Antimikrobna aktivnost bakterija mliječne kiseline

master's thesis

• Title (english): Antimicrobial activity of lactic acid bacteria
• Author: Valentina Obadić
• Mentor: Andreja Leboš Pavunc (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: 2018-09-27, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Biotechnology

Abstract

Antimikrobna aktivnost bakterija mliječne kiseline predstavlja veliki značaj za prehrambenu industriju jer omogućava korištenje prirodnih konzervansa. Organske kiseline, diacetil, vodikov peroksid, reuterin i bakteriocini predstavljaju antimikrobne komponente metabolizma bakterija mliječne kiseline. Bakteriocini, koji su antimikrobni peptidi proizvedeni na ribosomima, imaju i primjenu u medicini kao tvari koje bi potencijalno mogle smanjiti uporabu antibiotika. U ovom radu ispitivana je antibakterijska aktivnost različitih sojeva, prisutnost bakteriocina te kompetitivna ekskluzija patogenih bakterija Listeria monocytogenes i Staphylococcus aureus s odabranim Lactobacillus plantarum sojevima. Najjače antimikrobno djelovanje prema patogenima L. monocytogenes i S. aureus dokazano je za sojeve L. plantarum D13, SF9C i SF15C kod kojih je i potvrđena prisutnost bakteriocina. Kompetitivna ekskluzija dokazala je da navedeni sojevi utječu na adheziju S. aureus dok na adheziju L. monocytogenes nemaju utjecaja.

Abstract (english)

Antimicrobal activity of lactic acid bacteria is of high importance for food industry because it enables use of natural preservatives. Organic acids, diacetly, hydrogen peroxide, reuterin and bacteriocines are antimicrobal components of lactic acid bacteria metabolism. Bacteriocines, which are ribosomally synthesised antimicrobic peptides, can also be used in medicine as substances which can reduce antibiotic consumption. In this thesis antimicrobal activity of lactic acid bacteria, presence of bacteriocines and competitive exclusion of Listera monocytogenes and Staphylococcus aureus with different Lactobacillus plantarum strains is researched. The strongest antimicrobal effect towards L. monocytognes and S. aureus is detected for L. plantarum D13, SF9C and SF15C strains in which also presence of bacteriocines is confirmed. Competitive exclusion proved that chosen strains affect adhesion of S. aureus while they have no affect on adhesion of L. monocytogenes.

• Keywords: bakterije mliječne kiseline; antimikrobna aktivnost; bakteriocini
• Keywords (english): lactic acid bacteria; antimicrobal activity; bacteriocines
• Language: croatian
• URN:NBN: urn:nbn:hr:159:483806
• Study programme: Title: Molecular Biotechnology; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka molekularne biotehnologije (magistar/magistra inženjer/inženjerka molekularne biotehnologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2019-11-27 11:23:15