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alphabetized yeasts by genus
==Yeasts==
===''Debaryomyces'' spp.===[[File:ZygosaccharomycesD hansenii.jpg|thumb|Debaryomyces hansenii; photo by [http://www.gettyimages.co.uk/detail/photo/debaryomyces-hanseni-yeast-high-res-stock-photography/128615807].]] ''Debaryomyces'' is a genus of yeast commonly referred to as a spoilage yeast <ref>[https://en.wikipedia.org/wiki/Debaryomyces Wikipedia. Debaryomyces. Retrieved 09/03/2015.]</ref>. The non-pathogenic species ''D. hansenii'' is commonly found in cheese, and is an osmotolerant, halotolerant, and xerotolerant (tolerant high amounts of salt and sugar, and low amounts of water) <ref>[https://en.wikipedia.org/wiki/Debaryomyces_hansenii Wikipedia. Debaryomyces hansenii. Retrieved 09/03/2015.]</ref>. ====''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. <ref name="Eureka D. Hansenii"></ref> 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. <ref name="Eureka D. Hansenii"></ref> ''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''==== ''Debaryomyces nepalensis'' is an osmotolerant yeast isolated from rotten apples that is known to utilize both hexoses and pentoses and produce industrially important metabolites like ethanol, xylitol and arabitol. <ref name="D. Nepalensis1">[https://www.ncbi.nlm.nih.gov/pubmed/18810540 . Production of ethanol and arabitol by Debaryomyces nepalensis: influence of process parameters. Himabindu Kumdam, Shweta Narayana Murthy and Sathyanarayana N Gummadi. 2013.]</ref> =====Sugar Utilization and Ethanol Creation===== {| class="wikitable sortable"|-! Carbon Source !! Carbon Source Consumed (g/L) !! Ethanol Created (g/L)|-| Sucrose || 82.00 || 9.90|-| Glucose || 84.75 || 9.05|-| Arabinose || 86.70 || 2.43|-| Fructose || 80.40 || 9.84|-| Glycerol || 50.60 || 0.77|-|}<ref name="D. Nepalensis1"></ref> =====General Information===== '''Effect of nitrogen sources''' The organism was grown in the presence of different sources of nitrogen like, ammonium sulphate, nitrates and nitrites along with yeast extract and its ability to produce ethanol and arabitol was studied. Among them ammonium sulphate served as the best nitrogen source, whereas, in the presence of nitrites and nitrates, the organism failed to metabolize glucose efficiently. Yeast extract proved to be an integral source of amino acids and other vitamins for growth, without which, the organism had low efficiency for its metabolism. <ref name="D. Nepalensis1"></ref> ===''Lachancea'Zygosaccharomyces rouxii'=== ===''Pichia''===[[File:Pichia.png|thumb|Pichia membranaefaciens; photo by [httphttps://www.researchgate.net/figure/278707172_fig3_Figure-8-08-Pichia-membranaefaciens-a-colonies-on-MEA-7-d-25C-bar-2-mm-b ].]] ''Pichia'' is a genus of yeasts in the family Saccharomycetaceae with spherical, elliptical, or oblong cells. ''Pichia'' is a teleomorph, and forms hat-shaped, hemispherical, or round ascospores during reproduction. The anamorphs of some ''Pichia'' species are ''Candida'' species. The asexual reproduction is by multilateral budding. ''Pichia'' can be prolific pellicle-forming yeasts. <ref name="Pichia wiki">[https://microbialfoodsen.wikipedia.org/microbewiki/Pichia . Wikipedia, Obtained 8/1/17]</ref> [[File:Pichiakpellicle.jpg|thumb|Pichia kudriavzevii pellicle; photo by Dr Matt Bochman [https://www.facebook.com/539527212902201/photos/a.686127604908827.1073741828.539527212902201/686127568242164/?type=1&theater ].]] ====''Pichia kudriavzevii''==== ''P. kudriavzevii'' is a very abundant yeast found in soil, fruits, and various fermented beverages. It is ovoid to elongate in shape. So far, ''P. kudriavzevii'' is mainly associated with food spoilage to cause surface biofilms in low pH products. It is also known for known for creating a very heavy pellicle. <ref name="pichia k1">[https://eurekabrewing.wordpress.com/2014/02/16/hello-guidemy-zygosaccharomycesname-rouxiiis-pichia-kudriavzevii/ Microbial Foods.orgPichia k Info. Source: Eureka Brewing Blog.]