Primjena različitih mikrobioloških metoda za ispitivanje antibakterijske aktivnosti odabranih funkcionalnih starter kultura

undergraduate thesis

• Title (english): Application of various microbiological methods for testing the antimicrobial activity of selected functional starter cultures
• Author: Ana Pavić
• 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: 2013-06-13, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Biotechnology

Abstract

Tema ovoga rada je antimikrobno djelovanje funkcionalnih starter kultura Enterococcus faecium A7 i Lactobacillus fermentum A8, izoliranih iz hrvatskog tradicionalnog svježeg sira. Budući da je antagonističko djelovanje prema nepoželjnim i patogenim mikroroganizmima poželjno svojstvo starter kultura i probiotičkih sojeva, primjenom metode difuzije u agar je ispitano antibakterijsko djelovanje prema test-mikroorganizama: Escherichia coli 3014 i Salmonella enterica serovar Typhimurium FP1. Ispitana je i potencijalna bakteriocinska aktivnost autohtonih sojeva prema srodnim bakterijskim vrstama metodom s dvostrukim slojem agara. Bakterijski sojevi Ec. faecium A7 i Lb. fermentum A8 su inhibirali rast oba test-mikroorganizma te bakterija mliječne kiseline Lactobacillus rhamnosus GG, Enterococcus faecuim ATCC 9430 i Lactococcus lactis subsp. lactis LMG 9450. Turbidimetrijskom metodom je dodatno potvrđeno inhibicijsko djelovanje prema navedenim sojevima pri čemu je dokazano da je inhibicijski učinak supernatanata kultura toliko učinkovit da se može primijeniti i u razrijeđenom obliku, odnosno u matriksu gdje je potrebno antimikrobno djelovanje ispitivanog bakterijskog soja.

Abstract (english)

The subject of this work is antimicrobial activity of the functional starter cultures Enterococcus faecium A7 and Lactobacillus fermentum A8, isolated from Croatian traditional fresh cheese. Since the antagonistic activity against undesirable microorganisms and pathogens is desirable property of starter cultures and probiotic strains, antibacterial activity against testmicroorganisms Escherichia coli 3014 and Salmonella enterica serovar Typhimurium FP1 has been tested using agar diffusion method. Moreover, potential bacteriocinogenic activity of autochthonous strains against related bacterial species has been examined by agar-spot-test method. Bacterial strains Ec. faecium A7 and Lb. fermentum A8 inhibited the growth of both test-microorganisms and lactic acid bacteria Lactobacillus rhamnosus GG, Enterococcus faecium ATCC 9430 and Lactococcus lactis subsp. lactis LMG 9450. Inhibitory activity against these strains has been further confirmed by using turbidimetric method, wherein the inhibitory effect of cultures supernatants was so effective that it could be applied in diluted form, or in the matrix, where appropriate antimicrobial activity of tested bacterial strain is needed.

• Keywords: antimikrobna aktivnost; bakterije mliječne kiseline; probiotici; starter kulture
• Keywords (english): antimicrobial activity; bacteriocins; lactic acid bacteria; probiotics; starter cultures
• Language: croatian
• URN:NBN: urn:nbn:hr:159:447599
• 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: 2017-05-03 10:44:37