Ergosterol synthesis and population analysis of a fed-batch fermentation in Saccharomyces cerevisiae

• Published in: Folia microbiologica Vol. 30; no. 2; p. 134
• Main Authors: Pichová, A, Beran, K, Bĕhalová, B, Zajícek, J
• Format: Journal Article
• Language: English
• Published: United States 01.01.1985
• Subjects: Ergosterol - biosynthesis; Fermentation; Kinetics; Saccharomyces cerevisiae - growth & development; Saccharomyces cerevisiae - metabolism; Time Factors
• ISSN: 0015-5632
• DOI: 10.1007/BF02922206

Saccharomyces cerevisiae with an increased content of ergosterol or delta 5,7-sterols, growing on a molasses medium with a feed of ethanol and (NH4)2HPO4, was analyzed as to the age of cell population. The analysis was done by centrifugation in a dextran gradient and by a fluorescence-microscopic technique. In the phase of batch fermentation at a mean specific growth rate of 0.22 h-1 daughter cells contained less than 1% ergosterol while the ergosterol content of mother cells depended on the time of cultivation, a maximum level (4%) being found after two generation times. In the fed-batch phase at a mean growth rate of 0.052 h-1, both daughter and mother cells contained about the same amount of ergosterol (4.7-5.5%). Differences between daughter and mother cells are discussed in view of the relationship between the growth rate and the growth cycle.