Impact of distillage recycling on the glycolysis key enzymes, stress response metabolites and intracelluler components of the self-flocculating yeast

• Published in: Shengwu gongcheng xuebao Vol. 26; no. 7; p. 1019
• Main Authors: Zi, Lihan, Zhang, Chunming, Ren, Jiangang, Yuan, Wenjie, Chen, Lijie
• Format: Journal Article
• Language: Chinese
• Published: China 01-07-2010
• Subjects: Bioreactors - microbiology; Ethanol - metabolism; Fermentation; Flocculation; Glycerol - metabolism; Glycolysis; Hexokinase - metabolism; Industrial Microbiology - methods; Phosphofructokinase-1 - metabolism; Saccharomyces cerevisiae - enzymology; Saccharomyces cerevisiae - genetics; Saccharomyces cerevisiae - metabolism; Schizosaccharomyces - enzymology; Schizosaccharomyces - genetics; Schizosaccharomyces - metabolism; Trehalose - metabolism; Triticum - metabolism; Zea mays - metabolism
• ISSN: 1000-3061

This research aimed to study the effect of distillage recycling on ethanol fermentation, the key glycolytic enzymes and cell composition of the self-flocculating yeast. With the self-flocculating yeast SPSC01 and medium composed of 220 g/L glucose, 8 g/L yeast extract and 6 g/L peptone, continuous ethanol fermentation was carried out at the dilution rate of 0.04 h(-1) with a 1.5 L tank bioreactor. Fermentation broth was collected every 3 days, and ethanol and other volatile byproducts were removed by distillation, but the stillage with high boiling byproducts was recycled to prepare the medium instead of fresh water. The system was run for 20 days, during which ethanol and biomass concentrations in the effluent decreased continuously, indicating the significant inhibition of the high boiling byproducts accumulated within the system. Thus, the activities of the key enzymes of the glycolytic pathway: hexokinase, 6-phosphofructose kinase, and pyruvate kinase were analyzed, and it was observed that all of them we