Ethanol fermentation is the metabolic conversion of organic substrates into ethanol through reactions coupled to cellular energy generation and redox balance. In yeast, sugar catabolism supplies pyruvate, which is converted through acetaldehyde to ethanol [1]. Reduction of acetaldehyde reoxidizes NADH to NAD+, sustaining continued glycolytic turnover and its associated substrate-level phosphorylation [2]. The sugars entering this process must be accessible to the organism's uptake and metabolic pathways; complex polysaccharides require prior hydrolysis, and pentose utilization requires the appropriate enzymatic routes [3]. Fermentative carbon flow can coexist with respiratory metabolism, and high glycolytic flux can promote ethanol formation in Crabtree-positive yeasts. The process therefore links carbon conversion, nucleotide-cofactor recycling, and allocation of substrate between growth and fermentation products [4][5].
- ethanol
- alcohol dehydrogenase
- glycolysis
- NAD+ regeneration
References
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