In Vitro Properties of Potential Probiotic Indigenous Yeasts Originating from Fermented Food and Beverages in Taiwan

Probiotics are live microorganisms that may be able to help prevent and treat some illnesses. Most probiotics on the market are bacterial, primarily Lactobacillus. Yeast are an inevitable part of the microbiota of various fermented foods and beverages and have several beneficial properties that bacteria do not have. In this study, yeast strains were isolated from fermented food and beverages. Various physiological features of the candidate probiotic isolates were preliminarily investigated, including bile salt and acid tolerance, cell surface hydrophobicity, autoaggregation, antioxidant activity, and β-galactosidase activity. Several yeast strains with probiotic potential were selected. Overall, Kluyveromyces marxianus JYC2614 adapted well to the bile salt and acid tolerance test; it also had favorable autoaggregation and good cell-surface hydrophobicity. Klu. marxianus JYC2610 grew well according to the bile salt and acid tolerance test and performed well regarding cell surface hydrophobicity and β-galactosidase activity. Selected yeast species can survive in a gastrointestinal environment and should be further evaluated in vivo as probiotics in the future. Our findings should encourage further studies on the application of the strains in this study as food and feed supplements.