Copper glutamate

Drinking water equivalent of 42.5 mg/kg BW daily as copper glutamate lifetime exposure... 

Method A A soln of sodium copper glutamate (0.8 g, 2 mmol) in H2O (4 mL) was added to DMF (4 mL) containing benzyl iodide (0.872 g, 4 mmol). The resulting suspension was stirred at 35-40 °C for 24 h and then diluted with acetone (10 mL). The crude y-benzyl glutamate copper complex was washed thor-... 

For the separation of amino acids, the applicability of this principle has been explored. For the separation of racemic phenylalanine, an amphiphilic amino acid derivative, 1-5-cholesteryl glutamate (14) has been used as a chiral co-surfactant in micelles of the nonionic surfactant Serdox NNP 10. Copper(II) ions are added for the formation of ternary complexes between phenylalanine and the amino acid cosurfactant. The basis for the separation is the difference in stability between the ternary complexes formed with d- or 1-phenylalanine, respectively. The basic principle of this process is shown in Fig. 5-17 [72]. 

R Ledger, FHC Stewart. The preparation of substituted y-benzyl L-glutamates and 13-benzyl L-aspartates. (copper(II)) Aust J Chem 18, 1477, 1965. 

Aspartic and glutamic acids were not retained in a buffer solution without a counter-ion however, these acids were retained by the addition of octyl sulfate to the eluent, as seen in Figure 4.12. These amino acids can form a complex with copper ions and will be retained on the stationary phase. The addition of both a counter-ion and copper ions further increased the retention and made possible... 

Figure 4.12 Effect of counter-ions and copper on the retention of amino acids. Column, octadecyl-bonded silica gel, 25 cm x 4.6 mm i.d. eluent, 0.01 M sodium acetate buffer (pH 5.6) containing 1.2 mM sodium octanesulfonate (Oc) andj or 0.1 mM copper acetate (Cu) flow rate, 1ml min-1 detection, UV 220 nm. Compounds Glu, glutamic acid, Asp, aspartic acid.

Aspartic Acid.—A portion of the aspartic acid, after separation from phenylalanine ester and after hydrolysis by baryta, may separate as barium salt this is the barium salt of racemic aspartic acid. The remainder is isolated, when the glutamic acid has been removed as hydrochloride, by boiling with lead hydroxide and treating with hydrogen sulphide to remove hydrochloric acid and lead respectively, and by crystallising from water. It maybe characterised by conversion into its copper salt, or by analysis, and is estimated by its weight. 

Neutral. A bis(ethylenediamine) structure has been incorporated into the surfactant molecule -Ci6H33C(H)[CON(H)(CH2)2NH2]2 in older to incorporate metal ions in an LB film structure via coordination instead of ionic complexation as occurs for anionic/cationic amphiphiles (14). Also, films of n-octadecylacetoacetate containing Cu2+ have been prepared, and exposure to H2S has resulted in the formation of a copper sulfide (39). Ditetradecyl-A-[4- [6-(A, N, W -trimethyl-ethylenediamino)-hexyl]oxy]benzoyl]-L-glutamate (DTG), which also contains the ethylenediamine unit, was used to make self-assembled films containing Cd2+ (40). 

These examples illustrate that biomolecules may act as catalysts in soils to alter the structure of organic contaminants. The exact nature of the reaction may be modified by interaction of the biocatalyst with soil colloids. It is also possible that the catalytic reaction requires a specific mineral-biomolecule combination. Mortland (1984) demonstrated that py ridoxal-5 -phosphate (PLP) catalyzes glutamic acid deamination at 20 °C in the presence of copper-substituted smectite. The proposed pathway for deamination involved formation ofa Schiff base between PLP and glutamic acid, followed by complexation with Cu2+ on the clay surface. Substituted Cu2+ stabilized the Schiff base by chelation of the carboxylate, imine nitrogen, and the phenolic oxygen. In this case, catalysis required combination of the biomolecule with a specific metal-substituted clay. 

The most persistent and stable amino acids appear to be glycine, aspartic acid, and glutamic acid, which were reported in Paleozoic anthracite from Great Britain by Heijhenskjold and Mollerberg (8). Among the most stable amino acid chelates are those formed with copper however, the stability constants for the a-amino acids of copper do not differ to the point where they indicate that the above mentioned three acids would be preferentially preserved. 

In the chelates of glycine, aspartic acid, and glutamic acid all the carbon and nitrogen atoms form part of the ring structure. This probably is the reason why these three acids appear to outlast all others in high rank coal. It should be pointed out that in the presence of hydrogen sulfide, copper is precipitated as the sulfide from copper-amino acid chelates. Thus, copper and perhaps other elements could be transported as amino acid chelates until sufficient hydrogen sulfide was encountered to cause precipitation. 

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