Yeast Carbon Base

Following suppliers instructions, prepare yeast carbon base (YCB) and add agar at 2% (wt/vol). Dissolve fully in boiling waterbath and dispense 15-20-mL aliquots into stoppered test tubes and autoclave per recommendations. 

Potato dextrose agar Tween-80 Tryptone WL-nutrient agar WL-differential agar Wort agar Yeast carbon base Yeast extract YM agar YM broth... 

Assimilation tests for carbon compounds use yeast nitrogen base (YNB) without carbon sources, and the assimilation test for nitrogen compounds use yeast carbon base (YCB) without assimilable nitrogen sources. For the tests described, YNB without amine acids and ammonium sulfate is used (Anonymous, 1984). Carbon sources normally examined include a number of pentoses, hexoses, disaccharides, trisaccharides, polysaccharides, alcohols, organic acids, and glycosides as specified by Yarrow (1998). Nitrogen sources commonly tested include nitrate, nitrite, ethyl-amine hydrochloride, cada-verine dihydrochloride, L-lysine, imidazole, glucosamine, creatine, and creatinine. When nitrite is used as a test compound, it is necessary to adjust the pH of the medium to 6.5 because toxic nitrous acid is formed at pH <6.0. 

Carbon-based blacks group Antler Antlerite Bitumen Bone Coal Indigo Hydroxylapatite Yeast Animal black Atramentum Black toner Boija black Drop black, Franlfort black German black Ivory black Paris black, Wine lees black... 

Carbon-based blacks group Cokes sub-group Tbast Drop black, Frankfort Mack, Wine lees black. Yeast black Heaton (1928) 381 Osborn (1845) 40... 

See carbon-based blacks group cokes sub-group yeast Frankfort black and German black. 

Both alkanes and gas oil can be used as carbon and energy sources. Commercially, Candida tropicalis and Candida lipolytica have been used (35,36). The fermentation contains two immiscible Hquid phases (the alkane and the water) the semisoHd yeast and the gaseous air phase. In contrast to yeasts grown on carbohydrates, where maximum yields are 50%, yeasts grown on alkanes generally give yields of 95—105% based on the weight of the alkane. 

Fermentation tests are based on the ability of yeast to oxidize the sugar to yield ethanol and carbon dioxide, although only the D-isomers are fermentable and only relatively few of these. Modem chromatographic techniques are, however, much more acceptable and paper and thin-layer techniques are useful for routine separation and semi-quantitation of carbohydrate mixtures, although GLC or HPLC techniques may be necessary for the more complex samples or for quantitative analysis. 

When a sucrose- or other simple carbohydrate-based solution is mixed with yeast and oxygen in a fermenter, carbon dioxide vapour and alcohol are produced. The carbon dioxide can then be passed through a separator to remove any trace cany-over of foam. Once the foam has been removed the carbon dioxide is compressed. It is then scrubbed with water in a packed tower, removing water-soluble impurities such as alcohol, ketones and other aroma chemicals produced during fermentation. 

Representatives of all kinds have been explored for synthetic applications while mechanistic investigations were mainly focussed on the distinct FruA enzymes isolated from rabbit muscle [196] and yeast [197,198]. For mechanistic reasons, all DHAP aldolases appear to be highly specific for the donor component DHAP [199], and only a few isosteric replacements of the ester oxygen for sulfur (46), nitrogen (47), or methylene carbon (48) were found to be tolerable in preparative experiments (Fig. 7) [200,201], Earlier assay results [202] that had indicated activity also for a racemic methyl-branched DHAP analog 53 are now considered to be artefactual [203]. Dihydroxyacetone sulfate 50 has been shown to be covalently bound via Schiff base formation, but apparently no a-deprotonation occurred as neither H/D-exchange nor C-C... 

Prior to 1941, mj/o-inositol was often determined by isolation, as such or as the hexaacetate.87 The isolated inositol was weighed, or was oxidized to carbon dioxide (which was measured in a gas buret).92 In 1941, Woolley98 published his microbiological method, in which the yeast Saccharomyces cerevisiae was used as a test organism. Soon afterward, there appeared an improved procedure, using Saccharomyces carlsbergensis,9i 96 and an additional method based on the discovery of an inositol-less mutant of the common bread-mold, Neurospora crassa.96-98 Plundreds of types of foods,... 

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