From Pollen to Beebread: Reservoir of Potential Probiotic Yeasts

(1) Background: in this study, bee pollen, fresh and aged beebread, collected in the central Italy during the spring/summer 2024, were analysed as reservoir of potential new probiotic yeast strains. (2) Methods: culture dependent methods and molecular analyses were used to quantify and identify bacteria, molds and yeasts populations (3) Results: microbiological analyses of pollen showed a clear dominance of molds and bacteria over yeasts in all samples. In mature beebread the presence of lactic acid or other bacterial metabolites preserved the development of molds that were almost absent. As a general abundance, yeasts were about ten times less than bacteria, in particular the osmophilic yeasts were more abundant in pollen. Specifically, four yeast genera were identified in bee pollen, Cryptococcus, Starmerella, Bullera, Microstroma and five in the beebread, Starmerella, Zygosaccharomyces, Metschnikowia, Aureobasidium, Kodamaea and Moniliella. (4) Conclusions: out of 58 assayed yeasts, 9 strains exhibited the ability to resist to gastrointestinal physicochemical condition and 4 possessed all probiotic traits tested, demonstrating the effectiveness of pollen and beebread as natural source for new bioactive and functional yeasts.