Biological activities of hy drazone derivatives

Human urine gives evidence of the metabolism in the body and contains different metabolites at various concentrations. A number of analytical techniques including mass spectrometry (MS) and nuclear magnetic resonance (NMR) have been used to obtain metabolites levels in urine samples. However, gas chromatography–mass spectrometry (GC–MS) is one of the most widely used techniques for urinary metabolomics studies due to its higher sensitivity, resolution, reproducibility, reliability, relatively low cost and ease of operation compared to liquid chromatography–mass spectrometry and NMR. This review looks at various aspects of urine preparation prior to analysis by GC–MS including sample storage, urease pretreatment, derivatization, use of internal standard and quality control samples for data correction. In addition, most common types of inlet liners, ionization techniques and columns are discussed and a summary of mass analyzers are also highlighted. Lastly, the role of retention index in metabolite identification and data normalization methods are presented. The purpose of this review is summarizing methods of sample storage, pretreatment, and GC–MS analysis that are mostly used in urine metabolomics studies. Specific emphasis is given to the critical steps within the GC–MS urine metabolomics that those new to this field need to be aware of and the remaining challenges that require further attention and studies.

A review of strategies for untargeted urinary metabolomic analysis using gas chromatography–mass spectrometry

Derivatization of carbohydrates for GC and GC–MS analyses

Characterization of sugar composition in Chinese royal jelly by ion chromatography with pulsed amperometric detection

Background and Objectives. Dracocephalum moldavica L. is an herbal medicine used to treat cardiovascular diseases in China. The purpose of this study was to assess the cardioprotective effect of D. moldavica L. extracts against H2O2-induced apoptosis and oxidative stress in H9c2 cells and to explore the mechanism behind this effect. Materials and Methods. The petroleum ether (petrol), dichloromethane (CH2Cl2), ethyl acetate (EtOAc), and n-butyl alcohol (n-BuOH) fractions were isolated from alcohol extracts of D. moldavica L. Total phenolic and flavonoid contents and in vitro antioxidant activities of different fractions were evaluated. H9c2 cells were then treated with D. moldavica L. extracts before challenging with H2O2. Cell viability was determined by colorimetric assay, and ELISA was used to measure the levels of lactate dehydrogenase (LDH), malondialdehyde (MDA), and superoxide dismutase (SOD). Apoptosis levels and mitochondrial membrane potential were measured by flow cytometry. The expressions of cell apoptosis regulatory proteins caspase-3, Bax, and Bcl-2 were determined by western blotting. Results. Our results demonstrated that the EtOAc fraction from D. moldavica L. ethanol extract, which is rich in phenolic and flavonoid active constituents, had the strongest free radical scavenging activity. Additionally, this fraction increased H2O2-induced reduction in cell viability, SOD activity, and mitochondrial membrane potential. It also reduced H2O2-induced elevation in ROS production, contents of LDH and MDA, and H9c2 apoptosis. We further found that the EtOAc fraction increased Bcl-2 expression, while it decreased caspase-3 and Bax expressions induced by H2O2 in H9c2 cells. Conclusions. Our data revealed that the EtOAc fraction from D. moldavica L. ethanol extract ameliorates H2O2-induced cardiotoxicity via antiapoptotic and antioxidant mechanisms.

/pdf/dracocephalum-moldavica-l-extracts-protect-h9c2-1wliuyn6l4.pdf

Dracocephalum moldavica L. Extracts Protect H9c2 Cardiomyocytes against H2O2-Induced Apoptosis and Oxidative Stress.

A simple method for the simultaneous derivatization of carbohydrates, polyols, amines and amino acids using hexamethyldisilazane and N,O-bis(trimethylsilyl)trifluoroacetamide was developed. This method allows the direct derivatization of urine samples without sample pretreatment before derivatization. The method was successfully used for analysis of the selected metabolites in urine samples of healthy individuals and neonates suffering from galactosemia. The limits of detection by positive chemical ionization gas chromatography with tandem mass spectrometry analysis were in the range of 1.0 mgL-1 for mannitol to 4.7 mgL-1 for glucose.

This article is protected by copyright. All rights reserved

Simultaneous analysis of carbohydrates, polyols and amines in urine samples using chemical ionization gas chromatography with tandem mass spectrometry

Hydroxybenzylidene hydrazines exhibit a wide spectrum of biological activities Here, we report synthesis and free radical scavenging activity of nine new N-(hydroxybenzylidene)-N′-[2,6-dinitro-4-(trifluoromethyl)]phenylhydrazines The chemical structures of these compounds were confirmed by 1H-NMR, 13C-NMR, 19F-NMR, IR spectroscopy, LC-MS, and elemental analysis The prepared compounds were tested for their activity to scavenge 2,2-diphenyl-1-picrylhydrazyl (DPPH), galvinoxyl radical (GOR), and 2,2′-azino-bis(3-ethylbenzothiazoline)-6-sulphonic acid (ABTS) radicals The free radical scavenging activity expressed as SC50 values of these compounds varied in a wide range, from a strong to no radical scavenging effect The most effective radical scavengers were hydroxybenzylidene hydrazines containing three hydroxyl groups in the benzylidene part of their molecules The prepared compounds were also tested for their activity to inhibit photosynthetic electron transport in spinach chloroplasts IC50 values of these compounds varied in wide range, from an intermediate to no inhibitory effect

Synthesis and Free Radical Scavenging Activity of New Hydroxybenzylidene Hydrazines

There are different criteria for assessing the appropriateness of an agglomeration technology in the deployment processing of dry, fine and dirty dust burdening in the communal and working environment Besides the benefit of the environment components, the agglomeration technology offers the possibility of re-processing the material as the primary raw material within a wide range of industries Preliminary tests have shown that the compressed material remains in the memory from the previous compression For returning the already processed material into a primary production, it is essential that it is reformed without the need for additional materials, a requirement that can be problematic This article deals with the modification of a powder material (powder dust from the manufacture of friction components) and the investigation of its properties before and after the compaction processing

/pdf/modification-of-powder-material-by-compaction-processing-4mojs2zbm3.pdf

Modification of powder material by compaction processing

At the present time, a great attention is being paid to the use of algae. Algae can adapt to different conditions and can produce substances corresponding to responsible environments. The main problem in their cultivation is the design of a suitable photoreactor. It should create the optimal conditions for their growth, which is mainly dependent on the contact of the algae with the light. The intensity of the light depends on the hydrodynamic conditions in the photoreactor and on its geometry. This paper deals with the study of kinetics of growth and gross biomass yield of biomass in laboratory photobioreactors, respecting their geometrical similarity as a basis for a possible scale-up. An optimal ratio between biomass growth rate and its gross biomass yield as a function of the photoreactor geometry is searched. Chlamydomonas reinhardtii were used as the model organism.

/pdf/optimalization-of-photoreactor-geometry-for-the-cultivation-2675jx002d.pdf

Optimalization of photoreactor geometry for the cultivation of chlamydomonas reinhardtii

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Simultaneous analysis of carbohydrates, polyols and amines in urine samples using chemical ionization gas chromatography with tandem mass spectrometry

Synthesis and Free Radical Scavenging Activity of New Hydroxybenzylidene Hydrazines

Modification of powder material by compaction processing

Optimalization of photoreactor geometry for the cultivation of chlamydomonas reinhardtii