Uloga egzopolisaharida u probiotičkoj aktivnosti soja producenta Lactobacillus fermentum D12

undergraduate thesis

• Title (english): The role of exopolysaccharide in probiotic activity from Lactobacillus fermentum D12 strain
• Author: Lorena Jaković
• Mentor: Jagoda Šušković (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Biochemical Engineering); (Laboratory for Antibiotic, Enzyme, Probiotic and Starter Cultures Technology); Zagreb
• Defense date and country: 2019-07-15, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Biotechnology

Abstract

Egzopolisaharidi, poznati kao mikrobni polisaharidi sintetizirani od strane određenih vrsta bakterija mliječne kiseline, pronašli su primjenu u raznim područjima zbog mnogih povoljnih učinaka. U ovom radu se istražilo kako koncentracija sintetiziranih mikrobnih biopolimera, soja producenta Lactobacillus fermentum D12, utječe na adhezijska svojstva i zaštitu stanica prilikom stresnih uvjeta. Usporedba preživjelih stanica prije i nakon liofilizacije te prolaska kroz simulirane uvjete gastrointestinalnog trakta, omogućila je donošenje zaključka o mogućoj probiotičkoj aktivnosti egzopolisaharida. Iako su rezultati liofilizacije pokazali veće preživljavanje uz prisustvo EPOL-a, razlike u rezultatima nisu bile značajne. Kod ispitivanja preživljavanja u uvjetima GIT-a vidljivo je veće preživljavanje stanica kod EPOL-a 0,2 mg/mL, ali ujedno i inhbicija rasta stanica kod EPOL-a 1 mg/mL. Na temelju izmjerene apsorbancije dobiveni su rezultati autoagregacije i adhezije na mucin za pojedine koncentracije egzopolisaharida te je vidljiv pozitivan učinak. Rezultati sposobnosti adhezije na Caco-2 stanice ukazuju da određena koncentracija EPOL-a omogućuje preživljavanje stanica.

Abstract (english)

Exopolysaccharides, known as microbial polysaccharides synthesized from specific types of lactic acid bacteria, are frequently used in variety of areas because of its favourable effects. This study explored how the concentration of synthesized microbial biopolymers of producer strain Lactobacillus fermentum D12, influences adhesive properties and cell protection during stressful conditions. Comparing surviving cells before and after lyophilization and going through simulated conditions of the gastrointestinal tract, enabled us to make conclusions about possible probiotic activity of exopolysaccharides. Although the results of lyophilization showed greater survival in the presence of EPOL, the difference in results was not significant. After survival studies in GIT conditions, better survival of cells was with 0.2 mg/mL EPOL, but also inhibition of cell growth with 1 mg/mL EPOL. Based on measured absorbency the results of autoaggregation and mucin-adhesion for different concentrations of exopolysaccharides had positive effect. The results of adherence to Caco-2 cells indicate that a certain concentration of EPOL allows cell survival.

• Keywords: bakterije mliječne kiseline; egzopolisaharidi; probiotička aktivnost
• Keywords (english): exopolysaccharides; lactic acid bacteria; probiotic activity
• Language: croatian
• URN:NBN: urn:nbn:hr:159:719891
• Study programme: Title: Biotechnology; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka biotehnologije (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka biotehnologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2019-07-29 06:58:00