Acids Constitution

Solubility. At long oil lengths, the aUphatic hydrocarbon chains of the fatty acids constitute the major portion of the mass of the reski molecules therefore, the reski is soluble ki nonpolar aUphatic solvents. Conversely, as the oil length decreases and the phthaUc content kicreases, the aromaticity of the reski molecules kicreases, and the aromaticity and/or the polarity of the solvent must be kicreased ki order to dissolve the reski effectively. 

The enzymatic hydrolysates of milk casein and soy protein sometimes have a strong bitter taste. The bitter taste is frequently developed by pepsin [9001 -75-6] chymotrypsin [9004-07-3] and some neutral proteases and accounted for by the existence of peptides that have a hydrophobic amino acid in the carboxyhc terminal (226). The relation between bitter taste and amino acid constitution has been discussed (227). 

Naphthenic acids constitute about 50 wt% of the total acidic compounds in crude oils. Naphthenic-based crudes contain a higher percentage of naphthenic acids. Consequently, it is more economical to isolate these acids from naphthenic-based crudes. 

Cresylic acid is a commercial mixture of phenolic compounds including phenol, cresols, and xylenols. This mixture varies widely according to its source. Properties of phenol, cresols, and xylenols are shown in Table 4-5 Cresylic acid constitutes part of the oxygen compounds found in crudes that are concentrated in the naphtha fraction obtained principally from naphthenic and asphaltic-based crudes. Phenolic compounds, which are weak acids, are extracted with relatively strong aqueous caustic solutions. 

Historically the Strecker synthesis of a-amino acids constitutes the first chemical access to this important class of compounds1, In this process, an aldehyde reacts with ammonia and hydrogen cyanide to form an a-amino nitrile2 which subsequently is hydrolyzed to give the corresponding amino acid3... 

A wide variety of bases, nucleosides and nucleotides have been separated using porous layer bead ion exchangers. A representative chromatogram of the separation of ribonucleoside mono-phosphoric acids from the work of Smukler ( ) is shown in Figure 4. Recently, ion exchangers chemically bonded to small particle diameter (> 10 ym) silica have been successfully applied to the separation of nucleic acid constitutents (37). The rapid separations using such supports undoubtedly mean that they will find increasing use in the future. 

Shioiri-Nakano, K. Tadokoro, I. Kudo, M. Instrumental analysis of streptococcal components. I. Carbohydrate and fatty acid constitution of hemolytic streptococci. Jap. J. Exper. Med. 1966,36, 563-576. 

The virus genome We have stated that the virus genome consists of either DNA or RNA, never both. Viruses differ in size, amount, and character of their nucleic acid. Both single-stranded and doublestranded nucleic acid is found in viruses, and the amount of nucleic acid per virion may vary greatly from one virus type to another. In general, in enveloped viruses the nucleic acid constitutes only a small part of the mass of the virus particle (1-2 percent), whereas in nonenveloped viruses the percent of the particle which is nucleic acid is much larger, often 25-50 percent. 

Hydroxamic acids constitute an important class of siderophores, which play a major role in iron solubilization and transport. Some of them are important as therapeutic agents. The Michael addition of nitroacetyl proline esters to allyl acrylate followed by Pd(0)-catalyzed intramolecular allyl transfer and subsequent reduction of the nitro group yields a novel class of cyclic hydroxamic acids related to pyroglutamic acid (Scheme 5.9).85... 

The unique suberin components that are not found as significant components of cutin are the very long chain molecules and the dicarboxylic acids. Therefore, chain elongation and conversion of co-hydroxy acids to the corresponding dicarboxylic acids constitute two unique biochemical processes involved in the synthesis of suberin. Incorporation of labeled acetate into the very long chain components of suberin was demonstrated and this ability developed during suberization in potato tuber disks [73]. The enzymes involved... 

Oxides of chlorine are both more numerous and more useful than those of fluorine. These oxides are the anhydrides of several important acids, and the oxyanions of those acids constitute the hypochlorites, chlorites, chlorates, and perchlorates. The first oxide of chlorine, C120 (m.p. -20 °C, b.p. +2 °C), contains chlorine in the +1 oxidation state. It can be prepared by the reaction... 

Amino acid analysers based on ion exchange resins are available commercially. These achieve good separations of amino acid mixtures. Fluorescent derivatives of separated amino acids constitute a very sensitive means of detecting these compounds in seawater [256,258]. Fluorescent derivatives that have been studied include o-phthalaldehyde [259], dansyl [260], fluo-rescamine [261], and ninhydrin [261]. 

As with other reactions, silyl esters of phosphorus acids constitute an important and useful category of reagents for conjugate addition reactions. With aldehydes, ketones, and esters, the silyl ester linkage is transferred to the carbonyl oxygen, facilitating the completion of the reaction, generating the free carbonyl or ester upon workup with a protic solvent (Equation 3.25). 

The first reaction proceeds most easily with hydrogen iodide since in many cases mere saturation with the gaseous acid suffices to bring it about. Hydrogen bromide reacts with greater difficulty, and in its case it is frequently necessary to heat the alcohol saturated with this acid in a sealed tube. The preparation of ethyl bromide described above, in which the HBr is liberated from the potassium bromide by means of concentrated sulphuric acid, constitutes a very smooth example of this reaction. 

Itaconic Acid. Structurally an a-substituted methacrylic acid, itaconic acid constitutes a C5 building block with significant market opportunities. It is currently produced via fungal fermentation at about 10,000 t/a and mainly used as a specialty comonomer in acrylic or methacrylic resins, as incorporation of small amounts of itaconic acid into polyacrylonitrile significantly improve their dyeability. 

Saw palmetto Serenoa repens) is a dwarf American palm native to the extreme southeastern United States. A lipidosterolic extract of its berries contains fatty acids (especially lauric acid), phytosterols, monocylglycerides, and polysaccharides. Fatty acids constitute more than 80% of the extract and are thought to be the most clinically effective component. It is widely used to treat benign prostatic hypertrophy (BPH). Tlie berries themselves are less well absorbed than the extract and are therefore believed to be less effective. 

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