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Alcohol, denatured solutions

In the past, dissociation of the nucleoprotein complex has been brought about by salt solutions or by heat denaturation,129 but, more recently, decomposition has been effected by hydrolysis with trypsin,126 or by the use of dodecyl sodium sulfate130 or strontium nitrate.131 Some virus nucleoproteins are decomposed by ethyl alcohol.132 This effect may be similar to that of alcohol on the ribonucleoproteins of mammalian tissues. If minced liver is denatured with alcohol, and the dried tissue powder is extracted with 10% sodium chloride, the ribonucleoproteins are decomposed to give a soluble sodium ribonucleate while the deoxyribonucleoproteins are unaffected.133 On the other hand, extraction with 10 % sodium chloride is not satisfactory unless the proteins have first been denatured with alcohol. Denaturation also serves to inactivate enzymes of the tissues which might otherwise bring about degradation of the nucleic acid during extraction. [Pg.309]

Ammoniacal ethanol is prepared by chilling ten liters of anhydrous denatured ethyl alcohol as commercially purchased in a freezer to well below 0° C. Next, 600 to 750 ml of liquid ammonia is drawn from a pressure cylinder into a 1000 ml graduate in a well ventilated area. The contents of the graduate are carefully poured into the chilled alcohol. The solution is then stirred to mix and warmed to room temperature. The solution should be at least two molar as determined by titration against standard acid solution to a methyl red endpoint. If titration is to be attempted, a little methyl red should be added to the chemical list. [Pg.135]

Caustic potash Chloric acid Chlorine, dry Chloroacetic acid Chloroacetone Chloroform Chlorosilanes Chlorosulfonic acid Chromic acid Chromic chloride Chromic fluorides Chromic hydroxide Chromic nitrates Chromic oxides Chromic phosphate Chromic sulfate Coconut oil Cod liver oil Coke oven gas Copper carbonate Copper chloride Copper cyanide Copper nitrate Copper oxide Copper sulfate Corn oil Coconut oil Cresylic acid Crude oil Cutting oils Cyclohexane Cyclohexanol Cyclohexanone Cyclohexene Denatured alcohol Detergent solution Dex train Dextrose Diacetone Diallyl ether Diallyl phthalate Dichloroacetic acid Dichloroaniline o-Dichlorobenzene Dichloroethane Dichloroethylene Dichloromethane Dichlorophenol Diesel oil... [Pg.552]

Differential scanning calorimetry has been used to investigate changes in the conformation of hen egg-white lysozyme brought about by the combined actions of temperature and denaturants. The effects of a wide range of alcoholic denaturants indicated that hen egg-white lysozyme, whether in solution or in crystalline form, displays structural features that are generally strikingly similar. [Pg.417]

Water and alkoxides are not miscible so that a co-solvent, usually the parent alcohol, is currently added in order to mix both reagents and get a clear solution. However alcohol denatures proteins so that such a solvent should be avoided when mixing water and alkoxides. Actually alcohol has been shown to be an unnecessary additive in the silicon sol-gel chemistry (Avnir, 1987). Hydrolysis occurs at the water/silane interface giving alcohol as a reaction product. The mixture then becomes rapidly homogeneous even if unstirred. Better mixing and faster hydrolysis are obtained when the preparation is sonicated before adding proteins (Ellerby, 1992). Hydrolysis is usually performed under acid conditions... [Pg.485]

Dry Zein was dissolved in a mixture of ethyl alcohol (denatured) and glycerol (ethyl alcohol 40 g /lOg of Zein and glycerol 4g/10g) with a magnetic stirrer. The solution was cast into sheets on a smooth (glass) surface. Prior to casting, the glass was coated with a standard mold release agent. The sheets were harvested after 48 hrs of open air solvent evaporation. [Pg.1847]

Added 100 grams denatured alcohol, no layer formed as the oily product is miscible in ethanol. Added 20 grams of C//-/2O. This pulled the ethanol and other product into the top layer, bottom layer containing some ethanol and safrole. Separated layers, placed the oily bottom layer into a 2-liter breaker. Took the temp right to 234 C. The ethanol and water came off <=100 C... The safrole started to boil 232C, then came to a full boll and maintained 234 C. Product ui/as yellow orange in color, suitable for whatever purpose one has in mind BTW, after the safrole cooled, she checked it with a 5% NaOH solution to see if any eugenol ivas left behind, no participate formed. [Pg.38]

Astringents are designed to dry the skin, denature skin proteins, and tighten or reduce the size of pore openings on the skin surface. These products can have antimicrobial effects and are frequendy buffered to lower the pH of skin. They are perfumed, hydro-alcohoHc solutions of weak acids, such as tannic acid or potassium alum, and various plant extracts, such as bitch leaf extract. The alcohol is not only a suitable solvent but also helps remove excess sebum and soil from the skin. After-shave lotions generally function as astringents. [Pg.298]

Ethanol water is a solution of denatured grain alcohol. Its main advantage is that it is nontoxic and thus is widely used in the food and chemic industry. By using corrosion inhibitors it could be made non-corrosive for brine service. It is more expensive than methanol water and has somewhat lower heat transfer coefficients. As an alcohol derivate it is flammable. [Pg.1125]

