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Alanine - Valine dynamics in pregnant rabbits
TS Emudianughe, B Kalderon, A Lapidot
African Journal of Biomedical Research , 2003,
Abstract: [15N]-alanine and [15N]–valine dynamics were studied in 29 -30 days pregnant New-Zealand rabbits. Over the experimental period, there was no detectable significant difference of mean ± SD of alanine concentrations within the sampling intervals in maternal, umbilical venous and arterial blood samples suggesting that alanine concentration was in a steady state and that the system was not being perturbed. Similar results were obtained for valine. The enrichment of alanine in the umbilical venous blood was 68.9 ± 2.4% lower than that simultaneously obtained from the maternal vein (P < 0.05). A decrease of 42.7 ± 4.7% in the umbilical arterial sample was observed compared to umbilical venous blood. The data suggest possible fetus production of alanine in utero. Both the maternal and foetal compartment were in isotopic steady state. Comparison of the enrichment of valine in the umbilical venous blood was 54.8 ±6.3% less than that of the maternal blood. Statistical comparison of the umbilical venous and arterial showed no significant difference. This suggests that there was no apparent valine production during the experimental period.
Determination of enantiomeric excess of leucine and valine by X-ray powder diffraction  [cached]
El?bieta Tadeusiak,Rafal Kruszynski,Agata Trzesowska-Kruszynska,Tomasz Sieranski
European Journal of Chemistry , 2010, DOI: 10.5155/eurjchem.1.4.319-321.224
Abstract: Two amino acids, leucine and valine, were studied by X-ray powder diffraction (XRPD). The linear correlations between intensity of racemate (decrease) or enantiomer (increase) and enantiomeric excesses were observed in each case.
Effects of Valine and Leucine on Some Antioxidant Enzymes in Hypercholesterolemic Rats  [PDF]
Elena Cojocaru, Nina Filip, Carmen Ungureanu, Cristiana Filip, Mihai Danciu
Health (Health) , 2014, DOI: 10.4236/health.2014.617266
Abstract: Objective: Reactive oxygen species (ROS) are involved in the endothelial-mediated disorders within atherosclerosis. Considering that an oxidant/antioxidant imbalance might be a key factor in the damaging ROS-mediated effects, the present study intends to determine the influence of a high-fat diet, associated with essential amino acids—valine and leucine, upon the experimental animals, through evaluation of plasmatic level of some antioxidant enzymes. Material and Methods: The study was conducted on 32 male Wistar rats, which were fed with cholesterol, valine and leucine, for 60 days. The animals were divided into four groups, according to the received diet: the first group—standard diet; the second group—cholesterol (C); the third group—cholesterol and valine (C + V); the fourth group—cholesterol and leucine (C + L). Evaluations of the oxidative status, through plasma levels of the antioxidant enzymes: superoxide dismutase (SOD) and glutathione peroxidise (GPx), were made for the four mentioned groups of animals, at the beginning of the study (R0), after one (R1) and two months (R2). Results: The average values of SOD and GPx in group of animals fed exclusively with cholesterol (C) were significantly higher compared to the third group where cholesterol was supplemented with valine (C + V) or fourth group fed with cholesterol and leucine (C + L) (p < 0.001), after one month as well at the end of the experiment (two months). There were no significant differences in the levels of SOD and GPx between group III and group IV (p < 0.05) at the end of the experiment. Conclusion: Our results showed that valine and leucine decreased the serum levels of SOD and GPx and therefore they were useful antioxidants, which could improve the endothelial dysfunctions associated with atherosclerosis. Moreover, analysis of the oxidative status in the context of atherosclerotic mediated endothelial damage suggests that deviation from normal to alter endothelial status may be conditioned by an oxidants/antioxidants imbalance.
