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→Debaryomyces Hansenii
''D Hansenii'' is the most prevalent yeast in dairy and meat products as well as early stages of soy sauce fermentation. Various isolates exist originating from cheese, sake moto, edomiso, rennet, psoriasis, infected hands and salmon. In general, ''D. hansenii'' can be found in habitats with low water activity as well as in products with high sugar concentrations. Although ''D. hansenii'' is considered a non-pathogenic yeast, various clinical cases of ''D. hansenii'' exist. This yeast was originally isolated from saline environments and is maybe one of the most osmotolerant (can tolerate high levels of salt and sugar) yeasts in existence. <ref name="Eureka D. Hansenii">[https://eurekabrewing.wordpress.com/2014/04/18/hello-my-name-is-debaryomyces-hansenii/ . Eureka Blog's Post on D. Hansenii, Retrieved 8/9/2017]</ref>
=====General Information=====
As already mentioned, ''D. hansenii'' can tolerate very high levels of salt. Some sources cite salinity levels up to 24% whereas ''Saccharomyces cerevisiae'' commonly tolerate levels up to 10%. Such high tolerances are not that common in living organisms and can be used on industrial scale by cultivating ''D. hansenii'' at high salt levels to prevent the growth of other yeasts (quasi non-sterile production conditions). Beside dealing with high osmolarities, ''D. hansenii'' secrete toxins capable of killing other yeasts.
Although this yeast is already an extremophile(an organism that thrives in physically or geochemically extreme conditions that are detrimental to most life on Earth) in terms of osmolarity, it does not stop there. Besides the normal sugars, ''D. hansenii'' is capable of metabolizing n-alkanes, melibiose, raffinose, soluble starch, inositol, xylose, lactic acid and citric acid. Furthermore, this yeast can form arabitol(a sugar alcohol) as well as riboflavin (vitamin B2). ''D. hansenii'' is therefore used on industrial scale to produce vitamin B2 and has a big potential for other biotechnological processes.
''D. hansenii'' is a very common yeast in cheeses and seems to have a major impact on the development of the microflora as well as the taste. As previously mentioned, ''D. hansenii'' can metabolize lactic acid, citric acid and galactose. The metabolization of lactic acid by yeasts has been shown to have an impact on the bacterial flora of the cheese in types such as Limburger, Tilsiter, Port Salut, Trappist, Brick and the Danish Danbo. Furthermore, ''D. hansenii'' forms volatile compounds associated with a “cheesy” flavor. For example, ''D. hansenii'' seems to have a major role in the development of Cheddar and Camembert cheese by synthesizing S-methylthioacetate (most prevalent volatile sulfur compound found in cheese).<ref name="Eureka D. Hansenii"></ref>
====Debaryomyces Nepalensis====