scholarly journals STUDIES USING HPLC-PDA IN GABAPENTIN N-DERIVATIZATION REACTIONS WITH 9-FLUORENYLMETHYL CHLOROFORMATE (FMOC-CL)

Química Nova ◽  
2021 ◽  
Author(s):  
Emanoel Hottes ◽  
Carla Santos ◽  
Heloisa Souza ◽  
Marco Lima ◽  
Rosane Castro
Keyword(s):  
Amino Acids ◽  
Reaction Medium ◽  
Fluorescence Analysis ◽  
Basic Medium ◽  
Basic Reaction ◽  
Derivatizing Agent ◽  
Degradation Reaction

FMOC-Cl is a derivatizing agent widely used both in N-protection reactions of a-amino acids as well as in quantification and detection of amino acids and related molecules using HPLC-PDA or fluorescence analysis. In this work we studied the reaction of FMOC-Cl with gabapentin. However, it was observed that the degradation of gabapentin-N-FMOC and FMOC-Cl to FMOC-OH occur simultaneously in presence of the basic reaction medium which is specific for gabapentin derivatization. The degradation reaction is accelerated in temperatures above 45 °C and also by the time of contact of the reactant and product with basic medium. In this study, gabapentin derivatization reactions were shown to be cleaner and more efficient when an FMOC-Cl/gabapentin ratio of 2:1 was used, at 25 °C over a period of 15 minutes.

Structural and Functional State of Erythrocyte Membranes at Drug Addiction

2021 ◽  
Vol 18 (1) ◽  
pp. 13-19
Author(s):  
A.I. Rabadanova ◽  
Keyword(s):  
Amino Acids ◽  
Drug Addiction ◽  
Functional State ◽  
Conformational Changes ◽  
Structural Integrity ◽  
Fluorescence Analysis ◽  
Heroin Addiction ◽  
Dimensional Structure ◽  
Erythrocyte Membranes ◽  
Drug Addicts

The steady growth in the number of drug addicts, especially among young people, dictates the need to find ways to prevent and treat this disease. In this regard, there is a need for a more detailed study of the mechanisms of the course of this disease using modern research methods, such as atomic force microscopy and fluorescence analysis of amino acid residues. Purpose of the work: to reveal the structural and functional state of erythrocyte membranes in drug addiction. Materials and methods. The studies were carried out on the erythrocyte membranes of 60 subjects suffering from heroin addiction. The shape and topography of the erythrocyte surface were studied, and spectral analysis of the proteins of the erythrocyte membranes was carried out. Results. The conducted AFM studies of erythrocyte membranes indicate the heterogeneity of the surface mechanical properties of the erythrocyte membranes of drug addicts. The data obtained indicate an acceleration of the aging process of erythrocytes in drug addiction, which goes in two ways: the formation of outgrowths on the plasmolemma, which subsequently die off (echinocytes) and invagination of the plasmolemma of erythrocytes (spherocytes). The fluorescence spectrum of amino acids in erythrocytes of drug addicts is characterized by a significant decrease in the intensity of almost all peaks and a shift of the fluorescence peak to the short-wave region. Findings. With drug addiction, changes in the structural integrity of red blood cells are noted. In people with drug addiction, in comparison with healthy people, there is a higher variability of the morphology of erythrocytes, which is expressed in a significant increase in the proportion of echinocytes and spherocytes against the background of a significant decrease in the number of discocytes. For the membrane proteins of erythrocytes of drug addicts, conformational changes are characteristic, manifested in a decrease in the intensity of fluorescence of aromatic amino acids, which indicates their structural modification and significant vulnerability of the hematopoietic system. They are largely determined by changes in the fluorescence intensity of tryptophan and, to a lesser extent, tyrosine, which indicates the preservation of the three-dimensional structure of the protein.

scholarly journals The effect of the nitrogen source type on the growth and consumption of crude glycerol by Streptomyces hygroscopicus CH-7

