the kinetics of the de complexation by hydroxyl ions of some pervanadyl, molybdate and tungstate amionocarboxylate complexes have been studied spectrophotometrically by means of a stopped flow technique. the chelate groups used were the iminodiacetic acid (ida), ethylenediarnine-n,n' -diacetic acid (edda), nitrilotriacetic acid (nta) and ethylene diamine-n,n,n' ,n'-tetraacetic ac...

The crystal structure of title compound, [Eu(NO(3))(3)(C(15)H(15)NO(2))(2)], contains two Schiff base 6-meth-oxy-2-[(4-methyl-phen-yl)imino-meth-yl]phenolate (L) ligands and three independent nitrate ions that chelate to the europium(III) ion via the O atoms. The coordination number of the Eu(III) ion is ten. The L ligands chelate with a strong Eu-O(deprotonated phenolate) bond and a weak Eu-O(...

An experiment was conducted to investigate the effects of dietary supplementation of copper chelates in the form of methionine, chitosan and yeast on the performance of laying hens. Four hundred ISA Brown layers, 84 wks old, were assigned to 4 treatments: control, 100 ppm Cu in methionine chelate (Met-Cu), 100 ppm Cu as chitosan chelate (Chitosan-Cu) and 100 ppm Cu as yeast chelate (Yeast-Cu). ...

Reduction of Fe(3+) to Fe(2+) is a prerequisite for Fe uptake by tomato roots. Ferric chelate reductase activity in plasma membranes (PM) isolated from roots of both iron-sufficient (+Fe) and iron-deficient (-Fe) tomatoes (Lycopersicon esculentum Mill.) was measured as NADH-dependent ferric citrate reductase and exhibited simple Michaelis-Menten kinetics for the substrates, NADH and Fe(3+)(citr...

The strawberry is a low-growing, herbaceous perennial plant, sensitive to iron deficiency. deficiency represents nutritional disorder, leading decreased content of photosynthetic pigments, which determines the yellow color characteristic chlorotic leaves. Therefore, in calcareous soils, use synthetic chelate often mandatory cultivation. employment novel microorganism-based formulations as alter...

HO (haem oxygenase) catalyses the degradation of haem to biliverdin, CO and ferrous iron via three successive oxygenation reactions, i.e. haem to alpha-hydroxyhaem, alpha-hydroxyhaem to alpha-verdohaem and alpha-verdohaem to ferric biliverdin-iron chelate. In the present study, we determined the crystal structure of ferrous alpha-verdohaem-rat HO-1 complex at 2.2 A (1 A=0.1 nm) resolution. The ...