Prethodno priopćenje
Zinc, Copper and Manganese Enrichment in Yeast Saccharomyces cerevisae
Vesna Stehlik-Tomas
; Laboratory of Fermentation and Yeast Technology, Faculty of Food Technology and Biotechnology, University of Zagreb, Pierottijeva 6, HR-10000 Zagreb, Croatia
Vlatka Gulan Zetić
; Laboratory of Fermentation and Yeast Technology, Faculty of Food Technology and Biotechnology, University of Zagreb, Pierottijeva 6, HR-10000 Zagreb, Croatia
Damir Stanzer
; Laboratory of Fermentation and Yeast Technology, Faculty of Food Technology and Biotechnology, University of Zagreb, Pierottijeva 6, HR-10000 Zagreb, Croatia
Slobodan Grba
; Laboratory of Fermentation and Yeast Technology, Faculty of Food Technology and Biotechnology, University of Zagreb, Pierottijeva 6, HR-10000 Zagreb, Croatia
Nada Vahčić
; Laboratory of Fermentation and Yeast Technology, Faculty of Food Technology and Biotechnology, University of Zagreb, Pierottijeva 6, HR-10000 Zagreb, Croatia
Sažetak
The aim of the present work was to study the incorporation of some microelements in the yeast Saccharomyces cerevisiae and its impact on the physiological state of the yeast cells during the alcoholic fermentation. The cultivations were performed on molasses medium in anaerobic (thermostat) and semiaerobic (shaker) conditions, with and without the addition of zinc, copper and manganese sulphate (0.1 g/L of each) at 30 °C and different pH values of the medium (3.5–6.0) for 8 h. The addition of the mentioned salts in molasses medium enhanced the yield of the yeast biomass up to 30 % in semiaerobic conditions, but the ethanol yield was changed very little. On the other hand, in anaerobic conditions the yields of the yeast biomass were increased up to 10 % and alcohol yield up to 20 %. After the fermentations were performed, the concentration of metal ions in yeast cells was determined. Different values were achieved depending on the used growth conditions. The highest amount of Zn ions in dry matter (700 μg/g) was incorporated in the yeast biomass under anaerobic conditions. In contrast, the incorporation of Cu and Mn was preferred in semiaerobic conditions and the highest value of Cu2+ ions in dry matter (1100 μg/g) and Mn2+ in dry matter (300 μg/g) in yeast biomass were obtained. Optimal pH for all ion incorporations was between 4 and 5.
Ključne riječi
yeast enriched with microelements; Saccharomyces cerevisiae; alcoholic fermentation; zinc; copper; manganese
Hrčak ID:
110811
URI
Datum izdavanja:
15.6.2004.
Posjeta: 5.126 *