2021 ◽  
Vol 10 (1) ◽  
pp. 41-45
Author(s):  
Slavica Ilić ◽  
Jovan Ćirić ◽  
Gordana Gojgić-Cvijović
Keyword(s):  
Amino Acids ◽  
Sunflower Oil ◽  
Crude Glycerol ◽  
Biomass Concentration ◽  
Nitrogen Sources ◽  
Biodiesel Production ◽  
Streptomyces Hygroscopicus ◽  
Basic Medium ◽  
Source Type ◽  
Glycerol Consumption

In this paper we studied the effect of different amino acids (arginine, tryptophan, tyrosine, and phenylalanine) as nitrogen sources on the growth of actinomycete Streptomyces hygroscopicus CH-7 and the consumption of crude glycerol, obtained as a by-product in the biodiesel production from sunflower oil. The highest biomass concentration (9.5 g/L) was achieved using the basic medium and the medium with tryptophan (9.2 g/L), while the crude glycerol consumption was the highest in the basic medium (5.9 mg/mL) and the medium with phenylalanine (3.3 mg/mL).

scholarly journals Synthesis, Structural, and Antimicrobial Studies of Some New Coordination Compounds of Palladium(II) with Azomethines Derived from Amino Acids

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Monika Gupta ◽  
Sangeeta Sihag ◽  
A. K. Varshney ◽  
S. Varshney
Keyword(s):  
Amino Acids ◽  
Coordination Compounds ◽  
Reaction Medium ◽  
Molar Ratio ◽  
Spectral Studies ◽  
Antimicrobial Studies ◽  
Elemental Analyses ◽  
C Nmr ◽  
Insecticidal Activities

Some new coordination compounds of palladium(II) have been synthesized by the reaction of palladium(II) acetate with azomethines in a 1 : 2 molar ratio using acetonitrile as a reaction medium. Azomethines used in these studies have been prepared by the condensation of 2-acetyl fluorene and 4-acetyl biphenyl with glycine, alanine, valine, and leucine in methanol. An attempt has been made to probe their bonding and structures on the basis of elemental analyses and IR,1H, and13C NMR spectral studies. Pd(II) compounds have been found to be more active than their uncomplexed ligands as both of them were screened for antibacterial, antifungal, and insecticidal activities.

Analysis of 26 amino acids in human plasma by HPLC using AQC as derivatizing agent and its application in metabolic laboratory

Amino Acids ◽  
2014 ◽  
Vol 46 (5) ◽  
pp. 1253-1263 ◽  
Author(s):  
Gaurav Sharma ◽  
Savita Verma Attri ◽  
Bijaylaxmi Behra ◽  
Swapnil Bhisikar ◽  
Praveen Kumar ◽  
...  
Keyword(s):  
Amino Acids ◽  
Human Plasma ◽  
Derivatizing Agent

STUDIES ON ASCOCHYTA IMPERFECTA PECK. DIFFERENTIAL UTILIZATION OF NUTRIENTS BY ISOLATES FROM CANADIAN ALFALFA SEED

1961 ◽  
Vol 39 (7) ◽  
pp. 1591-1594 ◽  
Author(s):  
H. W. Mead
Keyword(s):  
Amino Acids ◽  
Nitrogen Sources ◽  
Basic Medium ◽  
Alfalfa Seed

Isolates of Ascochyta imperfecta which had reacted differentially to 10 leguminous hosts were grown on a basic medium amended with various sugars, amino acids, and nitrogen sources. Significant differences in the yield of mycelium on the various media showed that these isolates responded specifically to different sugars and amino acids. Among the latter, cystine at 0.025% was inhibitory to all isolates. The significance of changes in the host on development of the fungus is discussed.

scholarly journals Functioned catalysts with magnetic core applied in the ibuprofen degradation

