scholarly journals Caffeic Acid/Eu(III) Complexes: Solution Equilibrium Studies, Structure Characterization and Biological Activity

2022 ◽  
Vol 23 (2) ◽  
pp. 888
Author(s):  
Żaneta Arciszewska ◽  
Sofia Gama ◽  
Monika Kalinowska ◽  
Grzegorz Świderski ◽  
Renata Świsłocka ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Biological Activity ◽  
Metal Complex ◽  
Caffeic Acid ◽  
Structure Characterization ◽  
Biological Information ◽  
Structure Stability ◽  
Ionization Mass ◽  
Molecular Formula ◽  
The Eu

Caffeic acid (CFA) is one of the various natural antioxidants and chemoprotective agents occurring in the human diet. In addition, its metal complexes play fundamental roles in biological systems. Nevertheless, research on the properties of CFA with lanthanide metals is very scarce, and little to no chemical or biological information is known about these particular systems. Most of their properties, including their biological activity and environmental impact, strictly depend on their structure, stability, and solution behaviour. In this work, a multi-analytical-technique approach was used to study these relationships for the Eu(III)/CFA complex. The synthesized metal complex was studied by FT-IR, FT-Raman, elemental, and thermal (TGA) analysis. In order to examine the chemical speciation of the Eu(III)/CFA system in an aqueous solution, several independent potentiometric and spectrophotometric UV-Vis titrations were performed at different M:L (metal:ligand) and pH ratios. The general molecular formula of the synthesized metal complex in the solid state was [Eu(CFA)3(H2O)3]∙2H2O (M:L ratio 1:3), while in aqueous solution the 1:1 species were observed at the optimum pH of 6 ≤ pH ≤ 10, ([Eu(CFA)] and [Eu(CFA)(OH)]−). These results were confirmed by 1H-NMR experiments and electrospray-ionization mass spectrometry (ESI-MS). To evaluate the interaction of Eu(III)/CFA and CFA alone with cell membranes, electrophoretic mobility assays were used. Various antioxidant tests have shown that Eu(III)/CFA exhibits lower antioxidant activity than the free CFA ligand. In addition, the antimicrobial properties of Eu(III)/CFA and CFA against Escherichia coli, Bacillus subtilis and Candida albicans were investigated by evaluation of the minimum inhibitory concentration (MIC). Eu(III)/CFA shows higher antibacterial activity against bacteria compared to CFA, which can be explained by the highly probable increased lipophilicity of the Eu(III) complex.

scholarly journals A Novel Thiosemicarbazide-Based Fluorescent Chemosensor for Hypochlorite in Near-Perfect Aqueous Solution and Zebrafish

Chemosensors ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 65
Author(s):  
Minji Lee ◽  
Donghwan Choe ◽  
Soyoung Park ◽  
Hyeongjin Kim ◽  
Soomin Jeong ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Reactive Oxygen Species ◽  
Aqueous Solution ◽  
Fluorescence Quenching ◽  
Limit Of Detection ◽  
Fluorescent Sensor ◽  
Ionization Mass ◽  
Oxygen Species ◽  
Marked Selectivity ◽  
Uv Visible

A novel thiosemicarbazide-based fluorescent sensor (AFC) was developed. It was successfully applied to detect hypochlorite (ClO−) with fluorescence quenching in bis-tris buffer. The limit of detection of AFC for ClO− was analyzed to be 58.7 μM. Importantly, AFC could be employed as an efficient and practical fluorescent sensor for ClO− in water sample and zebrafish. Moreover, AFC showed a marked selectivity to ClO− over varied competitive analytes with reactive oxygen species. The detection process of AFC to ClO− was illustrated by UV–visible and fluorescent spectroscopy and electrospray ionization–mass spectrometry (ESI–MS).

scholarly journals Electrochemiluminescence Study of Europium (III) Complex with Coumarin3-Carboxylic Acid