Colorimetry method for estimation of glycine, alanine and isoleucine  [cached]
Shah S,Rathod I,Kanakia Dharitri
Indian Journal of Pharmaceutical Sciences , 2007,
Abstract: A simple and sensitive colorimetry method has been developed for estimation of amino acids glycine, alanine and isoleucine. Amino acids were derivatized with dichlone in presence of sodium bicarbonate. Amino acids showed maximum absorbance at 470 nm. The method was validated in terms of linearity (5-25 μg/ml for glycine, alanine and isoleucine), precision (intra-day variation 0.13-0.78, 0.22-1.29, 0.58-2.52% and inter-day variation 0.52-2.49, 0.43-3.12, 0.58- 4.48% for glycine, alanine and isoleucine respectively), accuracy (91.43-98.86, 96.26-105.99 and 95.73-104.82 for glycine, alanine and isoleucine respectively), limit of detection (0.6, 1 and 1 μg/ml for glycine, alanine and isoleucine respectively) and limit of quantification (5 μg/ml for glycine, alanine and isoleucine). The method was found to be simple and sensitive.
Volumetric, viscometric and refractive index behaviour of amino acids in aqueous glycerol at different temperatures
A. ALI,S. KHAN,F. NABI
Journal of the Serbian Chemical Society , 2007,
Abstract: Densities, ρ, viscosities, η, and refractive indices, nD, of solutions of some amino acids (glycine, DL–alanine, DL–α–amino–n–butyric acid, L valine and L leucine) in the concentration range 0.02 to 0.10 m in 5 % (v/v) aqueous glycerol were determined at 298.15, 303.15, 308.15 and 313.15 K. These experimental data were used to calculate the apparent molar volumes, Φν, the infinite dilution apparent molar volumes, Φν0, the partial molar volumes of transfer, Φν0 (tr), of the amino acids from aqueous to aqueous glycerol solution, as well as the viscosity A and B coefficients of the Jones–Dole equation of the amino acids. The free energies of activation of viscous flow, Δμ10# and Δμ20# per mole of solvent and solute, respectively, were obtained by application of the transition–state theory to the B coefficient data and the corresponding activation enthalpy, ΔH*, and entropy, ΔS*, were also determined. The Φν0, B coefficients and Δμ20# were found to vary linearly with increasing number of carbon atoms in the alkyl chain of the amino acids, and they were split into contributions from the zwitterionic end groups (NH3+, COO-) and methylene (CH2) groups of the amino acids. The experimental values of the refractive indices, nD, were used to calculate the molar refractive indices, RD, of the amino acids + aqueous glycerol ternary mixtures. The results were interpreted in the light of the solute–solvent and solute–solute interactions in the mixed solvents.
Calculation and Comparison of Energy Interaction and Intensity Parameters for the Interaction of Nd(III) with DL-Valine, DL-Alanine and -Alanine in Presence and Absence of / in Aqueous and Different Aquated Organic Solvents Using 4f-4f Transition Spectra as Probe  [PDF]
H. Debecca Devi,Ch. Sumitra,Th. David Singh,N. Yaiphaba,N. Mohondas Singh,N. Rajmuhon Singh
International Journal of Spectroscopy , 2009, DOI: 10.1155/2009/784305
Abstract: Absorption difference and comparative absorption spectrophotometric studies involving 4f-4f transitions of Nd(III) and different amino acids: DL-valine, DL-alanine, and -alanine in presence and absence of Ca(II) and Zn(II) in aqueous and different aquated organic solvents have been carried out. Variations in the spectral energy parameters: Slater-Condon (FK) factor, Racah (EK), Lande factor (4f), nephelauxetic ratio (), bonding (b1/2), percentage covalency () are calculated to explore the mode of interaction of Nd(III) with different amino acids: DL-valine, DL-alanine, and -alanine. The values of experimentally calculated oscillator strength (P) and computed values of Judd-Ofelt electric dipole intensity parameters, T ( = 2,4,6), are also determined for different 4f-4f transitions. The variation in the values of P and T parameters explicitly shows the relative sensitivities of the 4f-4f transitions as well as the specific correlation between relative intensities, ligand structures, and nature of Nd(III)-ligand interaction.
