Transport and intracellular accumulation of acetaldehyde in Saccharomyces cerevisiae

Journal Article · Sat Jun 05 04:00:00 EDT 1993 · Biotechnology and Bioengineering; (United States)

DOI:https://doi.org/10.1002/bit.260420104· OSTI ID:6759449

Stanley, G A; Pamment, N B ^[1]

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1. Univ. of Melbourne, Victoria (Australia)

The rate of acetaldehyde efflux from yeast cells and its intracellular concentration were studied in the light of recent suggestions that acetaldehyde inhibition may be an important factor in yeast ethanol fermentations. When the medium surrounding cells containing ethanol and acetaldehyde was suddenly diluted, the rate of efflux of acetaldehyde was slow relative to the rate of ethanol efflux, suggesting that acetaldehyde, unlike ethanol, may accumulate intracellularly. Intracellular acetaldehyde concentrations were measured during high cell density fermentations, using direct injection gas chromatography to avoid the need to concentrate or disrupt the cells. Intracellular acetaldehyde concentrations substantially exceeded the extracellular concentrations throughout fermentation and were generally much higher than the acetaldehyde concentrations normally recorded in the culture broth in ethanol fermentations. The technique used was sensitive to the time taken to cool and freeze the samples. Measured intracellular acetaldehyde concentrations fell rapidly as the time taken to freeze the suspensions was extended beyond 2 s. The results add weight to recent claims that acetaldehyde toxicity is responsible for some of the effects previously ascribed to ethanol in alcohol fermentations, especially Zymomonas fermentations. Further work is required to confirm the importance of acetaldehyde toxicity under other culture conditions.

• OSTI ID: 6759449
• Journal Information: Biotechnology and Bioengineering; (United States), Journal Name: Biotechnology and Bioengineering; (United States) Vol. 42:1; ISSN BIBIAU; ISSN 0006-3592
• Country of Publication: United States
• Language: English

Related Subjects

09 BIOMASS FUELS
090900* -- Biomass Fuels-- Processing-- (1990-)
560300 -- Chemicals Metabolism & Toxicology
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ACETALDEHYDE
ALCOHOLS
ALDEHYDES
BIOCONVERSION
BIOLOGICAL ACCUMULATION
BIOSYNTHESIS
CHROMATOGRAPHY
ETHANOL
EUMYCOTA
FERMENTATION
FUNGI
GAS CHROMATOGRAPHY
GROWTH
HYDROXY COMPOUNDS
MEMBRANE TRANSPORT
MICROORGANISMS
ORGANIC COMPOUNDS
PLANTS
SACCHAROMYCES
SACCHAROMYCES CEREVISIAE
SEPARATION PROCESSES
SYNTHESIS
TOXICITY
YEASTS