Optimiziranje metode za brzo određivanje vijabilnosti kvasaca

undergraduate thesis

• Title (english): Optimization of method for fast assesment of yeast viability
• Author: Mia Radović
• Mentor: Anamarija Štafa (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Biochemical Engineering); (Laboratory for Biology and Microbial Genetics); Zagreb
• Defense date and country: 2017-09-08, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Biotechnology

Abstract

Alkoholna fermentacija proces je proizvodnje etanola iz fermentabilnih šećera, a najčešće ju provode kvasci iz roda Saccharomyces. Proces je potrebno kontinuirano nadzirati zbog pravovremenog otkrivanja potencijalne kontaminacije nepoželjnim mikroorganizmima. Jedan od važnih proizvodnih parametara je vijabilnost stanica kvasaca, no klasične mikrobiološke metode koje se koriste za analizu često su dugotrajne. Cilj ovog rada bio je optimizirati metodu za brzo određivanje postotka nevijabilnih stanica kvasaca, temeljenu na fluorescencijskoj mikroskopiji, pri čemu su korišteni kvasac Saccharomyces cerevisiae, koji provodi alkoholnu fermentaciju mošta, i kvasac Dekkera bruxellensis, najčešći kontaminant tijekom proizvodnje vina. Za usporednu analizu postotka nevijabilnih stanica u kulturi korištene su komercijalno dostupne fluorescentne boje: akridin oranž, floksin B, propidij jodid i tripan plavo, a rezultati su uspoređeni s postotkom nevijabilnih stanica određenim bojenjem metilenskim modrilom. Utvrđeno je da se bojanje tripan plavim ili propidij jodidom može koristiti za pouzdano određivanje postotka nevijabilnih stanica kvasaca S. cerevisiae i D. bruxellensis.

Abstract (english)

Alcohol fermentation is a process of ethanol production from fermentable sugars, usually done by yeasts from the Saccharomyces genus. It is necessary to continuously monitor fermentation process in order to detect different contaminant microorganisms. One of the most important parameters monitored is yeast viability, but the classical microbiological methods used for its determination require long time. The aim of this work was to optimise a method, based on a fluorescent microscopy, that will allow fast detection of the percentage of non viable yeasts in the culture. Several commercially available fluorescent dies were used: acridine orange, phloxin B, propidium iodide and tripan blue. The obtained results were compared with the percentage determined by staining with methylene blue. Both tripan blue and propidium iodide can be used for reliable determination of the percentage of non viable yeast cells of S. cerevisiae, the species responsible for alcohol fermentation, and Dekkera bruxellensis, the main contaminant during wine production.

• Keywords: fluorescencijska mikroskopija; Dekkera bruxellensis; Saccharomyces cerevisiae; vijabilnost
• Keywords (english): fluorescence microscopy; Dekkera bruxellensis; Saccharomyces cerevisiae; viability
• Language: croatian
• URN:NBN: urn:nbn:hr:159:614799
• 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: Open access
• Created on: 2017-09-11 09:57:38