Synthesis and characterization of new polyamides derived from alanine and valine derivatives
Ayman El-Faham, Hammed HAM Hassan, Sherine N Khattab
Chemistry Central Journal , 2012, DOI: 10.1186/1752-153x-6-128
Abstract: Here we describe another family of polyamides based on benzene dicarboxylic acid, pyridine dicarboxylic acid, and α-amino acid linked to benzidine and 4,4′-oxydianiline to study the effect of the dicarboxylic acid as well as the amino acids on the nature and thermal stability of the polymers.We report here the preparation of a new type of polyamides based on benzene dicarboxylic acid, pyridine dicarboxylic acid, and α-amino acid linked to benzidine and 4,4′-oxydianiline to study the effect of the dicarboxylic acid as well as the amino acids on the nature and thermal stability of polymers. The thermal properties of the polymers were evaluated by different techniques. Results revealed that structure-thermal property correlation based on changing the dicarboxylic acid monomer or the diamine monomer demonstrated an interesting connection between a single change (changing the dicarboxylic acids in each series while the diamine is fixed) and thermal properties. The newly prepared polymers may possess biodegradability and thus may find some applications as novel biomaterials.The thermal properties of the new type of polyamides based on benzene dicarboxylic acid, pyridine dicarboxylic acid, and α-amino acid (alanine and valine) linked to benzidine and 4,4′-oxydianiline were evaluated by thermal gravimetric (TG), differential thermal gravimetric (DTG) and differential thermal analysis (DTA) techniques. Results revealed that the structure-thermal property correlation based on changing the dicarboxylic acid monomer or the diamine monomer demonstrated an interesting connection between a single change (changing the dicarboxylic acids in each series while the diamine is fixed) and thermal properties. In addition, pyridine-containing polymers exhibited semicrystalline characteristic with melting temperature, Tm. where none of the valine-containing polymers showed a melting and crystallization peak indicating that the polymers were amorphous. This is expected since L-valine side ch
Kinetics and Mechanism of Oxidation of Leucine and Alanine by Ag(III) Complex in Alkaline Medium
Changying Song,Lei Chen,Jinhuan Shan
International Journal of Inorganic Chemistry , 2008, DOI: 10.1155/2008/786857
Abstract: Kinetics and mechanism of oxidation of leucine and alanine by Ag(III) complex were studied spectrophotometrically in alkaline medium at constant ion strength. The reaction was in first order with respect to Ag(III) complex and amino acids (leucine, alanine). The second-order rate constant, ?, decreased with the increasing in [OH?] and [IO4?]. A plausible mechanism was proposed from the kinetics study, and the rate equations derived from mechanism can explain all experimental phenomena. The activation parameters were calculated at 298.2 K.
