Key Concepts:
Xerophiles have requirement for reduced water activity; fungi are the most successful xerophilic organisms, and the most extreme xerophiles are found among fungi.
Compatible solutes are accumulated intracellularly to maintain the osmotic balance in response to decreased water availability.
Glycerol is the primary compatible solute among xerophilic fungi.
Membrane composition plays an important role in retaining glycerol within the cells of xerophiles.
Moderate xerophiles of the genera Aspergillus, Eurotium and Penicillium are economically important spoilage organisms.
Some xerophiles are isolated from both high-salt and high-sugar environments; others have a preference for either salt or sugar.
Xerophiles can cause spoilage of food and feed: stored commodities, sugary products and salted foods.
Xerophilic species are widely spread on the fungal tree of life.