Utjecaj temperature na rast i proizvodnju etanola kod kvasca Kluyveromyces marxianus NBRC 1777

undergraduate thesis

• Title (english): Influence of temperature on growth and production of yeast ethanol Kluyveromyces marxianus NBRC 1777
• Author: Monika Kralj
• Mentor: Mladen Pavlečić (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Biochemical Engineering); (Laboratory for Biochemical Engineering, Industrial Microbiology and Malting and Brewing Technology); Zagreb
• Defense date and country: 2020-09-15, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Biotechnology

Abstract

Kvasci se često koriste kao biokatalizatori u proizvodnji raznih fermentiranih proizvoda, kao i jakih alkoholnih pića te pekarskih proizvoda. Napretkom znanosti i različitih tehnika genetičkog inženjerstva, kvasci se počinju sve češće primjenjivati i u drugim biotehnološkim postupcima. Ne-Saccharomyces kvasci predstavljaju veliki no vrlo slabo iskorišten izvor bioraznolikosti ovih mikroorganizama. Za razliku od Saccharomyces kvasaca, oni pokazuju neke karakteristike koje ih čine interesantnima za istraživanje , poput mogućnosti rasta na kompleksnim supstratima, odnosno na supstratima koji su tvoreni od dva ili više biogenih elemenata, osim toga imaju i veću otpornost prema višim koncentracijama inhibitora ili visokim temperaturama. Jedan od interesantnijih ne- Saccharomyces kvasaca za istraživanje je i kvasac Kluyveromyces marxianus NRBC 1777. S obzirom da spada u termotolerantne kvasce, neka istraživanja pokazala su da može rasti i pri temperaturama od 52°C, dok se s druge strane pokazalo da je i dobar producent etanola na temperaturama od čak 40°C. U ovom završnom radu proučavan je uzgoja kvasca K. marxianus NBRC 1777 u anaerobnim uvjetima u tikvici pri temperaturama od 20°, 30°, 40° i 50°C. Tokom ovog istraživanja kvasca određivana je specifična brzina rasta kvasca pri tim temperaturama, kao i mogućnost proizvodnje etanola. Najveća specifična brzina rasta određena je pri 30° C i 40°C, također, kvasac je pokazao mogućnost proizvodnje etanola pri svim temperaturama, a prinos etanola je bio najviši pri 30°C. Najlošiji rezultati ostvarili su se na temperaturma od 20°C i 50°C.

Abstract (english)

Yeasts are often used as biocatalysts in the production of various fermented products, as well as strong alcoholic beverages and bakery products. With the advancement of science and various techniques of genetic engineering, yeasts are beginning to be used more and more often in other biotechnological processes. Non-Saccharomyces yeasts represent a large but very underused source of biodiversity of these microorganisms. Unlike Saccharomyces yeasts, they show some characteristics that make them interesting for research, such as the possibility of growth on complex substrates, ie on substrates formed of two or more biogenic elements, in addition, they have greater resistance to higher concentrations of inhibitors or high temperatures. One of the more interesting non-Saccharomyces yeasts for research is the yeast Kluyveromyces marxianus NRBC 1777. Since it belongs to the thermotolerant yeasts, some research has shown that it can grow at temperatures of 52° C, while on the other hand it has been shown to be good. Ethanol producer at temperatures as high as 40 ° C. In this final work, the cultivation of yeast K. marxianus NBRC 1777 under anaerobic conditions in a flask at temperatures of 20°, 30°, 40° and 50° C was studied. During this study of yeast, the specific growth rate of yeast at these temperatures was determined, as well as the possibility of ethanol production. The highest specific growth rate was determined at 30°C and 40°C, also, yeast showed the possibility of ethanol production at all temperatures, and the ethanol yield was highest at 30°C. The worst results were achieved at temperatures of 20°C and 50°C.

• Keywords: ne-Saccharomyces kvasci; Kluyveromyces marxianus NRBC 1777; termotolerantnost; etanol
• Keywords (english): non-Saccharomyces yeasts; Kluyveromyces marxianus NBRC 1777; different temperatures; ethanol
• Language: croatian
• URN:NBN: urn:nbn:hr:159:080412
• 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: 2020-10-22 13:28:57