Acid, acetic butyric

Skin Inorganic acids (chromic, nitric) organic acids (acetic, butyric) inorganic alkalis (sodium hydroxide, sodium carbonate) organic bases (amines) organic solvents. Dusts Detergents salts (nickel sulphate, zinc chloride) acids, alkalis, chromates. ... 

Organic acids (acetic, butyric, propionic and citric acids)... 

Short-chain acyl-CoA synthetase activates short-chain fatty acids, acetic, butyric and propionic acid. The enzyme is present in both the cytosol and in the mitochondrial matrix of most tissues the activity is especially high in the liver and the colon. 

One product of the rumen fermentation, methane, is of no value to the ruminant. The major fermentation products used by the ruminant are the short-chain fatty acids, acetate, butyrate and propionate. Acetate and butyrate can be used for energy, but propionate is most useful for the synthesis of protein. If the fermentation could be shifted to reduce methane, acetate and butyrate production and to increase the propionate, the feed efficiency and growth rate could improved. 

Many other chemicals can be obtained from both yeast and bacteria fermentation of sugars and pulp mill effluents. Potential fermentation products from wood hydrolysates include acetone, organic acids (acetic, butyric, lactic), glycerol, butanediol, and others.42... 

A) Solubility. Test the solubility of the following acids acetic, butyric, n-capraic, stearic, and benzoic acids. 

Dietary fibre consists of all components of plant cell walls not digested by human alimentary enzymes. Chemically, fibre is a mixture of cellulose, lignin, heteropoly-saccharides (hemicelluloses), acidic polysaccharides and pectin. In the colon, bacteria hydrolyse up to 15% of cellulose and 70-95% of other polysaccharides giving rise to volatile gases and low molecular weight fatty acids (acetic, butyric etc.) which have weak laxative activity. In addition the cellulosic and non-cellulosic polysaccharides are hydrophilic and absorb large amounts of fluid from the gut lumen, increasing in bulk as they do so. This is exactly the... 

Important components of hard cheeses (Gouda type) include some carboxylic acid esters (ethyl butanoate, ethyl hexanoate), as well as carboxylic acids (acetic, butyric, isobutyric, valeric, isovaleric, 2-methylbutyric and caproic acids). Cheeses manufactured using bacteria of the genus Propionibacterium (such as Emmental and Gruyere) contain propionic acid and other lower fatty acids, methyl thioacetate, some oxocarboxylic acids, various alcohols, esters (such as ethyl butanoate), lactones (such as 8-decalactone), amines and other basic compounds (also skatole in addition to aliphatic amines), alkylpyrazines (e.g. 2-sec-butyl-3-methoxypyrazine), 4-hydroxy-2,5-dimethyl-2H-furan-3-one (furaneol), 2-ethyl-4-hydroxy-5-methyl-2H-furan-3-one (homofuraneol) and a range of other compounds. 

In most cases, tertiary alcohols do not react. A few lipases and esterases have a larger active site and react slowly with esters of tertiary alcohols [13]. Esters of straight chain carboxylic acids (acetate, butyrate) are the best substrates. Esters with substituents at the a-carbon (relative to the carboxylic add) and esters of... 

Particulate organics —> carbohydrates, proteins, fats amino acids, sugars, fatty acids Amino acids and sugars — butyrate, propionate, acetate Fatty acids —> acetate Butyrate, propionate —> acetate Acetate — CH4 H2, CO2 CH4 Batstone et al (2002)... 

PMMA is not affected by most inorganic solutions, mineral oils, animal oils, low concentrations of alcohols paraffins, olefins, amines, alkyl monohahdes and ahphatic hydrocarbons and higher esters, ie, >10 carbon atoms. However, PMMA is attacked by lower esters, eg, ethyl acetate, isopropyl acetate aromatic hydrocarbons, eg, benzene, toluene, xylene phenols, eg, cresol, carboHc acid aryl hahdes, eg, chlorobenzene, bromobenzene ahphatic acids, eg, butyric acid, acetic acid alkyl polyhaHdes, eg, ethylene dichloride, methylene chloride high concentrations of alcohols, eg, methanol, ethanol 2-propanol and high concentrations of alkahes and oxidizing agents. 

Butyric acid, the simple oxidation product of -butyraldehyde, is used chiedy in the production of cellulose acetate butyrate [9004-36-8]. Sheets of cellulose acetate butyrate are used for thermoformed sign faces, bUster packaging, goggles, and face shields. 

Cellulose acetate [9004-35-7], prepared by reaction of cellulose with acetic anhydride, acetic acid, and sulfuric acid, is spun into acetate rayon fibers by dissolving it in acetone and spinning the solution into a column of warm air that evaporates the acetone. Cellulose acetate is also shaped into a variety of plastic products, and its solutions are used as coating dopes. Cellulose acetate butyrate [9004-36-8], made from cellulose, acetic anhydride, and butyric anhydride in the presence of sulfuric acid, is a shock-resistant plastic. 

Cellulose activated with ethylenediarnine [107-15-3] is used to prepare high molecular-weight cellulose butyrate (23). Cellulose so activated has a larger measured surface area (120 m /g) than cellulose activated with acetic acid (4.8 m /g). The diamine is removed with water, followed by solvent exchange with acetic acid and butyric acid before esterification. 

Mixed esters containing the dicarboxylate moiety, eg, cellulose acetate phthalate, are usually prepared from the partially hydroly2ed lower aUphatic acid ester of cellulose in acetic acid solvent by using the corresponding dicarboxyhc acid anhydride and a basic catalyst such as sodium acetate (41,42). Cellulose acetate succinate and cellulose acetate butyrate succinate are manufactured by similar methods as described in reference 43. 

