Acid EDTA treatment

Harrison et extracted polymer from R. eutropha upon treatment with lytic enzymes of Cytophaga sp. without any mechanical processing and 90% purity was achieved by this method. Lu et al., 2006 developed a combined method involving enzyme and sodium hypochlorite for extraction of polymer from Burkholderia sp. PTU9. A recovery of 89% was achieved by this process. De Koning and Witholt reported a combined process involving sequential treatment with heat, alcalase, and SDS assisted by Ethylene Diamine Tetraacetic Acid (EDTA) treatment for the recovery of the polymer from Pseudomonas. A recovery rate of 95% was achieved by this process. 

Inorganic heavy metals are usually removed from aqueous waste streams by chemical precipitation in various forms (carbonates, hydroxides, sulfide) at different pH values. The solubiUty curves for various metal hydroxides, when they are present alone, are shown in Figure 7. The presence of other metals and complexing agents (ammonia, citric acid, EDTA, etc) strongly affects these solubiUty curves and requires careful evaluation to determine the residual concentration values after treatment (see Table 9) (38,39). 

The complexers maybe tartrate, ethylenediaminetetraacetic acid (EDTA), tetrakis(2-hydroxypropyl)ethylenediamine, nittilotriacetic acid (NTA), or some other strong chelate. Numerous proprietary stabilizers, eg, sulfur compounds, nitrogen heterocycles, and cyanides (qv) are used (2,44). These formulated baths differ ia deposition rate, ease of waste treatment, stabiHty, bath life, copper color and ductiHty, operating temperature, and component concentration. Most have been developed for specific processes all deposit nearly pure copper metal. 

Organic chelant compounds, such as the sodium salts of ethylenedi-aminetetraacetic acid (EDTA) and nitrilotriacetic acid (NTA) are commonly used in BW deposit control treatments, often in combination with phosphates. 

Clem and Hodgson [783] discuss the temporal release of traces of cadmium and lead in bay water from EDTA, ammonium pyrrolidine diethyldithiocarba-mate, humic acid, and tannic acid after treatment of the sample with ozone. Anodic scanning voltammetry was used to determine these elements. 

Formation of heterocyclic nitrones (151) from the corresponding amino oximes (150) has been observed upon treatment with Hg(II)-ethylenediaminetetraacetic acid (EDTA) (Scheme 2.54) (308, 309). 

The treatment of metal poisoning is to administer a compound that binds the metal ion more strongly than does the group in the active centre of the enzyme. These compounds are known as chelating agents. For lead, the compound ethyl-enediaminetetraacetic acid (EDTA) is used. For mercury, dimercaptopropanol (dimercaprol) is used. 

Imidazo[l,2-a]pyridine , imidazo[5,l-a]isoquinoline and imidazo[2,l-a]iso-quinoline rings were successfully obtained from pyridine or isoquinoline oximes or their ethers. Thus, oxime ethers 130 were converted to imidazopyridines 131 in the presence of EtsN in methanol (equation 57). Esoquinoline oxime 132 by treatment with ethylenediaminetetraacetic acid (EDTA)/HgO and then AC2O gave imidazoisoquinoline 133 (equation 58). Similar mercury(EE)/EDTA mediated cyclization of pyridine oximes afforded fused dihydroimidazoles... 

Chromium [10,39], niobium [42], titanium [13], and 90% titanium/10% tungsten [58] have been used as adhesion layers for platinum deposition. Chemical etching procedures based on H202/ethylenediamine tetraacetic acid (EDTA)/ NH4OH have been described for removal of interfering titanium [13] or tita-nium/tungsten [58] adhesion components from the surface of platinum electrodes. The procedure was shown to be effective for more than 24 h after treatment,... 

A common treatment for metal intoxication is the use of chelators. A chelator is a flexible molecule with two or more electronegative groups that can form stable complexes with cationic metal atoms. The complexes are then eliminated from the body. The most widely used chelator is eth-ylenediaminetetraacetic acid (EDTA). It has four binding positions (two nitrogen atoms and two oxygen atoms) that focus on the metal ion. It works very well on many metals, the most notable being calcium, magnesium, and lead, see also Enzymes Proteins Tertiary Structure Toxicity. 

