Short communication, Note
https://doi.org/10.17113/ftb.53.01.15.3617
Effect of Ethanol Stress on Fermentation Performance of Saccharomyces cerevisiae Cells Immobilized on Nypa fruticans Leaf Sheath Pieces
Hoang Phong Nguyen
; Department of Food Technology, Ho Chi Minh City University of Technology, Ho Chi Minh City, Vietnam
Hoang Du Le
; Department of Food Technology, Ho Chi Minh City University of Technology, Ho Chi Minh City, Vietnam
Van Viet Man Le
orcid.org/0000-0003-3284-207X
; Department of Food Technology, Ho Chi Minh City University of Technology, Ho Chi Minh City, Vietnam
Abstract
The yeast cells of Saccharomyces cerevisiae immobilized on Nypa fruticans leaf sheath pieces were tested for ethanol tolerance (0, 23.7, 47.4, 71.0 and 94.7 g/L). Increase in the initial ethanol concentration from 23.7 to 94.7 g/L decreased the average growth rate and concentration of ethanol produced by the immobilized yeast by 5.2 and 4.1 times, respectively. However, in the medium with initial ethanol concentration of 94.7 g/L, the average growth rate, glucose uptake rate and ethanol formation rate of the immobilized yeast were 3.7, 2.5 and 3.5 times, respectively, higher than those of the free yeast. The ethanol stress inhibited ethanol formation by Saccharomyces cerevisiae cells and the yeast responded to the stress by changing the fatty acid composition of cellular membrane. The adsorption of yeast cells on Nypa fruticans leaf sheath pieces of the growth medium increased the saturated fatty acid (C16:0 and C18:0) mass fraction in the cellular membrane and that improved alcoholic fermentation performance of the immobilized yeast.
Keywords
Saccharomyces cerevisiae; immobilized yeast; ethanol stress; Nypa fruticans; fatty acids
Hrčak ID:
136930
URI
Publication date:
30.3.2015.
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