Cellulose acetate butyrate is not affected by dilute acids and alkalies or gasoline, but chlorinated solvents cause some swelhng. Nylons resist many organic solvents but are attacked by phenols, strong oxidizing agents, and mineral acids. 

In a typical process for manufacture on a commercial scale bleached wood pulp or cotton linters are pretreated for 12 hours with 40-50% sulphuric acid and then, after drying, with acetic acid. Esterification of the treated cellulose is then carried out using a mixture of butyric acid and acetic anhydride, with a trace of sulphuric acid as catalyst. Commercial products vary extensively in the acetate/ butyrate ratios employed. 

If butyric or propionic acids are included in the esterifying mixture, acetate butyrates and acetate propionates are formed. These, requiring less plasticizer, are tougher and more moisture resistant material for making automobile steering wheels. 

The natural esters present in essential oils are usually those of acetic, butyric, and valerianic acids, and in the case of geranium oil, tiglate acid. 

As previously discussed, solvents that dissolve cellulose by derivatization may be employed for further functionahzation, e.g., esterification. Thus, cellulose has been dissolved in paraformaldehyde/DMSO and esterified, e.g., by acetic, butyric, and phthalic anhydride, as well as by unsaturated methacrylic and maleic anhydride, in the presence of pyridine, or an acetate catalyst. DS values from 0.2 to 2.0 were obtained, being higher, 2.5 for cellulose acetate. H and NMR spectroscopy have indicated that the hydroxyl group of the methy-lol chains are preferably esterified with the anhydrides. Treatment of celliflose with this solvent system, at 90 °C, with methylene diacetate or ethylene diacetate, in the presence of potassium acetate, led to cellulose acetate with a DS of 1.5. Interestingly, the reaction with acetyl chloride or activated acid is less convenient DMAc or DMF can be substituted for DMSO [215-219]. In another set of experiments, polymer with high o -celliflose content was esterified with trimethylacetic anhydride, 1,2,4-benzenetricarboylic anhydride, trimellitic anhydride, phthalic anhydride, and a pyridine catalyst. The esters were isolated after 8h of reaction at 80-100°C, or Ih at room temperature (trimellitic anhydride). These are versatile compounds with interesting elastomeric and thermoplastic properties, and can be cast as films and membranes [220]. 

Polymer blends have been categorized as (1) compatible, exhibiting only a single Tg, (2) mechanically compatible, exhibiting the Tg values of each component but with superior mechanical properties, and (3) incompatible, exhibiting the unenhanced properties of phase-separated materials (8). Based on the mechanical properties, it has been suggested that PCL-cellulose acetate butyrate blends are compatible (8). Dynamic mechanical measurements of the Tg of PCL-polylactic acid blends indicate that the compatability may depend on the ratios employed (65). Both of these blends have been used to control the permeability of delivery systems (vide infra). 

The nature of the diet sets the basic pattern of metabohsm. There is a need to process the products of digestion of dietary carbohydrate, lipid, and protein. These are mainly glucose, fatty acids and glycerol, and amino acids, respectively. In ruminants (and to a lesser extent in other herbivores), dietary cellulose is fermented by symbiotic microorganisms to short-chain fatty acids (acetic, propionic, butyric), and metabohsm in these animals is adapted to use these fatty acids as major substrates. All the products of digestion are metabohzed to a common product, acetyl-CoA, which is then oxidized by the citric acid cycle (Figure 15-1). 

Muller E, K Fahlbusch, R Walther, G Gottschalk (1981) Formation of WV-dimethylglycine, acetic acid and butyric acid from betaine by Eubacterium limosum. Appl Environ Microbiol 42 439-445. 

OH3COOH + CHgCHgCHgCOOH CHgCOCHgCHgCHg + CO -f HgO Acetic acid n-Butyric acid Methyl n-propyl ketone... 

The predominant RO membranes used in water applications include cellulose polymers, thin film oomposites (TFCs) consisting of aromatic polyamides, and crosslinked polyetherurea. Cellulosic membranes are formed by immersion casting of 30 to 40 percent polymer lacquers on a web immersed in water. These lacquers include cellulose acetate, triacetate, and acetate-butyrate. TFCs are formed by interfacial polymerization that involves coating a microporous membrane substrate with an aqueous prepolymer solution and immersing in a water-immiscible solvent containing a reactant [Petersen, J. Memhr. Sol., 83, 81 (1993)]. The Dow FilmTec FT-30 membrane developed by Cadotte uses 1-3 diaminobenzene prepolymer crosslinked with 1-3 and 1-4 benzenedicarboxylic acid chlorides. These membranes have NaCl retention and water permeability claims. 

Aliphatic acids Formic, acetic, butyric, popionic, malic, citric, isocitric, oxalic, fumaric, malonic, succinic, maleic, tartaric, oxaloacetic, pyruvic, oxoglutaric, maleic, glycolic, shikimic, cis-aconitic, trans-aconitic, valeric, gluconic... 

Figure 4.18 A, separation of antihistanine and decongestant drugs by reversed-phase IPC. Mobile phase nethanol-water (1 1) containing 5 aM hexanesulfonate and 1 % acetic acid at a flow rate of 3 al/nin. B, separation and indirect OV detection of carboxylic acids by reversed-phase IPC. Coaponents 1 acetic acid, 2 = propionic acid, 3 butyric acid, 4 = valeric acid, 5 caproic acid, and S -. systea peak. Mobile phase 0.3 aM l-phenethyl-2-picoliniua in acetate buffer at pH 4.6.

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