Sucrose yeasts

The neurotoxin roquefortine appears to occur generally in blue cheeses, and has been detected39 in all sixteen varieties of cheese studied, in amounts up to 6.8 p.p.m. in most varieties isofumigaclavine A was also present, in amounts up to 4.7 p.p.m. In order to study more closely the toxicological properties of these compounds, four strains of P. roquefortii from blue cheeses have been grown in liquid media, with a view to optimizing neurotoxin production in one experiment, as much as 100 mg l-1 of roquefortine were produced after incubation for 16 days in a sucrose-yeast extract.40... 

Cleaning Up Since sucrose, yeast, and ethanol are all natural products, all solutions produced in this experiment contain biodegradable material and can be flushed down the drain after dilution with water. The limewater can be disposed of in the same way. The Celite filter aid can be placed in the nonhazardous solid waste container. 

The fermentation of sucrose by yeast, one of man s most beloved reactions, is irreversible and zero-order in sucrose (yeast acts as a catalyst). When 4g of sucrose (C12H22O11) in 500cm was fermented with 4g catalyst, the half-life observed was 30 min. 

Invertase (sucrasc) small intestine, yeast sucrose glucose and fructose 6 2 (gut) 4 8 (yeast)... 

Yeast contains a number of enzymes, more particularly inyertase and zymase. Invertase catalyses the hydrolysis of sucrose to glucose and fructose (cf. the catalysis of this reaction by acids, p. 369). 

Table 5 presents typical operating conditions and cell production values for commercial-scale yeast-based SCP processes including (63) Saccharomjces cerevisae ie, primary yeast from molasses Candida utilis ie, Torula yeast, from papermiU. wastes, glucose, or sucrose and Klujveromjces marxianus var fragilis ie, fragihs yeast, from cheese whey or cheese whey permeate. AH of these products have been cleared for food use in the United States by the Food and Dmg Administration (77). 

Fermentation Feedstock. Sucrose, in the form of beet or cane molasses, is a fermentation feedstock for production of a variety of organic compounds, including lactic, glutamic, and citric acids, glycerol, and some antibiotics. Lesser amounts of itaconic, aconitic, and kojic acids, as well as acetone and butanol, are also produced (41,51—53). Rum is made by fermentation of cane molasses. Beet and cane molasses are used for production of baker s and brewer s yeast (qv). 

The yield was highest with starch or dextrin, intermediate and about the same with sucrose, glucose, maltose and lactose and poorest with glycerol. Kanamycin was produced by media containing soybean meal, peanut meal, cottonseed meal, corn steep liquor, peptone, yeast extract or meat extract, with or without sodium nitrate. Commercially available soybean meal was recognized to be one of the best nitrogen sources. The addition of corn steep liquor, peptone, yeast extract or nitrate to the soybean meal promoted the production of kanamycin. 

Alternative Step D Reduction with a Reductate — Sucrose (1 kg) is dissolved in water (9 liters) in a 20-liter bottle equipped with a gas trap. Baker s yeast Saccharomyces cerevisiae, 1 kg) is made into a paste with water (1 liter) and added to the sucrose solution with stirring. After lively evolution of gas begins (within 1 to 3 hours), 3-morpholino-4-(3-tert-butylamino-2-oxopropoxy)-1,2,5-thiadiazole hydrogen maleate [1.35 mols, prepared by reaction of the 3-morpholino-4-(3-tert-butylamino-2-oxopropoxy)-1,2,5-thiadiazole with an equimolar quantity of maleic acid in tetrahydrofuran]. The mixture is allowed to stand until fermentation subsides, after which the bottle is kept in a 32°C incubator until all fermentation has ended (in approximately 1 to 3 days). The yeast is filtered off with addition of diatomaceous earth and the filtrate is evaporated to dryness to give S-3-mor-pholino-4/3-tert-butylamino-2-hydroxypropoxy)-1,2,5-thiadiazole, MP 195° to 198°C (as hydrogen maleate), according to U.S. Patent 3,619,370. 

All foe organisms listed would grow on foe sucrose in molasses. Candida utUis or Kluyveromyces fragilis would be foe best organisms to use, as they are food-grade yeasts with high growth rates. 

The subcellular location of PG was studied in cells disrupted by osmotic lysis through formation and disruption of sphaeroplasts from self-induced anaerobically-grown cells. A discontinuous sucrose-density gradient produced four bands labelled I, II, III and IV. Band I included many vesicles and a peak of alkaline phosphatase activity (a vacuolar marker in yeasts), NADPH cytochrome c oxidoreductase activity, an endoplasmic reticulum marker, and... 

The distinctive aroma of ammonia is often apparent in bakeries but not in the final product. Bakers yeast performs its leavening function by fermenting such sugars as glucose, fructose, maltose, and sucrose. The principal products of the fermentation process are carbon dioxide gas and ethanol, an important component of the aroma of freshly baked bread. The fermentation of the sugar, glucose—an example of a decomposition reaction — is given by the equation in Fig. 5.19.1. 

In an fermentation process of a solution containing sucrose, the enzyme in-vertase, present in yeast, acts as a catalyst to convert sucrose into a 1 1 mixture of glucose and fructose. Thus, sucrose is a disaccharide that hydrolyzes in the presence of certain bacteria to yield glucose and fructose. The ether linkage in sucrose is broken to yield two alcohols ... 

Optically pure a, . (R)-3-hydroxybutanoates can be obtained by alcoholysis of poly-(R)-3-hydroxybutanoate, a fermentation product of fructose by Alcaligones eutrophus.4 (S)-Ethyl 3-hydroxybutanoate in 84-87% ee can be synthesized in 57-67% yield on a decagram-scale by an Organic Syntheses procedure6 using bakers yeast reduction of ethyl 3-oxobutanoate with the aid of sucrose.7 In order to obtain enantioselectivity as high as 95-97% ee, the substrate concentration should be kept below 1 g/L.6... 

Dextran formation47 in media containing sucrose inhibits agglutination of yeast cells by L. agglutinans, a genetic mutation of L. mesenteroides. 

The specificity of levansucrase98 is dependent not only on the d-fructoside but also on the aldoside residue of the substrate. Neither inulin nor methyl D-fructofuranoside was hydrolyzed by levansucrase, and even when these two substrates were hydrolyzed by inulase (prepared from inulin-fermenting Torula yeast) or by yeast invertase respectively, no levan formation occurred with levansucrase. However, neither methyl D-fructofuranoside nor inulin inhibited levan formation from sucrose by levansucrase. No levan was formed from potassium D-glucose... 

Indirect evidence of the reversal of enzymic synthesis of levan has recently been obtained.10Ba Enzyme preparations from B. subtilis were shown to contain an enzyme capable of hydrolyzing levan (in addition to the levan-synthesizing enzyme) in a system composed of D-glucose, levan, yeast invertase (to hydrolyze sucrose formed) and the B. subtilis enzyme preparation. 

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