evaluation of probiotic, antifungal, and antioxidant properties of the predominant yeast isolated from acorn sourdough

There is always the possibility of encountering probiotic yeasts with functional capabilities in natural habitats that have been less studied. in the present study, the predominant yeast from acorn sourdough was isolated and identified using pcr. the probiotic properties of the isolate, as well as its antifungal and antioxidant activities were also investigated. sequencing results of pcr products led to the identification of pichia kudriavzevii as the predominant yeast isolate. the survival rate of the isolate in simulated gastrointestinal conditions was 91.93%. the auto-aggregation ability of the isolate was equal to 84.65%, and its hydrophobicity against hexane and xylene was 35.15% and 21.70%, respectively. the antibacterial activity of p. kudriavzevii studied in this research against listeria monocytogenes was 85.58%, which was significantly (p<0.05) higher than other studied foodborne bacteria. however, the co-aggregation ability of the yeast isolate against tested pathogens showed no significant difference. furthermore, the isolate showed no hemolytic activity, and it was resistant to all tested antibiotics, but showed relative sensitivity to the antimycotic agents including itraconazole, ketoconazole, and natamycin, while being resistant to potassium sorbate. the antifungal activity of the isolate against a. flavus was also confirmed, with antioxidant activity measured at 78.67%. accordingly, p. kudriavzevii yeast isolate can be introduced as a suitable candidate for use as a probiotic and/or protective culture in fermentation industries. 

evaluation of probiotic, antifungal, and antioxidant properties of the predominant yeast isolated from acorn sourdough

there is always the possibility of encountering probiotic yeasts with functional capabilities in natural habitats that have been less studied. in the present study, the predominant yeast from acorn sourdough was isolated and identified using pcr. the probiotic properties of the isolate, as well as its antifungal and antioxidant activities were also investigated. sequencing results of pcr products led to the identification of pichia kudriavzevii as the predominant yeast isolate. the survival rate of the isolate in simulated gastrointestinal conditions was 91.93%. the auto-aggregation ability of the isolate was equal to 84.65%, and its hydrophobicity against hexane and xylene was 35.15% and 21.70%, respectively. the antibacterial activity of p. kudriavzevii studied in this research against listeria monocytogenes was 85.58%, which was significantly (p<0.05) higher than other studied foodborne bacteria. however, the co-aggregation ability of the yeast isolate against tested pathogens showed no significant difference. furthermore, the isolate showed no hemolytic activity, and it was resistant to all tested antibiotics, but showed relative sensitivity to the antimycotic agents including itraconazole, ketoconazole, and natamycin, while being resistant to potassium sorbate. the antifungal activity of the isolate against a. flavus was also confirmed, with antioxidant activity measured at 78.67%. accordingly, p. kudriavzevii yeast isolate can be introduced as a suitable candidate for use as a probiotic and/or protective culture in fermentation industries.