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Comparison of Dissolution and Surface Reactions Between Calcite and Aragonite in L-Glutamic and L-Aspartic Acid Solutions  [PDF]
Miyoung Ryu,Hwan Kim,Mihee Lim,Kwangsuk You,Jiwhan Ahn
Molecules , 2010, DOI: 10.3390/molecules15010258
Abstract: We have investigated dissolution and surface reaction of calcite and aragonite in amino acid solutions of L-glutamic (L-glu) and L-aspartic acid (L-asp) at weak acidity of above pH 3. The surface reactions of calcite and aragonite were related with the dissolution. Calcite was dissolved in both solutions but the dissolution was limited by an adsorption of Ca-carboxylate salt. Aragonite was neither dissolved nor reacted in amino acid solutions because the crystal surface consisted of a hard to dissolve structure.
Metal ion–binding properties of the L-aspartic acid and tartaric acid, a coparative investigation. How can be increased the dosage of mineral absorption in the body  [PDF]
Seyed Ali Akbar Sajadi
Advances in Bioscience and Biotechnology (ABB) , 2010, DOI: 10.4236/abb.2010.14047
Abstract: A comparative research has been developed for acidity and stability constants of M(TTA)1 and M(Asp)2 complexes which have been determined by potentiometric pH titration. Depending on metal ion–binding properties, vital differences in building complex were observed. The present study shows that in M(TTA) complexes, metal ions are coordinated to the carboxyl groups, but in M(Asp) some metal ions are able to build macrochelate over amine group. Hence, the following intermolecular and as a result independent concentration equilibrium between an open–isomer M(Asp)op and a closed–isomer M(Asp)cl, has to be considered cl op. The amounts are reported. The results mentioned above demonstrate that for some M(Asp) complexes the stability constants is also largely determined by the affinity of metal ions for amine group. This leads to a kind of selectivity of metal ions and transfer them via building complexes with the aspartate. The result of this effect is a higher dosage-absorption of minerals in body. Based on the sort of metal ions, the drug-therapy can be different. For heavy metal ions this building complex helps the absorption and filtration of the blood plasma, and consequently the excursion of heavy metal ions takes place. This is an important method in microdialysis. Other metal ions such as the complexes can be considered as mineral carriers. These complexes in certain conditions (PH–range) can release the minerals in body.
KINETICS AND MECHANISM OF OXIDATION OF L-ASPARTIC ACID BY POTASSIUM PERMANGANATE IN AQUEOUS ACID MEDIUM  [PDF]
J. S. DIGGIKAR
Golden Research Thoughts , 2013, DOI: 10.9780/22315063
Abstract: The oxidation of L-aspartic acid by potassium permanganate in aqueous perchloric acid medium has been studied. The reaction is first order dependence on potassium permanganate concentration and order in L-aspartic acid is fractional which suggests intermediate complex formation between L-aspartic acid and potassium permanganate. The thermodynamic parameters are reported. The rate was found to increase with increasing concentration of perchloric acid. Suitable mechanism is proposed and rate laws derived explain the results obtained.
l-Glutamic acid hydrochloride at 153 K  [cached]
Yi Jian Zhang,Zhan Shu,Wei Xu,Gang Chen
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536807068560
Abstract: The title compound [systematic name: (S)-1,3-dicarboxypropanaminium chloride], C5H10NO4+·Cl , has been investigated previously by Dawson [Acta Cryst. (1953). 6, 81–83], with R = 0.106 and without the location of H atoms, and then by Sequeira, Rajagopal & Chidambaram [Acta Cryst. (1972). B28, 2514–2519] using neutron diffraction with R = 0.043. The present determination at 153 K has R = 0.017 and all the H atoms are located. There are obvious differences in some C—C bond lengths between the present and previous studies. In the present structure, l-glutamic acid is protonated and is linked to the Cl anion by an O—H...Cl hydrogen bond. The crystal structure is established by a three-dimensional network of O—H...O, N—H...O and N—H...Cl hydrogen bonds.
Determination of L-aspartic acid by using the Cu(II)-catalyzed oscillating reaction
Gao, Jinzhang;Lv, Dongyu;Sun, Houtan;Yang, Wu;
Journal of the Brazilian Chemical Society , 2009, DOI: 10.1590/S0103-50532009001000009
Abstract: a convenient procedure by means of oscillating chemical system as an analytical tool to determine the l-aspartic acid (l-asp) is proposed. the system involves the cu(ii)-catalyzed reaction between hydrogen peroxide and sodium thiocyanate in an alkaline medium. the method relies on the linear relationship between the changes in the oscillation period and the logarithm of concentration of l-aspartic acid. optimized conditions were further validated to ensure the reliability of the method. under optimum conditions, the calibration plot is linearly proportional to the concentration of l-aspartic acid over the range from 1.17 × 10-5 mol l-1 to 7.10 × 10-8 mol l-1 with a corresponding regression coefficient of 0.9990 (rsd 2.75%). a lower limit of determination (lod) was 5.58 × 10-8 mol l-1. the proposed method has been used to determine l-aspartic acid in drug sample. additionally, the hplc technique was also used to confirm the determination results.