Effect of Hydroxylamine Sulfate on Volumetric Behavior of Glycine, L-Alanine, and L-Arginine in Aqueous Solution  [PDF]
Jie Chen,Sheng Fang,Yu-Gang Shi,Yue-Cheng Meng,Da-Hai Ren
Journal of Chemistry , 2013, DOI: 10.1155/2013/481341
Abstract: The apparent molar volumes of glycine, L-alanine, and L-arginine in aqueous hydroxylamine sulfate solutions have been determined at ?K and atmospheric pressure. The standard partial molar volumes, , corresponding partial molar volumes of transfer, , and hydration numbers, , have been calculated for these α-amino acids from the experimental data. The values are positive for glycine, L-alanine, and L-arginine and are all increased with the increase in the concentration of hydroxylamine ions. These parameters obtained from the volumetric data are interpreted in terms of various mixing effects between amino acids and hydroxylamine sulfate in aqueous solutions. 1. Introduction In recent years, the denaturation and renaturation behavior of biological molecules such as proteins in aqueous solutions has been the subject of extensive investigation [1–3]. However, the complex configurational and conformational factors affecting the structure of protein in aqueous solutions make the direct interpretation from studies on proteins very difficult [4]. Volumetric and transport properties of amino acids such as density and viscosity have been extensively investigated and can provide valuable information for conformational stability and unfolding behavior of globular proteins in aqueous solutions [5–13]. It is well recognized that inorganic and organic salts can produce remarkable effects on the conformation and properties of proteins in aqueous solutions. Hydroxylamine derivatives are always used by biologists for their ability to introduce random mutations by switching different base pairs [14]. Hydroxylamine can also be applied to selectively cleave peptide bonds in peptides and proteins [15]. The highly biological activities of hydroxylamine derivatives make it quite interesting to study the behaviour of proteins in the presence of hydroxylamine salts [16]. Consequently, the knowledge of thermophysical and thermodynamic properties of hydroxylamine with small molecules will be required and useful for obtaining information about various interactions occurring in aqueous hydroxylamine solutions with macromolecules. In this study, we present experimental densities of glycine, L-alanine, and L-arginine in aqueous and aqueous hydroxylamine sulfate solutions of (0.10, 0.25, and 0.40) mol?kg?1 at ?K and atmospheric pressure. From these data, the standard partial molar volumes ( ), standard partial molar volumes of transfer ( ), and molar hydration number ( ) have been calculated. The results are discussed in terms of various solute-solute interactions and also their nature
Interaction of Ingested Leucine with Glycine on Insulin and Glucose Concentrations  [PDF]
Jennifer F. Iverson,Mary C. Gannon,Frank Q. Nuttall
Journal of Amino Acids , 2014, DOI: 10.1155/2014/521941
Abstract: The majority of individual amino acids increase insulin and attenuate the plasma glucose response when ingested with glucose. Objective. To determine whether ingestion of two amino acids simultaneously, with glucose, would result in an additive effect. Leucine (Leu) and glycine (Gly) were chosen because they were two of the most potent glucose-lowering amino acids when given individually. Materials and Methods. Nine subjects received test items on four separate days. The first was a water control, then 25?g glucose, or Leu + Gly (1?mmol/kg fat-free mass each) ±25?g glucose, in random order. Glucose, insulin, and glucagon were measured frequently for 2.5 hours. Net areas were calculated. Results. The glucose area response decreased by 66%. The insulin area response increased by 24% after ingestion of Leu + Gly + glucose compared to ingestion of glucose alone. The decrease in glucose response was not additive; the increase in insulin response was far less than additive when compared to previously published individual amino acid results. The glucagon concentration remained unchanged. Conclusion. There is an interaction between Leu and Gly that results in a markedly attenuated glucose response. This occurred with a very modest increase in insulin response. Changes in glucagon response could not explain the results. The mechanism is unknown. 1. Introduction In a series of studies our laboratory has demonstrated that single amino acids when ingested at 1.0?mmol/kg fat free mass with or without 25?g of glucose stimulate a rise in insulin and glucagon. When ingested with glucose they are capable of attenuating the glucose rise integrated over a 2.5-hour period of time. Sixteen amino acids were studied. The potency of the individual amino acids in regard to their effect on the insulin, glucagon, and glucose concentrations varied greatly between amino acids and the specific responses could not be predicted based on the structure of the amino acids [1]. Leucine is well recognized to strongly stimulate insulin secretion and to reduce the glucose rise when ingested with glucose [2]. When ingested with glucose, glycine similarly reduced the glucose rise, but only weakly stimulated insulin secretion. [2, 3]. Therefore, we were interested in determining if the glucose-attenuating effect would be greater if these two amino acids were ingested together with glucose. We were particularly interested in whether the effects would be additive since glycine produced a major decrease in glucose response in the presence of only a very modest increase in insulin; that is, it may
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