Comparative physiology of Kluyveromyces marxianus and Saccharomyces cerevisiae during batch cultivation on glucose as a sole carbon source

Abstract

The consumption of substrate glucose, biomass formation, growth pattern of Kluyveromyces marxianus MTCC 4139 and Saccharomyces cerevisiae MTCC 173 was measured in batch level bioreactor cultivation, using minimal and synthetic media containing glucose as the main carbon source. A comparative maximum specific growth rate on glucose (50 g/L) by K. marxianus at 37°C and S. cerevisiae at 30°C was found to be 0.35± 0.011 and 0.38 ± 0.009 h^-1  respectively in synthetic media. Increased concentration of glucose during batch cultivation was found to produce a higher level of extracellular metabolites. Ethanol and glycerol were the main metabolites found prevalent during the fermentation. It was confirmed from the results that both the strain behaved as aerobic fermenting crabtree positive yeast strains and K. marxianus was found suitable for the applications that are aimed for production of ethanol with high productivity on glucose at higher temperatures.