2008 ◽  
Vol 2008 ◽  
pp. 1-6 ◽  
Author(s):  
Stefan Lis ◽  
Krzysztof Staninski ◽  
Tomasz Grzyb
Keyword(s):  
Aqueous Solution ◽  
Spectral Analysis ◽  
Energy Transfer ◽  
Solid State ◽  
Carboxylic Acid ◽  
Elemental Analysis ◽  
Aluminium Electrode ◽  
The Eu

The europium (III) complex of coumarin-3-carboxylic acid (C3CA) has been prepared and characterized on the basis of elemental analysis, IR, and emission (photoluminescence and electrochemiluminescence) spectroscopy. The synthesised complex having a formula Eu was photophysically characterized in solution and in the solid state. Electrochemiluminescence, ECL, of the system containing the Eu(III)/C3CA complex was studied using an oxide-covered aluminium electrode. The goal of these studies was to show the possibility of the use of electrochemical excitation of the Eu(III) ion in aqueous solution for emission generation. The generated ECL emission was very weak, and therefore its measurements and spectral analysis were carried out with the use of cut-off filters method. The studies proved a predominate role of the ligand-to-metal energy transfer (LMET) in the generated ECL.

scholarly journals EFFECT OF RADICAL SCAVENGERS AND PROPOSED PATHWAYS FOR DEGRADATION OF AZO DYE IN AQUEOUS SOLUTION UNDER PRESENCE OF IRON(III) AND PERSULPHATE

2017 ◽  
Vol 60 (4) ◽  
pp. 88
Author(s):  
Heng Zhong ◽  
Hui Zhao ◽  
Jun Li ◽  
Lei Sun ◽  
Aihua Xu ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Carboxylic Acids ◽  
Azo Dye ◽  
Water Discharge ◽  
Radical Scavenging ◽  
Degradation Process ◽  
Ionization Mass ◽  
Radical Scavengers ◽  
Acid Orange 7 ◽  
Degradation Of Azo Dye

The degradation process of Acid Orange 7 (AO7) in aqueous solutions by iron(III) under activation by persulfate (PS, S2O82-) oxidation and Visible (Vis) light (≥420 nm) exposure has been studied. The radical scavenging effect was examined by using ethanol (EtOH), tert-butyl alcohol (TBA) and sodium azide to state that the hydroxyl radical (·OH) is regarded as the predominant reactive oxidant for the AO7 decolorization, while the sulfate radical (SO4·-) and singlet oxygen(1O2) are also make their contribution to dye's degradation. The reaction intermediates were determined by electrospray ionization-mass spectrometry (ESI-MS) analysis, and a probable degradation pathway mechanism has been proposed. It was suggested, that firstly an initial successive radical attacks the N atom of the dye, which decompose to p-phenolsulfonic acid and 1,2-naphthaquinone through the contemporaneous break of two C-N bonds. Afterwards, subsequent oxidation of these products and loss of the −SO3− group are observed. Finally, the acyclic carboxylic acids are formed from the central ring-opening, and then the further oxidation to simple carboxylic acids is evident. The work can provide a simple, effective and economic system for the treatment of non-biodegradable azo dye. The recommendations were proposed on organization of an effective quality control of technological water discharge and products of its processing at the local wastewater treatment facilities of industrial plants for prevention of the ingress of hazardous biological substances to the hydrosphere.Forcitation:Heng Zhong, Hui Zhao, Jun Li, Lei Sun, Aihua Xu, Dongsheng Xia, Nevsky A.V. Effect of radical scavengers and proposed pathways for degradation of azo dye in aqueous solution under presence of iron (III) and persulphate. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2017. V. 60. N 4. P. 88-94.

