Utjecaj S-proteina na potencijalna probiotička svojstva bakterija mliječne kiseline izoliranih iz majčinog mlijeka

master's thesis

• Title (english): The influence of S-layer proteins on potential probiotic properties of lactic acid bacteria isolated from breast milk
• Author: Andrea Zrinjan
• Mentor: Andreja Leboš Pavunc (mentor)
• Committee member: Jagoda Šušković (član povjerenstva)
• 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: 2021-09-20, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Cilj ovog rada bio je ispitati utjecaj S-proteina, koje eksprimiraju 4 Lactobacillus brevis soja (MB1, MB2, MB13 i MB20) izolirana iz majčinog mlijeka, na njihova potencijalna probiotička svojstva. Kompetitivna ekskluzija bakterije E. coli 3014 s navedenim sojevima ispitana je in vitro primjenom Caco-2 stanične linije, a svojstvo koagregacije s patogenim bakterijama Listeria monocytogenes ATCC 19111, Staphylococcus aureus 3048, Salmonella enterica serovar Typhimurium FP1 i E. coli 3014. Nakon uklanjanja S-proteina sa stanične površine ispitivanih sojeva BMK smanjena je uspješnost kompetitivne ekskluzije patogene bakterije, kao i sposobnost autoagregacije i koagregacije s ispitivanim patogenim bakterijama. Osim navedenog, uklanjanje S-proteina utjecalo je na smanjenu sposobnost preživljavanja Lactobacillus sojeva u simuliranim uvjetima želučanog soka i soka tankog crijeva.

Abstract (english)

The aim of this study was to examine the influence of S-layer proteins from 4 Lactobacillus brevis strains (MB1, MB2, MB13 and MB20) isolated from breast milk on their potential probiotic properties. The competitive exclusion of E. coli 3014 with Lactobacillus strains was examined in vitro on Caco-2 cell line. The coaggregation ability was examined using pathogens Listeria monocytogenes ATCC 19111, Staphylococcus aureus 3048, Salmonella enterica serovar Typhimurium FP1 and E. coli 3014. The competitive exclusion activity of LAB strains was significantly decreased after the removal of S-layer proteins from their cell surface, as well as the autoaggregation and the coaggregation ability with the examined pathogenic bacteria. Also, the removal of S-layer proteins from Lactobacillus strains reduced their viability in simulated gastric and small intestinal juices.

• Keywords: majčino mlijeko; bakterije mliječne kiseline; probiotici; S-proteini
• Keywords (english): breast milk; lactic acid bacteria; probiotics; S-layer proteins
• Language: croatian
• URN:NBN: urn:nbn:hr:159:548720
• Study programme: Title: Food Safety Management; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka upravljanja sigurnošću hrane (magistar/magistra inženjer/inženjerka upravljanja sigurnošću hrane)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2021-10-04 10:24:56