Razvoj polimernih nanovlaken z laktobacili za izboljšanje preživetja bakterij med vgrajevanjem in shranjevanjem

Bizalj, Neža (avtor), Zupančič, Špela (mentor), Grilc, Nina Katarina (komentor)

Neravnovesje v sestavi vaginalne mikrobiote lahko vodi v različne okužbe, ki lahko povzročajo nelagodje in resnejše zdravstvene zaplete. Uporaba probiotikov, zlasti sevov rodu Lactobacillus, ki prevladujejo v mikrobioti zdrave sluznice, se je izkazala kot uspešna strategija za obnovo in vzdrževanje ravnovesja v vaginalni mikrobioti. Elektrostatsko sukanje za vgradnjo laktobacilov v nanovlakna je obetaven pristop, saj omogoča, da v enem koraku bakterije stabiliziramo s sušenjem in jih vgradimo v polimerni dostavni sistem z izbranimi lastnostmi. Cilj naloge je bil razviti formulacijo polimernih nanovlaken z bakterijskim sevom vrste Lactobacillus jensenii, ki bi izboljšala preživetje bakterij med elektrostatskim sukanjem in shranjevanjem. Najprej smo v preliminarnih poskusih izbrali ustrezen bakterijski sev vrste L. jensenii in optimizirali postopke njegovega gojenja ter priprave polimerno-bakterijskih disperzij za elektrostatsko sukanje. Optimizacija je obsegala izbor ustreznega volumna tekočega gojišča, pogojev ter časa gojenja in izbor ustreznih disperznih medijev za spiranje ter redispergiranje bakterijskih suspenzij. Bakterijski sev L. jensenii ATCC 25258 je kljub optimizaciji procesov gojenja in priprave disperzije izkazal visoko občutljivost na različne korake v vgradnji v nanovlakna, zato smo izbrali drug sev L. jensenii LJE6 z boljšo stabilnostjo, ki je preživel vgradnjo v polimerna nanovlakna. Za preučevanje formulacij za izboljšanje preživetja laktobacilov pri vgradnji in shranjevanju v nanovlaknih smo L. jensenii LJE6 vgradili v liposome z ali brez antioksidanta kurkumina. Sama vgradnja v liposome ni vplivala na njihovo živost. Nato smo pripravili tri formulacije polimernih nanovlaken: z L. jensenii LJE6, L. jensenii LJE6 vgrajenimi v liposome in z L. jensenii LJE6 vgrajenimi v liposome skupaj s kurkuminom. Pri vseh formulacijah je elektrostatsko sukanje potekalo stabilno, omogočilo tvorbo gladkih nanovlaken in uspešno vgradnjo bakterij z ohranjanjem delnega preživetja. Liposomi brez kurkumina niso imeli zaščitnega učinka na bakterije med elektrostatskim sukanjem, medtem ko so liposomi s kurkuminom statistično značilno izboljšali preživetje bakterij med procesom (p < 0.05). Kljub temu pa liposomi niti z niti brez kurkumina niso izboljšali bakterijskega preživetja pri shranjevanju nanovlaken na -20 °C 14 dni (p > 0.05).

• Jezik: Slovenski jezik
• Ključne besede: nanovlakna, elektrostatsko sukanje, probiotiki, liposomi, kurkumin
• Vrsta gradiva: Magistrsko delo/naloga
• Organizacija: FFA - Fakulteta za farmacijo
• Leto izida: 2025
• PID: 20.500.12556/RUL-168773
• Datum objave v RUL: 24.04.2025

Sekundarni jezik

• Jezik: Angleški jezik
• Naslov: Development of polymeric nanofibers with lactobacilli for enhancing bacterial survival during incorporation and storage

Izvleček

An imbalance in the composition of vaginal microbiota can lead to various infections, which may cause discomfort and more serious health complications. The use of probiotics, particularly strains of the Lactobacillus genus, which dominate the microbiota of healthy mucosa, has proven to be an effective strategy for restoring and maintaining a healthy vaginal microbiota. Electrospinning represents a promising technique for incorporating lactobacilli into nanofibers, as it enables simultaneous bacterial stabilization through drying and their encapsulation in a polymer-based delivery system with specific functional properties. The aim of this study was to develop a formulation of polymeric nanofibers containing a bacterial strain of Lactobacillus jensenii that would enhance bacterial survival during electrospinning and storage. A suitable L. jensenii strain was selected based on preliminary experiments, followed by optimization of its cultivation and the preparation of polymer-bacteria dispersions for electrospinning. The optimization included the selection of the appropriate volume of liquid culture medium, conditions and duration of cultivation and the choice of suitable dispersion media for washing and redispersing bacterial suspensions. Despite the optimization of the cultivation and dispersion preparation processes, the L. jensenii ATCC 25258 strain exhibited high sensitivity in various steps of incorporation into polymeric nanofibers. Therefore, a more stable strain, L. jensenii LJE6, demonstrating greater stability and survival during incorporation, was selected. For improving lactobacilli survival during incorporation and storage, L. jensenii LJE6 was encapsulated in liposomes with or without the antioxidant curcumin. Liposomal encapsulation alone did not affect bacterial viability. Three formulations of polymeric nanofibers were then prepared: with L. jensenii LJE6 alone, L. jensenii LJE6 encapsulated in liposomes, and L. jensenii LJE6 encapsulated in liposomes with curcumin. All formulations enabled a stable electrospinning process, resulting in smooth nanofibers and successful bacterial incorporation with partial viability retention. Liposomes without curcumin did not protect bacteria during electrospinning, whereas curcumin-loaded liposomes significantly enhanced bacterial survival throughout the process (p < 0,05). However, liposomes, regardless of curcumin content, did not enhance bacterial survival during storage of the nanofibers at −20 °C for 14 days (p > 0,05).

• Ključne besede: nanofibers, electrospinning, probiotics, liposomes, curcumin