The vaginal microbiota plays a key role in maintaining women's health, with dominant bacteria of the genus Lactobacillus maintaining an acidic pH and inhibiting the growth of pathogenic microorganisms. A reduced presence of lactobacilli is associated with an increased incidence of vaginal infections, which are often recurrent and difficult to manage. The aim of this master’s thesis was to develop and evaluate nanofibers for the incorporation of a model potentially probiotic strain Lactobacillus jensenii LJE6, in order to improve its stability and survival during preparation and storage.
In the initial phase, adhesion tests to mucin and growth experiments in different media formulations were performed, providing the basis for the subsequent development of nanofibers. Lactobacilli were incorporated into various nanofibers based on polyethylene oxide (PEO) and sodium alginate (ALG). Nanofibers were prepared by electrospinning, with process parameters such as flow rate and applied voltage being adjusted. The effects of antioxidant additives (glutathione and curcumin) as well as liposomes with or without curcumin on the electrospinning process, nanofiber morphology, and the viability of incorporated bacteria were investigated. Viability testing was used to evaluate the effects of formulation and storage conditions on the stability of the incorporated lactobacilli.
Cultivation of L. jensenii LJE6 in mucin-enriched De Man-Rogosa-Sharpe medium (MRS) significantly increased its adhesion to mucin compared with standard MRS medium (p < 0,001). A combination of PEO and ALG proved to be the most suitable polymeric matrix, as it had a favorable effect on bacterial growth. Incorporation of bacteria into liposomes did not affect their viability (p > 0,05), but it contributed to bacterial protection in subsequent stages of nanofiber production. The greatest decrease in bacterial viability was observed during the electrospinning process, with the smallest reduction observed in formulations containing liposomes. Prolongation of the electrospinning time resulted in a greater decline in bacterial viability in both the basic formulation (p < 0,05) and the liposome-containing formulation (p < 0,001). The latter also demonstrated improved preservation of bacterial viability during long-term storage, particularly under anaerobic conditions and at lower temperatures, whereas antioxidants did not contribute to enhanced survival of lactobacilli (p > 0,05). Based on these results, it can be concluded that the use of liposomes improves the protection of L. jensenii LJE6 during nanofiber fabrication and subsequent storage.
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