Volume: 5, 2026
5th International PhD Students’ Conference at the University of Life Sciences in Lublin, Poland:
ENVIRONMENT – PLANT – ANIMAL – PRODUCT
Abstract number: H023
DOI: https://doi.org/10.24326/ICDSUPL5.H023
Published online: 22 April 2026
Probiotic potentials of Staphylococcus epidermidis: a safety assessment
Kinga Zdybel*, Angelika Śliwka and Adam Waśko
Department of Biotechnology, Microbiology and Human Nutrition, University of Life Sciences in Lublin, 8 Skromna St., 20-704 Lublin, Poland
* Corresponding author: kinga.zdybel@up.edu.pl
Probiotics, defined as live microorganisms that confer beneficial effects on the host, are integral to maintaining intestinal homeostasis and modulating immune responses. Recent years have witnessed an expansion in research on novel strains with probiotic potential, particularly focusing on microorganisms derived from the natural human microbiota. These investigations encompass not only traditional probiotics, such as Lactobacillus and Bifidobacterium, but also lesser-known species with potential functional and adaptive properties. A promising candidate is Staphylococcus epidermidis, a common commensal of human skin, which may exhibit beneficial functional properties. Some studies have suggested that strains originating from the natural microbiota can support microbial balance, modulate immune responses, and engage in beneficial interactions with other host microorganisms. Despite the generally recognised safety of well-characterized species, each new strain with probiotic potential necessitates thorough safety evaluation because of the possibility of causing infections, modulating immune responses, or participating in horizontal gene transfer.
In this study, the probiotic potential and safety of eight S. epidermidis isolates obtained from ten human milk samples were evaluated, with particular attention to their functional properties and the presence of potential risk factors. The analysed isolates displayed diverse safety profiles and functional characteristics. Three isolates exhibited α-hemolysis, while the remaining five showed γ-hemolysis. Gelatinase activity was not detected in any of the tested strains. Most isolates were resistant to vancomycin and clindamycin, whereas they were mostly sensitive to other antibiotics. Functional characterisation of five isolates after safety testing revealed varied probiotic properties. Cell surface hydrophobicity ranged from approximately 50% to over 80%. All tested strains survived at pH 4 and pH 7, while no survival was observed at pH 2 and pH 3. Moreover, autoaggregation increased over time, reaching values above 80–90% after 24 h in selected isolates.
The results indicate that five of the analysed S. epidermidis isolates met the safety criteria and can be considered potentially safe. These selected isolates exhibited beneficial functional properties, including high autoaggregation capacity, appropriate cell surface hydrophobicity, and tolerance to moderately acidic conditions, despite the lack of survival in strongly acidic environments, such as pH 2 and pH 3. These findings underscore the importance of a multi-step evaluation of strain safety and functionality and suggest the potential for further research into their application as probiotics.
Keywords: human milk; microbiota; probiotics; safety; Staphylococcus
How to cite
Zdybel K., Śliwka A., Waśko A., 2026. Probiotic potentials of Staphylococcus epidermidis: a safety assessment. In: 5th International PhD Students’ Conference at the University of Life Sciences in Lublin, Poland: Environment – Plant – Animal – Product. https://doi.org/10.24326/ICDSUPL5.H023