Ethanol tolerance

Deitrich RA, Bludeau P, Erwin VG. Phenotypic and genotypic relationships between ethanol tolerance and sensitivity in mice selectively bred for initial sensitivity to ethanol (SS and LS) or development of acute tolerance (HAFT and LAFT). Alcohol Clin Exp Res 2000 24(5) 595—604. 

Many CNS depressants have some liability for dependence. This is typically greater with barbiturates, but lesser with benzodiazepines, and perhaps nonexistent in many antiseizure medications. CNS depressants produce tolerance when administered chronically, where increasingly larger doses are required to sustain the same level of effect. Further, a cross-tolerance often develops, where the tolerance is generalized to other CNS depressants. For example, a person with an ethanol tolerance will also display some tolerance to barbiturates. The therapeutic index tends to decrease as tolerance increases, so that the difference between an effective and toxic dose diminishes. Thus, tolerance to CNS depressants is accompanied by a smaller safety margin. 

The enzyme is also being studied for use in converting of biomass to ethanol for fuel usage. Prospects for the conversion of cellulolytic biomass to ethanol for fuel or as a fuel additive have improved within the last decade because of the development of methods for the fermentation of xylose, which can comprise as much as 50% of the fermentable sugars in these feedstocks. One of these methods uses xylose isomerase to convert xylose, which is difficult to ferment by ethanol-tolerant yeasts, to the fermentable sugar xylulose (12,13). 

The ethanol concentration in step 4 of the lysis protocol is a w/w concentration Ethanol solutions made up v/v, or otherwise in excess of 90% w/w, exceed the ethanol tolerance limits of some batches of nitrocellulose. Filters washed in such solutions may become brittle and be reduced nearly to powder by the end of the hybridization-color assay procedure. The appropriate solution can be made from 100% ethanol. 

The simultaneous bioconversion of mixed sugar syrups is one of the most ambitious challenges in the field of bioethanol production. Different productivities and ethanol-tolerance of the yeasts used in the fermentation of glucose and xylose (the most abundant biomass sugars) have led... 

Gao, C. and Fleet, G. H. (1988). The effects of temperature and pH on the ethanol tolerance of the wine yeasts, Saccharomyces cerevisiae, Candida stellata and Kloeckera apiculata. ]. Appl. Bacteriol. 65,405-410. 

Navratil, M., Sturdik, E., and Gemeiner, P. (2001). Batch and continuous mead production with pectate immobilised, ethanol-tolerant yeast. Biotechnol. Lett. 23, 977-982. 

In isolation and purification, although water is of course the main solvent, when alcohol is included, it acts as an antidispersant of the hydrocol-loidal solute. Acetone is preferable when treating ethanol-tolerant polysaccharides like cellulose derivatives. The most ethanol-tolerant polysaccharides have been precipitated from water by refrigerating a dispersion of each containing a high volume of acetone. 

In this laboratory, commercial samples of polysaccharides are routinely dispersed in water, then three times the volume of ethanol is added to precipitate them. Samples are finally rinsed with 95% ethanol. For the ethanol-tolerant polysaccharides, acetone dispersions are refrigerated at 0°C until the solvent and solute phases are visibly separate. 

Regardless of classification, polysaccharides express varying degrees of ethanol tolerance neutral species are mostly unresponsive to electrolytes, including weak acid, and protonated species precipitate with low solvent retention from strong acid and Ca2+ solutions. Exceptions to many general rules abound for example, polyacids are generally the most stable species,... 

Rosa, M.F., Sa Correia, I., and Novais, J.M., Improvements in ethanol tolerance of Kluyveromyces fragilis in Jerusalem artichoke juice, Biotechnol. Bioeng., 31, 705-710, 1988. 

Identification of genes involved in ethanol tolerance Bioethanol [344]... 

GA3P is subsequently converted, in a number of steps, into pyruvate (PYR), which is the branch-point between fermentation and respiration. Saccharomyces species are particularly well adapted to the anaerobic production of ethanol, via decarboxylation and reduction of PYR, to the near-exclusion of other metabolites. On account of this latter characteristic, as well as its high ethanol tolerance, Saccharomyces is the preferred organism to produce ethanol from hexoses. 