THE TYPES OF BIOLOGICAL DATABASES (BIOBANKS)

2021 ◽  
pp. 136-148
Author(s):  
Elena S. Boltanova ◽  
◽  
Maria P. Imekova ◽  
Keyword(s):  
Biological Samples ◽  
Local Level ◽  
Legal Regulation ◽  
Biological Data ◽  
Biological Information ◽  
Biological Databases ◽  
Legal Regime ◽  
Eu Countries ◽  
Legal Method ◽  
The Eu

In the world, it is customary to create biological databases of different species. And initially, the databases for the investigation of crimes were widespread. However, later, when their potential and benefits, including for medicine, were assessed, the databases for other areas appeared. Russia was no exception in this regard. Although, in our country, unlike foreign states, the activities of biological databases based on purposes other than the disclosure of crimes are practically not regulated in any way. This article deals with the analysis of legal regulation of biobanks in the Russian Federation and abroad. Special attention is paid to the classification of biobanks. The purpose of the study is to determine the feasibility in the legislative regulation of their activities, as well as the patterns in such a regulation. To achieve this goal, the authors studied extensive regulatory material, which included EU directives and national regulations of the EU member states. The methodological basis of the study was the general scientific and private scientific meth-ods of research. Of course, such private scientific research methods as the comparative-legal method and the formal legal method have been widely used. Due to the comparative legal analysis, it is established that the EU countries have a high level of legislative activity in terms of determining the legal regime of biological databases. All countries recognize the specifics of such a legal regime, which can largely be explained by a special legal nature of biological samples and biological data. In this regard, the following issues related to the activities of biological databases are reflected everywhere in the EU countries at the level of law: the procedure for their creation; the procedure for receiving, processing, storing and transmitting biological samples and the data obtained on their basis; the rights and obligations of database creators and persons who have provided their biological samples and biological data about themselves; a set of measures aimed at protecting the rights and interests of donors and third parties, etc. As it seems, a similar approach to the regulation of the activities of biological bases estab-lished not for the investigation of crimes should be implemented by Russia. At the same time, special attention should be paid to the research of biological databases. In the Russian Federa-tion, they are created, as a rule, at the local level. Their main drawback is that they are sepa-rate sources of limited biological information, functioning independently of each other while comprehensive (concentrated in one place) information can bring invaluable benefits and advantages for Russian science and medicine as a whole. However, this requires the estab-lishment of an appropriate legal framework.

scholarly journals Biological Activity of Cannabis sativa L. Extracts Critically Depends on Solvent Polarity and Decarboxylation

Separations ◽  
2020 ◽  
Vol 7 (4) ◽  
pp. 56
Author(s):  
Guillermo Moreno-Sanz ◽  
Carlos Ferreiro Vera ◽  
Carolina Sánchez-Carnerero ◽  
Xavier Nadal Roura ◽  
Verónica Sánchez de Medina Baena
Keyword(s):  
Biological Activity ◽  
Pharmacological Activity ◽  
Transcriptional Activation ◽  
Cannabis Sativa ◽  
Solvent Polarity ◽  
Solvent Selection ◽  
Extraction And Purification ◽  
Key Aspects ◽  
The Eu

Minor cannabinoid and non-cannabinoid molecules have been proposed to significantly contribute to the pharmacological profile of cannabis extracts. Phytoplant Research has developed highly productive cannabis cultivars with defined chemotypes, as well as proprietary methods for the extraction and purification of cannabinoids. Here, we investigate the effect of solvent selection and decarboxylation on the composition and pharmacological activity of cannabis extracts. A library of forty cannabis extracts was generated from ten different cannabis cultivars registered by Phytoplant Research at the EU Community Plant Variety Office. Plant material was extracted using two different solvents, ethanol and hexane, and crude extracts were subsequently decarboxylated or not. Cannabinoid content in the resulting extracts was quantified, and biological activity was screened in vitro at three molecular targets involved in hypoxia and inflammation (NF-κB, HIF-1α and STAT3). Changes in transcriptional activation were strongly associated to solvent selection and decarboxylation. Two decarboxylated extracts prepared with hexane were the most potent at inhibiting NF-κB transcription, while HIF-1α activation was preferentially inhibited by ethanolic extracts, and decarboxylated extracts were generally more potent at inhibiting STAT3 induction. Our results indicate that solvent selection and proper decarboxylation represent key aspects of the standardized production of cannabis extracts with reproducible pharmacological activity.

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