Product recoveiy from reversed micellar solutions can often be attained by simple back extrac tion, by contacting with an aqueous solution having salt concentration and pH that disfavors protein solu-bihzation, but this is not always a reliable method. Addition of cosolvents such as ethyl acetate or alcohols can lead to a disruption of the micelles and expulsion of the protein species, but this may also lead to protein denaturation. These additives must be removed by distillation, for example, to enable reconstitution of the micellar phase. Temperature increases can similarly lead to product release as a concentrated aqueous solution. Removal of the water from the reversed micelles by molecular sieves or sihca gel has also been found to cause a precipitation of the protein from the organic phase. [Pg.2061]

Aqueous solutions are not suitable solvents for esterifications and transesterifications, and these reactions are carried out in organic solvents of low polarity [9-12]. However, enzymes are surrounded by a hydration shell or bound water that is required for the retention of structure and catalytic activity [13]. Polar hydrophilic solvents such as DMF, DMSO, acetone, and alcohols (log P<0, where P is the partition coefficient between octanol and water) are incompatible and lead to rapid denaturation. Common solvents for esterifications and transesterifications include alkanes (hexane/log P=3.5), aromatics (toluene/2.5, benzene/2), haloalkanes (CHCI3/2, CH2CI2/I.4), and ethers (diisopropyl ether/1.9, terf-butylmethyl ether/ 0.94, diethyl ether/0.85). Exceptionally stable enzymes such as Candida antarctica lipase B (CAL-B) have been used in more polar solvents (tetrahydrofuran/0.49, acetonitrile/—0.33). Room-temperature ionic liquids [14—17] and supercritical fluids [18] are also good media for a wide range of biotransformations. [Pg.134]

A. Ethyl Nitrite.—Two solutions are prepared. Solution I contains 620 g. (9 moles) of sodium nitrite (650 g. of technical 95 per cent), 210 g. (4.57 moles) of alcohol (285 cc. of 90 per cent denatured, or its equivalent) and water to make a total volume of 2500 cc. Solution II contains 440 g. of sulfuric acid (255 cc. of sp. gr. 1.84) and 210 g. of alcohol, diluted with water to 2500 cc. Ethyl nitrite may he generated cont inuously in gaseous form by allowing solution II to (low into solution I. [Pg.12]

The two-stage procedure eliminates the detrimental effect of acid, but an alcohol, which is produced in the course of precursor hydrolysis Equation (2), remains in solution. This can cause unfolding of the biomacromolecule and denaturation of... [Pg.82]

The main advantage is that the entrapment conditions are dictated by the entrapped enzymes, but not the process. This includes such important denaturing factors as the solution pH, the temperature and the organic solvent released in the course of precursor hydrolysis. The immobilization by THEOS is performed at a pH and temperature that are optimal for encapsulated biomaterial [55,56]. The jellification processes are accomplished by the separation of ethylene glycol that possesses improved biocompatibility in comparison with alcohols. [Pg.101]

Adsorbents for biomacromolecules such as proteins have special properties. First, they need to have large pore sizes. A ratio of pore radius to molecule radius larger than 5 is desirable to prevent excessive diffusional hindrance (see Intraparticle Mass Transfer in this section). Thus, for typical proteins, pore radii need to be in excess of 10-15 nm. Second, functional groups for interactions with the protein are usually attached to the adsorbent backbone via a spacer arm to provide accessibility. Third, adsorbents based on hydrophilic structures are preferred to limit nonspecific interactions with the adsorbent backbone and prevent global unfolding or denaturation of the protein. Thus, if hydrophobic supports are used, their surfaces are usually rendered hydrophilic by incorporating hydrophilic coatings such as dextran or polyvinyl alcohol. Finally, materials stable in sodium hydroxide solutions (used for clean-in-place) are... [Pg.9]

Biocatalysis has traditionally been performed in aqueous environments, but this is of limited value for the vast majority of nonpolar reactants used in chemical synthesis. For a long time it was assumed that all organic solvents act as denaturants, primarily based on the flawed extrapolation of data obtained from the exposure of aqueous solutions of enzyme to a few water-miscible solvents, such as alcohols and acetone, to that of all organic sol vents. [Pg.54]

Denatured Alcohol 2,4-D Esters Detergent Alkylate = 2 Dextrose Solution Diacetic Ether Diacetone Diacetone Alcohol Diacetylmethane Diacetyl Peroxide Solution... [Pg.39]


See other pages where Alcohol, denatured solutions is mentioned: [Pg.5]    [Pg.5]    [Pg.343]    [Pg.324]    [Pg.157]    [Pg.315]    [Pg.67]    [Pg.226]    [Pg.264]    [Pg.368]    [Pg.208]    [Pg.400]    [Pg.272]    [Pg.547]    [Pg.132]    [Pg.123]    [Pg.428]    [Pg.25]    [Pg.26]    [Pg.217]    [Pg.1570]    [Pg.81]    [Pg.201]    [Pg.368]    [Pg.370]    [Pg.67]    [Pg.197]    [Pg.325]    [Pg.167]    [Pg.44]    [Pg.221]    [Pg.274]   
See also in sourсe #XX -- [ Pg.3 , Pg.3 , Pg.5 ]




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Alcohol denaturation

Alcohol solution

Alcoholic solutions

Denatured alcohol

Solution denaturation

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