University of Natural Resources and Life Sciences, Vienna (BOKU) - Research portal
Gewählte Master / Diploma Thesis:
Carina Frischauf
(2015):
Comparison of the impact of natural antimicrobials on probiotics and pathogens.
Master / Diploma Thesis - Institut für Lebensmittelwissenschaften,
BOKU-Universität für Bodenkultur,
pp 113.
UB BOKU
obvsg
- Abstract:
- Natural antimicrobials have been more and more in the focus of interest in the last years. In times where antibiotic resistance poses a dangerous problem, it is important to look for other relevant substances and alternatives. The aim of this study was to find a substance which increases the growth and adhesion of probiotics and acts in an antimicrobial and anti-adhesive way against pathogens. Thus, antimicrobial tests on planktonic cells and adhesion tests were performed investigating probiotic as well as pathogenic strains. Firstly minimal inhibitory concentrations (MIC) values were determined for Campylobacter, Listeria and Lactobacillus. Subsequently the biofilm formation was tested, and as a consequence of this, the influence of the substances on Campylobacter and Lactobacillus during biofilm formation was checked. The substances tested were the following plant extracts: Semen paradisi and Semen paradisi after distillation, Juniper fructus, essential oil from Juniper fructus, Juniper fructus after distillation, Calluna vulgaris (= Ericae flos), Folium plantaginis, Glandula lupuli, Alpinia katsumadai, and Alpinia katsumadai after distillation. Also five further substances were used (M1, M2, M3, M4, M5). Those substances were generally pure substances. M1 was arabinogalactan, M3 dihydroquercitin, and M4 was royal jelly. M2 and M5 were also arabinogalactan samples. Listeria strains were not very sensitive against the investigated substances. Semen paradisi was the most active plant extract against Campylobacter strain NCTC 11168. This substance also inhibited the growth of Lactobacillus next to Juniper fructus. M1 and M4 seemed to be interesting because both could inhibit the growth of the tested Campylobacter strains at higher concentrations, whereas they were not active against Lactobacillus. Furthermore M4 was also anti-adhesive against Campylobacter strain NCTC 11168.
- Beurteilende(r): Kneifel Wolfgang
- 1.Mitwirkender: Mayrhofer Sigrid
- 2.Mitwirkender: Domig Konrad