In the work-up of the diethyl ether reaction, the solvent is removed (in a hood) under a stream of nitrogen. Then the ether-free aqueous dispersion is mixed with 10 ml of a 5 mM EDTA solution to bind the calcium ions. Without the latter treatment, the calcium salt of the phosphatidic acid cannot be recovered (easily) from the reaction mixture. Thus, subsequent to the EDTA treatment, the sample is mixed with sufficient chloroform and methanol to make a mixture of chloroform-methanol-water (1 2 0.8, v/v). Then 0.5 volume chloroform and 0.5 volume water are added, and the mixture is vigorously shaken for 1 min and then allowed to separate into two phases. The upper, water-rich phase contains free nitrogen base—in this case, choline. It can be analyzed by the techniques described earlier. 

Ouattara, L., Duo, I., Diaco, T., Ivandini, A., Honda, K., Rao, T., Fujishima, A. and Comninellis, Ch. (2003) Electrochemical oxidation of ethylenediaminetetraacetic acid (EDTA) on BDD electrodes Application to wastewater treatment. New Diam. Front. Carbon Technol. 13, 97-108. 

The biochemical reaction performed by the methyltransferase appears to be metal dependent, as determined by chemical inhibition studies, but the exact identity of this metal has yet to be defined [41]. EDTA treatment had no inhibitory effect on Stel4p, but incubation of the protein with 10 - 50 mM of the metal chelating agent 1,10-phenanthroline eliminated catalytic activity [37,41]. Additionally, even more hydrophobic metal sequesterants such as zincon [37], lysine nitriloacetic acid (Lys-NTA) [42], and cholesteryl-Lys-NTA [43] also inhibited the methyltransferase but at much lower concentrations. Together, these data suggest that the metal ion may be buried in a hydrophobic region of the enzyme. 

From the mere fact that CF, can be released from the membrane by EDTA treatment and the enzyme stays in solution without detergents, it is apparent that the catalytic sector has minimal, if any, direct interaction with the lipids of the chloroplast membrane. It is a globular protein that is held to the surface of the membrane via interaction with the membrane sector. Recently it was shown that the y subunit is in immediate contact with the membrane sector and the 8 and e subunits may induce proper binding for catalysis [17,18], The enzyme contains a few well-defined sites that were used for localization experiments by the method of fluorescent energy transfer [19,56-61], These studies revealed the position of those sites and helped to localize the various subunits of CF, in space relative to the chloroplast membranes (for a model of CF, see Refs. 61 and 62). These experiments are awaiting analysis of the amino acid sequence of the y subunit that is now under investigation in Herrmann s laboratory [148], Definite structural analysis could be obtained only after good crystals of the enzyme become available. 

Hydroxumie acids. Oxidation of N-trimethylsilylamtdes (I, prepared by the reaction of a secondary amide with hexamethyldisilazane) with the MoOvMMPT complex in methylene chloride at room temperature for several hours np to several days affords dioxomolybdenum complexes (2) in moderate yields (15-40%). The free hydroxamic acids (3) are Hbcrated by treatment of (2) with ethylenediaminetetraacetic acid (EDTA). 

The proteins of the cell envelope of Ps. aeruginosa have received somewhat less attention than the other components. Recently, it was found [17] that the envelope contains a wide variety of proteins. There do, however, appear to be three characteristic proteins, two of which are gylcoproteins and are found associated with the protein-lipopolysaccharide complex released on treatment of envelopes with ethylenediaminetetra-acetic acid (EDTA). This complex is part of the outer layer of the envelope [18]. 

A 34-year-old man developed swelhng and redness of the face after receiving lidocaine as Lignospan for dental treatment. Patch testing showed allergic contact dermatitis due to the preservative disodium ethylene-diamine tetra-acetic acid (EDTA). 

Advantages cited in more recent reports with the ascorbate treatment include reduced curing time (480,483,485,487,488) better, more stable, and more uniform color (480,482,483,485,489-495), less nitrite required or lower nitrite levels (480,482,496-500), better flavor, and less rancidity. To emphasize the importance of the ascorbic acid application in lowering the residual nitrite levels in cured meat, the data of Brown et al. (497) may be examined (Table XVII). Other additives to accompany the ascorbic acid treatment of meat have been suggested. Boren-stein and Smith (501, 502) reported the use of ethylenediaminetetraacetic acid (EDTA) or its salt (preferably Fe) in combination with ascorbate and with nitrite or nitric oxide to accelerate the formation of cured meat color. Other additives (503-506) cited with ascorbic acid were cysteine (505), glutamate (504), histidine (500), niacin, niacinamide (504,505, 506), phosphates (503), and succinate (504). 

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