Le Nhu Ngoc Ta, Thi Hong Chau Nguyen and Van Viet Man Le

DOI: 10.14456/sjst-psu.2016.45

pp. 333 - 341

Abstract

Water hyacinth (Eichhorniacrassipe) stem pieces were used as supports for Saccharomyces cerevisiae immobilization. The response surface methodology was implemented to maximize the cell immobilization yield. This methodology
optimized the amount of water hyancinth pieces added to yeast suspension and the initial cell concentration in yeast suspension prior to the immobilization. The immobilized yeast on water hyacinth stem pieces was then applied to ethanol fermentation with 12 repeated batches. The ethanol production rate of the immobilized yeast was significantly higher than that of the
free yeast. In addition, gradual increase in the metabolic activity of the immobilized cell system was also observed during
the 12 fermentation batches. The ethanol production rate of the immobilized yeast in the twelfth batch culture was increased
by 29.8% compared to that in the first batch culture.

Keywords

• ethanol
• fermentation
• immobilization
• Saccharomyces cerevisae
• water hyacinth