Response of Salt Stressed Ricinus communis L. To Exogenous Application of Glycerol and/or Aspartic Acid
Refaat M. Ali,Soad S. Elfeky,Hesham Abbas
Journal of Biological Sciences , 2008,
Abstract: Changes caused by salinity and glycerol or aspartic acid on growth, oil contents, endogenous glycerol and recinine alkaloids of Ricinus communis plant have been studied. Growth, oil contents and recinine alkaloids in roots of Ricinus communis plant were significantly lowered with the salinization effect using NaCl. On other hand, oil contents and recinine alkaloids in shoots were increased. However, endogenous glycerol in shoots and roots increased with increasing salinization level. Growth, oil contents, recinine alkaloids and endogenous glycerol in the different organs of plant originating from seeds soaked in glycerol or aspartic acid were generally increased over the control. However, recinine alkaloids in roots decreased. Soaking seeds in glycerol or aspartic acid counteracted the adverse effect of salinity on growth and secondary products of Ricinus communis L. Plant.
MODELING THE FERMENTATIVE PRODUCTION OF L-GLUTAMIC ACID BY CORYNEBACTERIUM GLUTAMICUM IN A BATCH BIOREACTOR  [PDF]
N. S. Khan,R.P. Singh,B. Prasad
International Journal of Engineering Science and Technology , 2013,
Abstract: The fermentation kinetics of L-glutamic acid by Corynebacterium glutamicum was studied in a batch bioreactor. Mathematical model using the logistic equation for growth, Leudeking-Piret kinetic equation for product formation and Leudeking-Piret like equation for substrate consumption was proposed. Based on the analysis of experimental data followed by computer simulation, the model seemed to provide a reasonable description for L-glutamic acid fermentation.
Comments on the paper: Optical reflectance, optical refractive index and optical conductivity measurements of nonlinear optics for L-aspartic acid nickel chloride single crystal  [PDF]
Bikshandarkoil R. Srinivasan,Suvidha G. Naik,Kiran T. Dhavskar
Physics , 2015, DOI: 10.1016/j.optcom.2015.10.047
Abstract: We argue that the L-aspartic acid nickel chloride crystal reported by the authors of the title paper (Optics Communications 2013) is actually the well-known diaqua(L-aspartato)nickel(II) hydrate crystal.
Synthesis and evaluation of L-glutamic acid analogs as potential anticancer agents  [cached]
Viswanathan C,Deb S,Jain A,Lokhande T
Indian Journal of Pharmaceutical Sciences , 2008,
Abstract: Four N-(benzenesulfonyl)-L-glutamic acid bis(p-substituted phenylhydrazides) were synthesized and evaluated for anticancer activity in vitro in DU-145 and PC-3 prostate cancer and in COLO-205 colon cancer cell lines by MTT assay. The analog with the nitro group substitution exhibited potent activity (% Inhibition 84.7 and 72.0 in DU-145 and PC-3 respectively at 80 mg/ml concentration). Another series of substituted 1-(benzenesulfonyl)-5-oxopyrrolidine 2-carboxamides (11a-f) were synthesized and evaluated for anticancer activity in vitro in colon (COLO-205), breast (Zr-75-1) and prostate (PC-3) cancer cell lines by MTT assay using adriamycin as standard. Test compounds 11a-c showed potent activity (% Inhibition 61.2 to 79.2 at 20 mg/ml and 67.2 to 87.2 at 40 mg/ml) in PC-3 cell line which is superior to the activity of Adriamycin. In comparison compounds 11d-f were less potent. In Zr-75-1 cell line 11a-e showed % inhibition ranging from 32.4 to 54.9 at 10 mg/ml concentration while in COLO-205 cell line 11a-f showed poor activity.
The Metal Ions Absorption – and Transportation Properties of L-Aspartic Acid in the Body
S. Ali A. Sajadi and Ali A. Alamolhodavia
The Open Conference Proceedings Journal , 2010, DOI: 10.2174/2210289201001010207]
Abstract: The intra molecular interactions in complexes of Aspartic acid with divalent metal ions (Mg, Ca & Zn) M(Asp)1 were investigated in this work. The acidity constants of Asp and stability constants of M(Asp) are determined and reported as well. The effect of intra molecular interactions can be seen by comparison of these stability constants. Mg and Ca ions form weaker bonds to Asp than Zn ion. Zn(Asp) complex undergoes an intra molecular interaction and builds a chelate in two forms ( an open – isomer M(Asp)op and a closed – isomer M(Asp)cl ). The concentration independent intra molecular interaction constant for two isomers has been calculated and reported. The obtained results demonstrate that for some M(Asp) complexes the stability constant is largely affected by the affinity of metal ions for amine group. This shows a kind of selectivity of metal ions and transfer them via complex – building with the aspartate. Also all three metal ions complexes could be considered as mineral carriers. These complexes can release the minerals in human body in certain conditions ( e,g. pH – range).
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