scholarly journals HYBRID MOLECULES BASED ON ALKALOIDS

2021 ◽  
Vol 3 ◽  
pp. 67-82
Author(s):  
O.A. Nurkenov ◽  
◽  
S.D. Fazylov ◽  
G.K. Mukusheva ◽  
Ye.V. Minayeva ◽  
...  
Keyword(s):  
Biologically Active ◽  
Plant Metabolites ◽  
New Methods ◽  
Hybrid Molecules ◽  
Wide Range ◽  
Methods Of Synthesis ◽  
Low Toxicity ◽  
Leading Compounds ◽  
Diverse Biological Activity

This review has been summarized the data on the synthesis of new hybrid derivatives based on alkaloid molecules. At the same time, there have been analyzed methods for obtaining hybrid structures containing fragments of natural compounds molecules in combination with other biologically active plant metabolites, as leading compounds for the development of new pharmacologically valuable agents, with the aim of creating new original drugs. The combination of pharmacophoric residues in one molecule, namely various aromatic and heterocyclic substituents in the nucleoside position of natural alkaloids, opens up new possibilities for both the subsequent chemical modification of the polyfunctional derivatives obtained and their new diverse biological activity. Effective methods of synthesis have been developed on the basis of directed transformations of these compounds (or their precursors). A wide range of pharmaco-logical properties of combined compounds of these series with a combination of low toxicity is promising. Considering that the preparation of combined derivatives based on alkaloid molecules has been insufficiently studied, the targeted synthesis of new com-pounds is of interest both in terms of new medicinespreparation and the development of new methods of organic synthesis, as well as the molecules stereochemistry determination of a new series of compounds.

Privileged Structures in the Design of Potential Drug Candidates for Neglected Diseases

2019 ◽  
Vol 26 (23) ◽  
pp. 4323-4354 ◽  
Author(s):  
Ana Cristina Lima Leite ◽  
José Wanderlan Pontes Espíndola ◽  
Marcos Veríssimo de Oliveira Cardoso ◽  
Gevanio Bezerra de Oliveira Filho
Keyword(s):  
Biologically Active ◽  
Neglected Diseases ◽  
Financial Return ◽  
Drug Candidates ◽  
Lead Compounds ◽  
Wide Range ◽  
Methods Of Synthesis ◽  
Current Therapies ◽  
Resistant Strains ◽  
Privileged Structures

Background: Privileged motifs are recurring in a wide range of biologically active compounds that reach different pharmaceutical targets and pathways and could represent a suitable start point to access potential candidates in the neglected diseases field. The current therapies to treat these diseases are based in drugs that lack of the desired effectiveness, affordable methods of synthesis and allow a way to emergence of resistant strains. Due the lack of financial return, only few pharmaceutical companies have been investing in research for new therapeutics for neglected diseases (ND). Methods: Based on the literature search from 2002 to 2016, we discuss how six privileged motifs, focusing phthalimide, isatin, indole, thiosemicarbazone, thiazole, and thiazolidinone are particularly recurrent in compounds active against some of neglected diseases. Results: It was observed that attention was paid particularly for Chagas disease, malaria, tuberculosis, schistosomiasis, leishmaniasis, dengue, African sleeping sickness (Human African Trypanosomiasis - HAT) and toxoplasmosis. It was possible to verify that, among the ND, antitrypanosomal and antiplasmodial activities were between the most searched. Besides, thiosemicarbazone moiety seems to be the most versatile and frequently explored scaffold. As well, phthalimide, isatin, thiazole, and thiazolidone nucleus have been also explored in the ND field. Conclusion: Some described compounds, appear to be promising drug candidates, while others could represent a valuable inspiration in the research for new lead compounds.

scholarly journals Determination of carbohydrates in the herbal antidiabetic mixtures by GC-MC

2021 ◽  
Vol 71 (3) ◽  
pp. 429-443 ◽  
Author(s):  
Alona Savych ◽  
Svitlana Marchyshyn ◽  
Ivanna Milian
Keyword(s):  
Diabetes Mellitus ◽  
Zea Mays ◽  
Taraxacum Officinale ◽  
Urtica Dioica ◽  
Cichorium Intybus ◽  
Biologically Active ◽  
Mentha Piperita ◽  
Wide Range ◽  
Monomeric Composition

