Survivability of Kluyveromyces marxianus Isolated From Korean Kefir in a Simulated Gastrointestinal Environment

accounts for > 90% of the yeast population of kefir, and recently, its probiotic potential has been actively explored with a focus on its health benefits and safety. Herein, the survivability of five kefir-isolated strains (Km A1-A5) in a simulated gastrointestinal (GI) environment was evaluated and compared with those of commercial probiotic yeast, MYA-796. To further explore the potential to survive in the host GI tract, biochemical activities, hydrophobicity assay, biofilm formation, auto-aggregation analysis, and phenol tolerance of the strains were assessed. A4 exhibited the best survivability among all tested strains, including the clinically proven probiotic yeast strain MYA-796 ( = 0.014) in the artificial GI tract ranging from pH 2.0 to 7.5. In addition, the five strains and MYA-796 displayed different assimilation of lactose, xylitol, D-sorbitol, and DL-lactate, indicating that metabolized a wide range of substances and, thus, might be more feasible to nourish themselves in the host GI tract for survival. strains showed a greater hydrophobicity of cell surface, abilities to biofilm formation and auto-aggregation, and phenol tolerance than MYA-796, suggesting greater potential for survival in the host GI tract.