Organic acids citric acid

Organic acids Citric acid Aspergillus niger Effervescent products sodium citrate used as an anticoagulant potassium citrate used to treat cystitis... 

Starch Amy lose Amylopectin Proteins Organic acids Citric acid Malic acid Succinic acid Fumaric acid Minerals... 

Organic acids Citric acid A. niger Y. lypolitica [253, 254]... 

Organic acids Citric acid, etc. Size distribution for separation... 

Organic acids Citric acid Aspergillus niger Cane, beet pulp mol. imprg. [9]... 

Because of these disadvantages, baking soda is disappearing from medicines. It is still used in effervescent tablets combined with some sohd organic acid (citric acid or tartaric acid), which form carbon dioxide bubbles with baking soda. 

Kakihana, in press). The minimum chelating skeleton is carboxylic acid with a hydroxy group attached to the alpha-carbon. Either multifunctional organic acid (citric acid) or several molecules of simple carboxylic acid create steric difficulties for the nucleophilic attack the first step of hydrolysis. The peroxo group occupies the available free position in... 

Gibberlic acid Mycotoxins Penicillin Surfactin Tetracyclines Zearalenone Organic acids Citric acid /-Linolenic acid Mycophenolic acid Gluconic acid... 

The BZ reaction involves the oxidation of an organic molecule (citric acid, malonic acid (MA)) by an... 

These acids are found ready-made in nature in great numbers. Some of them occur as free acids (citric acid, tannic acid, malic acid), others as esters (products of acids and alcohols, such as fats and oils and the flavors of many fruits and the odors of many flowers). Still other of these organic acids are produced by the action of bacteria (acetic acid from wine or cider, lactic acid when milk turns sour, butyric acid in rancid hutter). 

In most living organisms, the citric acid cycle constitutes the final common pathway in the degradation of foodstuffs anil cell constituents to carbon dioxide and water. This cycle is described In the entry-on Carbohydrates. 

Also present in many natural waters are humic/fulvic acid, citric acid, and the like. These organics also can complex actinides. In Figure 15.18, we show the relative stability constants for the first complexation reaction of various ligands with actinides of different oxidation states. Clearly, the carbonate and humate ions along with hydrolysis dominate the chemistry. The tetravalent actinide ions will tend toward hydrolysis reactions or carbonate complexation rather than humate/fulvate formation. 

Prior to high-performance liquid chromatography (HPFC), samples were filtered through a 0.2-gm pore size mixed cellulose ester filter (Schleicher Schuell, Dassel, Germany). Buffer components such as acetic acid, citric acid, maleic acid, and succinic acid were separated on an Aminex HPX-87H (Bio-Rad, Hercules, CA) organic acid column at 65°C using a... 

The precipitation of aluminium hydroxide by solutions of sodium hydroxide and ammonia does not take place in the presence of tartaric acid, citric acid, sulphosalicylic acid, malic acid, sugars, and other organic hydroxy compounds, because of the formation of soluble complex salts. These organic substances must therefore be decomposed by gentle ignition or by evaporating with concentrated sulphuric or nitric acid before aluminium can be precipitated in the ordinary course of qualitative analysis. 

In addition to the stable compounds mentioned below, the dl Crv ion is readily detected by esr spectroscopy as a transient species in the reduction of CrVI, as well as in certain oxide lattices and catalysts. The reduction of Crvl by oxalic acid, citric acid, isopropanol, and various other organic reductants gives esr-detectable Crv... 

S.J. Barnes and P.D. Weitzman. 1986. Organization of citric acid cycle enzymes into a multienzyme dusX t FEBS Lett. 201 267-270. (PubMed)... 

The acidity for the effervescent reaction can be obtained from three main sources acids, acid anhydrides, and acid salts. Traditional sources of acid materials are the organic acids, citric and tartaric acid however, some acid salts also are used. 

Many plants contain a variety of free acids such as acetic acid, citric acid, fumaric acid, malic acid, succinic acid, oxalic acid, glycohc acid, etc. They are components of citric cycle, whereas the others are intermediates in the pathway from carbohydrates to aromatic com-pounds. Following extraction, organic acids can be separated and detected with a variety of techniques. Thin layer chromatographic methods have been also employed to separate certain organic acids,as presented in Table 3. 

Examples of organic acids (citric, lactic, gluconic) produced by microorganisms, together with pharmaceutical and medical uses, are depicted in Table 25.2. Citric and lactic acids also have widespread... 

It is well known that organic complex-formers, such as simple organic acids (citric, oxalic, tartaric, salicyclic) formed by microorganisms in soils and humic or fulvic acids, solubilize mineral iron(III) and aluminum. These complex-formers not only increase the solubility of these minerals but also are able to form chelates on hydrous oxide surfaces and thus, in turn, catalyze the dissolution of oxides and aluminum silicates (Kummert and Stumm, 1980 Sigg and Stumm, 1980). The downward vertical displacement of A1 and Fe, as it is observed in the podsolization of soils, can be accounted for by considering the effect of pH and of complex formers on both solubility equilibria and dissolution rates (Schnoor and Stumm, 1985 Schnoor and Stumm, 1986). 

Organic acids (citric, lactic, acetic) Bacteria (both gram negative and gram positive) 2-3 70-1500 ppm 1-5 Often need mineral acid to lower pH active agent is nonionized form... 

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