STY is high for a fermentative procedure and ranges from 140 g L-1 d 1 for a continuous tank reactor to 1.2 kg IT1 d 1 in a continuous tower reactor with cell recycle. Depending on the ethanol tolerance of the production species, ethanol is produced to a concentration of 12-20%. The ethanol is traditionally recovered from the fermentation broth via an energy-intensive distillation step, but it is sought to replace the latter by pervaporation or reversed osmosis [25]. 

Alexandre, H., Rousseaux, I., Charpentier, C. (1994) Relationship between ethanol tolerance, hpid composition and plasma membrane fluidity in Saccharomyces cerevisiae and Kloeckera apiculata. FEMS Microbiol. Lett., 124, 17-22... 

Aguilera, R, Peinado, R.A., Millan, C., Ortega, J.M., Mauricio, J.C. (2006). Relationship between ethanol tolerance, H+-ATPase activity and the lipid composition of the plasma membrane in different wine yeast strains. Int. J. Food Microbiol., 110, 34-42. 

Jimenez, J., Bemtez, T. (1987). Genetic analysis of highly ethanol-tolerant wine yeasts. Curr. Gen., 12, 421 28. 

Similar techniques were used by Shinohara et al (71) to develop hybrids with increased production of fusel alcohols and esters. Protoplast fusion techniques have been used to confer amylolytic activity to brewery yeasts (22) and ethanol tolerance to wine yeasts (70) Farris et al (72) used protoplast fusion to produce hybrids with killer factor that is, the ability to secrete proteinic toxins. Kunkee and coworkers (25) utilized a leucine auxotrophic mutant strain of S. cerevisiae (UCD Montrachet 522) to produce base wine for brandy production the mutant strain produces less isoamyl alcohol, reducing the quantity of fusel alcohols in the subsequent brandy. And Thornton (48) discussed the progress in utilizing plasmid vectors to introduce new genes into wine yeasts he cautioned, however, that until the yeast genome is better understood that direct gene manipulation techniques will be of limited value. 

Zinc deficiency in humans is difficult to diagnose because a suitable functional test, or a test for zinc reservoirs, has been lacking, Milne et ai. (1987) documented that a variety of zinc-requiring enzymes of the red blood cell seem to resist the effects of dietary zinc deficiency, but demonstrated that liver alcohol dehydrogenase may be sensitive to the deficiency. The activity of this enzyme was assessed by a functional test — the ethanol tolerance test. The ethanol tolerance test would be expected to be influenced by factors unrelated to zinc status, such as the state of Induchon of the ethanol oxidizing system, and hence may not be the functional test of choice for assessing zinc status. 

Warnings/precautions Additive sedative effects with other CNS depressants (ethanol) tolerance and dependence may develop with prolonged use Serotonin syndrome may occur with other serotonergic drugs (i.e. MAO inhibitors) SSRIs may inhibit CYP450 liver enzymes ... 

One example of whey utilization technologies is the production of alcohol from cheese whey at the Carbery Milk Products Ltd. factory, Ballineen, Ireland. The Carberry plant produces 2.59% v/v of ethanol from 4.7 w/v of lactose in whey permeate (Barry, 1982). Because the Kluveromyces species, used in anaerobic fermentations, have low ethanol tolerance, preconcentration of the lactose is not possible, so fermentation and distillation costs are considerable. Under Irish conditions potable alcohol is the most profitable outlet but in other countries, anhydrous alcohol for industrial or power uses may be more attractive (Ozmihci and Kargi, 2008). 

Various strains of the AAB are ethanol-tolerant, and the majority of strains have been found to be able to grow at 5% v/v ethanol, and some even at 10%. Glucose tolerance has often been described in various AAB, and is frequently found in strains isolated from traditional balsamic vinegar. One of the inhibiting substances for acetic acid bacteria is high... 

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