Antimikrobna aktivnost bakterija mliječne kiseline na rast bakterije Escherichia coli

master's thesis

• Title (english): Antimicrobial activity of Lactic acid bacteria on the growth of bacteria Escherichia coli
• Author: Maja Žanko
• Mentor: Frane Delaš (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Biochemical Engineering); (Laboratory for General Microbiology and Food Microbiology); Zagreb
• Defense date and country: 2009-06-02, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Biotechnology

Abstract

Posljednjih tridesetak godina istražuje se mogućnost primjene bakterija mliječne kiseline (BMK) kao probiotičkih pripravaka, u terapijske svrhe, a u svrhu poboljšanja ljudskog zdravlja na prirodan način. Jedno od najznačajnijih djelovanja BMK je antimikrobno djelovanje prema patogenim mikroorganizmima. Stoga je u ovom diplomskom radu istražena mogućnost antimikrobne aktivnosti BMK na rast Escherichia coli, bakterije koja čini sastavni dio probavnog sustava čovjeka te je potencijalni patogen koji može uzrokovati veliki broj bolesti. Provedena su istraživanja krivulje rasta Escherichia coli pri odabranim temperaturama uzgoja (37°C i 45°C). Istraživanja su pokazala povoljnije uvjete rasta istraživanog mikroorganizma pri 37°C. Također su istraženi uvjeti rasta bakterije E. coli u prisutnosti supernatanta BMK Lactobacillus acidophilus M92 i Lactobacillus plantarum L4 pri odabranim temperaturama uzgoja od 37°C i 45°C u vremenskom periodu od 72 sata. Istraživanja su pokazala da oba supernatanta pri odabranim temperaturama imaju inhibitoran učinak, s time da je snažniji onaj supernatanta BMK L.acidophilus M92.

Abstract (english)

For the past thirty years, many researches have been conducted with the aim of using Lactic acid bacteria (LAB) as probiotics, in order to enhance man's health with its possible terapeutic effect. One of the best effects of such bacteria is its antimicrobial activity against pathogenic microorganisms. Therefore, this work investigates the possibility of such antimicrobial activity against the growth of Escherichia coli, a bacteria that lives in the human digestive system and is potentially pathogen. Experiments have been carried out in order to trace growth curves of Escherichia coli at elevated temperatures (37 °C and 45 °C). The experiments proved that better conditions for the bacteria's growth were at 37 °C. Other experiments investigated the growth of E. coli in presence of LAB supernatant (Lactobacillus acidophilus M92 and Lactobacillus plantarum L4) at the temperature of 37 °C and 45 °C through a period of time of 72 hours. The results of such experiments show that, at those temperatures, both supernatants have an inhibitory effect, which is stronger in the case of supernatant LAB L. acidophilus M92.

• Keywords: disk-difuzijska metoda; Escherichia coli; inhibicija rasta; Lactobacillus acidophilus M92; Lactobacillus plantarum L4.
• Keywords (english): disk-diffusion method; Escherichia coli; inhibition of growth; Lactobacillus acidophilus M92; Lactobacillus plantarum L4
• Language: croatian
• URN:NBN: urn:nbn:hr:159:805619
• Study programme: Title: Food Technology; specializations in: Nutrition; Course: Nutrition; Study programme type: university; Study level: graduate; Academic / professional title: diplomirani inženjer prehrambene tehnologije; smjer nutricionizam (diplomirani inženjer prehrambene tehnologije; smjer nutricionizam)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2017-08-31 07:46:46