Isolation, identification and in vitro probiotic characterisation of yeast strains found in fermented turnip juice.

Unlabelled: The probiotic characteristics of yeasts isolated from fermented turnip juices collected from different cities of Türkiye were investigated. Most of the isolates were identified as (45%), (20%), (15%) and (12.5%). Regarding their probiotic properties, all strains showed viability at pH 3 and 4, and 24 strains belonging to , and were tolerant to pH 2, 3 and 4. All strains showed tolerance to bile salts (55.92-139.17%), phenol (43.88-130.46%), pepsin (66.32-111.70%) and pancreatin (86.19-116.10%). The proteolytic activity of all but 4 strains ranged from 0.001 to 0.077 mg tyrosine/mL, and they did not exhibit β-galactosidase activity. All strains were viable in the presence of 1.5% NaCl, and approximately 60% were viable in the presence of 10% NaCl. Their cell surface hydrophobicity towards xylene varied between 1.53% and 56.22%. LM4 showed the highest hydrophobicity. The auto-aggregation of the strains varied from 23.01 to 63.91%, while the co-aggregation ability with Typhimurium varied from 1.64 to 51.69%, with significant differences between the strains. Thus, the yeast strains from fermented turnip juice exhibit probiotic potential and can be used to develop new probiotic food products or supplements.

Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-024-06143-5.