Farklı Yöntemler ile Enkapsüle Edilen Probiyotiklerin İn Vitro ve İn Vivo Etkinliğinin Belirlenmesi
Özet
Probiotics have beneficial effects on several diseases although, very few studies evaluate their effects in healthy individuals. This study aimed to evaluate the viability levels of different probiotic species by encapsulation (EK) with different methods, compare the methods in vitro, determine their stability under short-term storage conditions, and examine the effects of probiotics on inflammation biomarkers in healthy mice in vivo. Lactobacillus Rhamnosus (LGG) and Escherichia coli Nissle 1917 (EcN), which were known effective in inflammation, were encapsulated using microencapsulation (ME) and nanoencapsulation (NE) methods in the study. The method that preserves the higher viability of probiotics in vitro conditions was chosen, and their stability in storage conditions (+4°C) for one week was evaluated. In vivo assay was performed on the healthy C57BL/ 6J male mice (n=35). Microencapsulated probiotics and phosphate-buffered saline (PBS) were given to mice daily for six weeks by oral gavage. At the end of the probiotics intervention, inflammatory cytokine (IL-4, IL-6, IL-10, TNF- α ve IFN-γ) gene expression levels were analyzed from the liver tissues. As a result, free bacteria lost their viability significantly in vitro conditions (p<0.05), while the viability of probiotics were higher in bacteria encapsulated by both methods (p<0.05 for EcN and p>0.05 for LGG). When the encapsulation methods were compared in terms of viability, it was found that viability of LGG preserved similarly in both methods (for microencapsulation, 41.9±1.24% and nanofiber encapsulation, 41.2±7.05%). In contrast, the viability of EcN was higher in the microencapsulation method than encapsulation with nanofiber (83.9%±1.31% and 71.2%±1.65%, respectively, p<0.05). There was no significant decrease in their viability after the first, third and seventh days of storage (+4°C) (p>0.05). IFN-γ levels were significantly different between free EcN, ME EcN and control groups (p=0.048). There was no significant difference between the groups in IL-6, TNF-α, IL-4 and IL-10 levels (p>0.05). This study results indicate that the encapsulated forms of probiotics preserve the viability of probiotics greater, increase their stability than the free forms, and have no effect on inflammation in healthy mice. The results of this study are thought to guide the studies related to nanofiber encapsulation using different materials and to evaluate the effectiveness of the encapsulated probiotics in healthy individuals.