacillaris single strain and SEQ fermentation are a richer source of potential bioactive peptides than those from S. cerevisiae fermentation. This study opens new possibilities in the valorization of winemaking by-products.