A xerophile () is an

extremophilic An extremophile (from Latin ' meaning "extreme" and Greek ' () meaning "love") is an organism that is able to live (or in some cases thrive) in extreme environments, i.e. environments that make survival challenging such as due to extreme temper ...

organism that can grow and reproduce in conditions with a low availability of water, also known as

water activity Water activity (''aw'') is the partial vapor pressure of water in a solution divided by the standard state partial vapor pressure of water. In the field of food science, the standard state is most often defined as pure water at the same tempera ...

. Water activity (a_w) is measured as the humidity above a substance relative to the humidity above pure water (Aw = 1.0). Xerophiles are "xerotolerant", meaning tolerant of dry conditions. They can often survive in environments with water activity below 0.8; above which is typical for most life on Earth. Typically xerotolerance is used with respect to matric drying, where a substance has a low water concentration. These environments include arid desert soils. The term osmotolerance is typically applied to organisms that can grow in solutions with high solute concentrations (salts, sugars), such as

halophiles The halophiles, named after the Greek word for "salt-loving", are extremophiles that thrive in high salt concentrations. While most halophiles are classified into the domain Archaea, there are also bacterial halophiles and some eukaryotic species, ...

. The common

food preservation Food preservation includes processes that make food more resistant to microorganism growth and slow the oxidation of fats. This slows down the decomposition and rancidification process. Food preservation may also include processes that inhibit ...

method of reducing water (

food drying Food drying is a method of food preservation in which food is dried (dehydrated or desiccated). Drying inhibits the growth of bacteria, yeasts, and mold through the removal of water. Dehydration has been used widely for this purpose since anci ...

) activities may not prevent the growth of xerophilic organisms, often resulting in

food spoilage Food spoilage is the process where a food product becomes unsuitable to ingest by the consumer. The cause of such a process is due to many outside factors as a side-effect of the type of product it is, as well as how the product is packaged and s ...

. Some

mold A mold () or mould () is one of the structures certain fungus, fungi can form. The dust-like, colored appearance of molds is due to the formation of Spore#Fungi, spores containing Secondary metabolite#Fungal secondary metabolites, fungal seco ...

and

yeast Yeasts are eukaryotic, single-celled microorganisms classified as members of the fungus kingdom. The first yeast originated hundreds of millions of years ago, and at least 1,500 species are currently recognized. They are estimated to constitut ...

species are xerophilic. Mold growth on bread is an example of food spoilage by xerophilic organisms. Examples of xerophiles include ''

Trichosporonoides nigrescens ''Moniliella'' is a genus of fungi in the subdivision Ustilaginomycotina. Some species of ''Moniliella'' can cause disease in humans and in cats. The genus includes the black, yeast-like fungi in the Basidiomycota, although the black, yeast-lik ...

'', ''

Zygosaccharomyces ''Zygosaccharomyces'' is a genus of yeasts in the family Saccharomycetaceae. It was first described under the genus ''Saccharomyces'', but in 1983, it was reclassified to its current name in the work by Barnett ''et al''. The yeast has a long his ...

'', and

cacti A cactus (, or less commonly, cactus) is a member of the plant family Cactaceae, a family comprising about 127 genera with some 1750 known species of the order Caryophyllales. The word ''cactus'' derives, through Latin, from the Ancient Greek ...

References

{{- Biology terminology Ecology terminology Extremophiles

See also

References