effect of growth medium on the levels of trehalose and glycogen content of some yeasts

Yeast cells of Saccharomyces cerevisiae as well as the osmotolarant yeasts Saccharomyces rouxii and Debaryomyces hansenii were grown aerobically and anaerobically. The water activity of the growth medium was regulated either by sodium chloride or glycerol. Levels of trehalose of most of the yeasts decreased with the reduction of water activity of the growth media in the presence of glycerol or sodium chloride when the yeast cells were grown under both aerobic and anaerobic conditions. However, the levels of glycogen in mast cases showed a reciprocal relationship when the yeast cells were grown either aerobically or anaerobically in the presence of either glycerol or sodium chloride