Up-scalable approaches for yeast mannan oligosaccharides (MOS) production: characterization and immunomodulatory properties

Mannan oligosaccharides (MOS) are widely used as feed additives due to their effects on gut microbiome modulation. Its application in the nutraceutical and functional food industries is also increasing. Numerous studies portraying MOS production from beta-mannans can be found, but its production from yeast mannans is barely explored. Herein, two up-scalable approaches to produce yeast-derived MOS are presented: hydrothermal and acidic processing. Process efficiency was evaluated, and the resulting extracts were characterized (ATR-FT-IR, PXRD, SEM, MWD, DSC, sugar, and protein content). Extracts were also evaluated for their cytotoxicity and immunomodulatory effect; furthermore, a simulated gastrointestinal tract digestion was performed to confirm their biological potential. The hydrothermal process resulted in the highest yield, whereas the acidic process resulted in lower molecular weight populations. Immunomodulatory results indicate that MOS digested extracts do not hold anti-inflammatory activity but grant an immunostimulant effect, whereas the non-digested MOS acidic extract showed an anti-inflammatory potential. This work provides valuable contributions towards the industrial production of yeast-derived MOS extracts, highlighting their potential for applications in various fields while contributing to a circular economy approach.