2021 ◽  
Author(s):  
Giane Gonçalves Lenzi ◽  
Mylena Ferreira Lopes ◽  
Dana Isabelly Andrade ◽  
José Salvador Napoli ◽  
Andrieli Parolin ◽  
...  
Keyword(s):  
Photocatalytic Degradation ◽  
Magnetic Separation ◽  
Reaction Medium ◽  
Solution Concentration ◽  
Magnetic Core ◽  
Organic Additive ◽  
Operation Conditions ◽  
The Matrix ◽  
Degradation Reaction ◽  
Activity Loss

Abstract In the present work, the performance of Ag/ZnO/CoFe2O4 magnetic photocatalysts in the photocatalytic degradation of Ibuprofen (IBP) was evaluated. This study considered the use of pure Ag/ZnO (5% Ag) and also use the Ag/ZnO/CoFe2O4 magnetic catalysts containing different amounts (5, 10 and 15% wt) of cobalt ferrite (CoFe2O4). The catalysts were characterized by Scanning Electron Microscopy (SEM), X-ray diffraction (XRD) and photoacoustic Spectroscopy. To carried the photocatalytic degradation reaction, different concentrations of the ibuprofen contaminant solution (10, 20 and 30 ppm) and different concentrations of photocatalyst were tested (0.3 gL−1, 0.5 gL−1 and 1.0 gL−1). The reaction parameters studied were: IBP concentration, catalyst concentration, adsorption and photolysis, influence of the matrix, radiation source (solar and artificial) and the effect of organic additive. At the end of the photocatalytic tests, the best operation conditions were defined. Considering the obtained results of degradation efficiency and magnetic separation, the optimal parameters selected to proceed with the other tests of the study were: ibuprofen solution concentration 10 ppm, Ag/ZnO/CoFe2O4(5%) catalyst at a concentration of 0.3 g L−1 and pH 4.5 of the reaction medium. The results indicated the feasibility of magnetic separation of the synthesized catalysts. A long duration test indicated that the catalyst exhibits stability throughout the degradation reaction, as more than 80% of ibuprofen was degraded after 300 minutes. The photocatalytic activity was directly affected by the ferrite load. The higher the nominal load of ferrite, the lower the performance in ibuprofen degrading. It was also observed that the smallest amount of ferrite studied was enough for the catalyst to be recovered and reused. The adsorption and photolysis tests did not show significant results in the IBP degradation. In addition, it was possible to verify that the aqueous matrix, the use of solar radiation and the addition of additive (acid formic) interfered direct in the process. The catalyst reuse tests indicated that it can be recovered and reused at least three times without considerable catalytic activity loss.

scholarly journals Keratin Hydrolysates Extracted from Sheep Wool with Potential Use as Organic Fertilizer

2020 ◽  
Vol 20 (3) ◽  
pp. 267-276
Author(s):  
Mariana Daniela Berechet ◽  
Demetra Simion ◽  
Maria Stanca ◽  
Cosmin-Andrei Alexe ◽  
Ciprian Chelaru ◽  
...  
Keyword(s):  
Amino Acids ◽  
Particle Size ◽  
Organic Fertilizer ◽  
Control Sample ◽  
Reaction Medium ◽  
Organic Fertilizers ◽  
Particle Measurements ◽  
Potential Use ◽  
Wheat Seeds ◽  
Sheep Wool

Keratin hydrolysates were obtained from sheep wool by alkaline hydrolysis at different concentrations of KOH (3%, 5% and 8%) and temperatures (75°C, 85°C, 95°C and 99°C) of the reaction medium. The protein content of the keratin extracts was between 65.54% and 87.10%. Particle measurements showed a decrease in particle size with the increase of concentration and temperature of the reaction medium. The ATR-FTIR spectra revealed specific bands to proteins and sulfur originated from keratin amino acids. The keratin hydrolysate type KerK895 was further investigated as organic fertilizer for two types of wheat seeds. The results showed that the use of 5% KerK895 led to the increase of the wheat stems lengths by 10.7% for Mirastar wheat and 18.3% for Tamino wheat, respectively, compared to control sample. Keratin hydrolysates are promising biopolymers as organic fertilizers in agriculture applications.

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