</ref> '''Sugar Utilization''' ''P. kudriavzevii'' can mainly metabolize glucose making it a non-viable strain for primary fermentations. During trials it was unable to metabolize galactose, sucrose, maltose, lactose, raffinose, and trehalose. <ref name="pichia k1"></ref> Interestingly, some strains of ''P. kudriavzevii'' can metabolize pentose sugars such as xylose <ref name ="P. kudriavzevii xylose">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3485917/. [Genome Sequence of Pichia kudriavzevii M12, a Potential Producer of Bioethanol and Phytase.]</ref>. ====''Pichia apotheca''==== ''Pichia apotheca'' is a new hybrid species of ''Pichia'' which was identified in 2017. <ref name="pichia a">[http://www.biorxiv.org/content/biorxiv/early/2017/06/15/150722.full.pdf . Identification of Pichia apotheca. Authors: Caiti Smukowski Heil, Joshua N. Burton, Ivan Liachko, Anne Friedrich, Noah A. Hanson, Cody L. Morris, Joseph Schacherer, Jay Shendure, James H. Thomas, Maitreya J. Dunham. 2017.]</ref> ''Pichia apoteca'' was identified as a hybrid of ''Pichia membranifaciens'' and another unidentified species of ''Pichia''.
===''Zygosaccharomyces'' sp.==Characterization=====
During the study, a fermentation using solely ''ZygosaccharomycesPichia apoteca'' sp was conducted. belongs to the group of hemiascomycetous (class of fungi in which no ascocarps are formed) yeasts with a high tolerance to osmotic stressThe test wort used was at 13. This typical feature enables it to grow in environments with high concentrations of salts 75 degrees Plato and/or sugars, iafter 5 weeks at 13.e61 degrees Plato. under conditions restrictive The alcohol by weight was found to most other yeast speciesbe 0. ''Z02% after fermentation. bailii''In addition to this, ''Z. bisporous''percentages based on the entire contents of the wort showed that over five weeks, ''Zglucose levels dropped from 1. rouxii'', and ''Z62% to 1. florentinus'' are species which have been isolated in grape musts or wine22%. Some strains can be very tolerant to a wide range of stressorsThe hybrid may incrementally breakdown maltotriose and fructose, including 50dropping from 1.46% sugar, 2to 1.505% acetic acid, 18% ethanol, and pH 20.57% to 0. It is also resistant 22% respectively, but did not appear to be able to preservatives commonly used in beverage production such as SOreduce the levels of maltose. These results indicate that the ''Pichia'' hybrid did not significantly metabolize much of the available carbohydrates into alcohol within this wort environment. <subref name="pichia a">2</subref>.
===''Toluraspora delbrueckii''===
[[File:aaaaaa.jpg|thumb|''Tolurspora delbrueckii''; photo by [https://fermentationstations.wordpress.com/2016/09/26/candida-milleri-stiven-mita/ ].]]
''Toluraspora delbrueckii'' is species of yeast, that is round to ovoid in shape and has been traditionally used in some wine fermentations to increase the complexity. Most of the commercial ''Torulaspora'' species and strains were isolated from soil, fermenting grapes (wine), berries, agave juice, tea-beer, apple juice, leaf of mangrove a tree, moss, lemonade and tree barks. Although it was said that most ''T. delbrueckii'' strains would not fully attenuate or tolerate higher alcohol contents it has been shown that this property is strain-dependent.
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===''Wickerhamomyces'' spspp.===
See: ''Pichia'' spspp.
===''LachanceaZygosaccharomyces''spp.===[[File:Zygosaccharomyces.jpg|thumb|''Zygosaccharomyces rouxii''; photo by [http://microbialfoods.org/microbe-guide-zygosaccharomyces-rouxii/ Microbial Foods.org].]]
==Bacteria==