Optimalizacija autolize pekarskog kvasca Saccharomyces cerevisiae za proizvodnju okusnih 5'-ribonukleotida

master's thesis

• Title (english): Autolysis optimization of baker’s yeast Saccharomyces cerevisiae autolysis for 5’-ribonucleotides production
• Author: Iris Grubić
• Mentor: Sunčica Beluhan (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: 2005-12-13, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Biotechnology

Abstract

Okusni 5'- ribonukleotidi (5'-IMP i 5'-GMP) koriste se u prehrambenoj industriji, uz natrijev glutaminat (MSG), kao okusne supstancije koje obogaćuju okus hrane. Za dobivanje 5'- ribonukleotida u ovom radu je autoliziran kvasac Saccharomyces cerevisiae i proučavani su uvjeti optimalizacije autolize. Autoliza je trajala 10 sati (uz konstantno miješanje pomoću mehaničke mješalice) u rasponu pH vrijednosti od 5,0 do 9,0 i pri temperaturama od 50 do 70 oC. Najbolji uzorci bili su pri pH 8,5, na temperaturi od 60 °C (odnos A260/A280 iznosio je 1,9482). Broj mrtvih stanica nakon autolize iznosio je 93 %. Uzorcima su zatim dodani komercijalni pripravci enzima 5'-fosfodiesteraze i adenilat deaminaze, te im je na HPLC-u određen sastav i koncentracija 5'-ribonukleotida u autolizatu.

Abstract (english)

5’-ribonucleotides (5'-IMP and 5'-GMP) and monosodium glutamate, are well known flavor enhancers. Bakers yeast, Saccharomyces cerevisiae, is widely available source of 5'-ribonucleotides. Autolysis was used for production of bakers yeast cream and 5'-ribonucleotides. One of the aims of this work was to develop an optimal strategy for conducting autolysis and to study the composition of autolysates. Autolysis was conducted for 10 hours (with constant mechanical stirring) at pH range 5.0-9.0, and temperature range from 50 °C to 70 °C. Best sample were at pH 8,5, temperature 60 °C (A260/A280=1,9482). The composition and concentration of 5’-ribonucleotides was determined with HPLC, after adding enzymes 5’-phosphodiesterase and adenylic deaminase.

• Keywords: autoliza; pekarski kvasac; Saccharomyces cerevisiae; 5'-ribonukleotidi; HPLC
• Keywords (english): autolysis; baker’s yeast; Saccharomyces cerevisiae; 5’-ribonucleotides; HPLC
• Language: croatian
• URN:NBN: urn:nbn:hr:159:894909
• 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: 2017-09-11 13:46:53