Postupci izolacije β-glukana iz pivskog kvasca

master's thesis

• Title (english): Isolation methods of β-glucan from brewer's yeast
• Author: Ksenija Veček
• Mentor: Vesna Zechner-Krpan (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: 2004-10-04, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Biotechnology

Abstract

ß-glukan je široko rasprostranjen polisaharid u mikroorganizmima, gljivama i biljkama. Već prije 50 godina opisani su njegovi doprinosi zdravlju ljudi i životinja, a danas je klasificirani modifikator biološkog odgovora. Jedan od lako dostupnih izvora ß-1,3-glukana je i stanična stijenka pivskog kvasca, Saccharomyces cerevisiae. Otpadni pivski kvasac Saccharomyces cerevisiae, prvo je odgorčen lužinom (5 minuta pri 60 ºC), a potom autoliziran kroz 36 sati pri 50 ºC. Slijedile su izolacije ß-glukana alkalnom te alkalno-kiselinskom ekstrakcijom. U oba postupka izolacija s lužinom trajala je 2 sata na 90 ºC. Kod alkalno-kiselinske ekstrakcije nakon lužine djelovano je kiselinom (2 sata na 20ºC). Nakon ispiranja vodom i sušenja dobiveni preparat ß-glukana pokazao je sposobnost geliranja, pa se može koristiti kao uguščivač u prehrambenoj industriji. Nakon ispiranja etanolom i sušenja, alkalnom ekstrakcijom dobiven je prah smeđe boje, a alkalno-kiselinskom prah boje bijele kave. Oba praha se mogu primijeniti kao dodaci stočnoj hrani ili preparatima za životinje.

Abstract (english)

β-glucan, a polysaccharide found in many microorganisms, mushrooms and plants has a numerous health benefits on humans and animals known for more then 50 years. Today β-glucans are classified as biological response modifiers. The cell wall of the common brewer's yeast Saccharomyces cerevisiae, is one of the most easily available sources of β-1,3-glucan. Spent brewer's yeast Saccharomyces cerevisiae was at first debittered by alkali (5 min/60 ºC) and then autolyzed during 36 hours at 50 ºC. After that followed alkali and alkali-acid extraction. The alkali treatment (2 hrs/90 ºC) was applied in both extraction procedures. In the alkali-acid extraction after alkali treatment acid was applied for 2 hrs/20 ºC. Isolated β-glucan, after washing and air-drying, showed the ability of gelling. After alkali extraction, washing with ethanol and air-drying obtained powder was brown and after alkali-acid treatment white-coffee colour. Both powders could be used as natural safe supplements or feed adittives.

• Keywords: β-glukan; pivski kvasac; Saccharomyces cerevisiae
• Keywords (english): β-glucan; brewer's yeast; Saccharomyces cerevisiae
• Language: croatian
• URN:NBN: urn:nbn:hr:159:490323
• Study programme: Title: Biotechnology; specializations in: Biochemical Engineering; Course: Biochemical Engineering; Study programme type: university; Study level: graduate; Academic / professional title: diplomirani inženjer biotehnologije; smjer biokemijsko inženjerstvo (diplomirani inženjer biotehnologije; smjer biokemijsko inženjerstvo)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2017-09-12 10:02:36