Chapter 5. Yeasts as Probiotics and their Functional Roles
Résumé
Several studies are focusing on yeasts as probiotics since they present several advantages over prokaryotic probiotic strains. Yeasts exert several positive effects on human health including immunomodulation, antimicrobial action against pathogens, trophic effect on the intestinal epithelium, positive effects on diarrheal diseases and enhancement of the intestinal epithelial barrier. Other beneficial functions of yeasts are biodegradation of phytate, folate biofortification and absorption/degradation of mycotoxins. However, only formulations based on Saccharomyces boulardii and Kluyveromyces spp. are commercially available. This chapter offers an overview concerning the probiotic features and physiological characteristics of S. boulardii . It summarizes the mechanisms of action of yeast probiotics and their benefits for human health. It also shows the importance of encapsulation to improve the efficacy of yeast probiotics and the relevance of further studies to improve probiotic traits exploiting engineered yeasts.