Production of Polyols by Osmotolerant Yeasts

The growth of microbial cells is often inhibited in environments where the water activity is much reduced. However, some microorganisms have developed various strategies in order to resist the stresses to which they are exposed. The ability to adapt to fluctuations in external osmolarity and the mechanisms of osmoregulation have been elucidated in some of them (1 ). Thus, both prokaryotic and eukaryotic microorganisms include species that can tolerate a wide range of salt concentrations and/or sugars in the culture medium during growth; they are called osmotolerant (2 ).