AbstractDue to the wide range of biologically active substances, the herbal mixtures can influence the development of diabetes mellitus and its complications. Carbohydrates attract particular attention due to their hypoglycemic, hypolipidemic, anticholesterolemic, antioxidant, antiinflammatory and detoxifying activities. The aim of this study was to investigate the content of carbohydrates through their monomeric composition in the herbal mixture samples: a) Urtica dioica leaf, Cichorium intybus roots, Rosa majalis fruits, Elymys repens rhizome, Taraxacum officinale roots, b) Arctium lappa roots, Elymys repens rhizome, Zea mays columns with stigmas, Helichrysum arenarium flowers, Rosa majalis fruits, c) Inula helenium rhizome with roots, Helichrysi arenarium flowers, Zea mays columns with stigmas, Origanum vulgare herb, Rosa majalis fruits, Taraxacum officinale roots, d) Cichorium intybus roots, Elymys repens rhizome, Helichrysum arenarium flowers, Rosa majalis fruits, Zea mays columns with stigmas and e) Urtica dioica leaf, Taraxacum officinale roots, Vaccinium myrtillus leaf, Rosa majalis fruits, Mentha piperita herb, which were used in Ukrainian folk medicine for the prevention and treatment of diabetes mellitus type 2.The carbohydrates were separated by gas chromatography-mass spectrometry after conversion into volatile aldononitrile acetate derivatives. The monomeric composition of polysaccharides was studied after their hydrolysis to form monosaccharides and poly-alcohols.Quantitative analyses of free carbohydrates showed that the predominant sugars were fructose, glucose and disaccharide – sucrose, in all samples. Concerning the determination of polysaccharide monomers after hydrolysis, glucose was the most abundant in all samples. The chromatographic study revealed a number of polyalcohols that are important for the treatment and prevention of progression of diabetes mellitus and its complications, namely, mannitol, pinitol and myo-inositol.

scholarly journals Phytoestrogens in bovine plasma and milk – LC-MS/MS analysis

2010 ◽  
Vol 28 (No. 4) ◽  
pp. 264-274 ◽  
Author(s):  
A. Krajčová ◽  
V. Schulzová ◽  
J. Lojza ◽  
L. Křížová ◽  
J. Hajšlová
Keyword(s):  
Biological Fluids ◽  
Structural Similarity ◽  
Biologically Active ◽  
Feeding Experiment ◽  
Plant Metabolites ◽  
Alternative Source ◽  
Biological Responses ◽  
Bovine Plasma ◽  
The Relationship

Phytoestrogens belong to a group of polyphenolic plant metabolites which induce biological responses, based on their structural similarity to 17β-estradiol. In order to investigate the relationship between the levels of these biologically active compounds and beneficial health effects, it is neccesary to quantify accurately their levels in foods and biological fluids. In this study, HPLC-MS/MS method for the determination of isoflavones genistein, daidzein, and estrogenic metabolite-equol in bovine plasma and milk was optimised and validated. The method allowed low limits of detection: 5, 2.5 and 0.5 ng/ml for genistein, daidzein and equol, respectively, thus enabling to determine the effect of phytoestrogen-rich diet on the concentration of isoflavones and the metabolite in biological fluids of cows. The feeding experiment, carried out with four dairy cows, showed that a soy-based diet significantly increased both plasma and milk contents of biologically potent equol, therefore, the latter commodity could be an alternative source of this estrogenic metabolite, namely for the consumers who are not capable to convert it from the isoflavone precursors consumed in the diet.

scholarly journals Secondary Metabolites-Derived Polymers: A Potential Approach to Diminish Microbial Infection

2018 ◽  
Author(s):  
Ahmed Al-Jumaili ◽  
Avishek Kumar ◽  
Kateryna Bazaka ◽  
Mohan V. Jacob
Keyword(s):  
Renewable Resources ◽  
Solid Phase ◽  
Biologically Active ◽  
Fungal Colonization ◽  
Attractive Alternative ◽  
Microbial Infection ◽  
Plant Metabolites ◽  
Secondary Plant Metabolites ◽  
Wide Range ◽  
Secondary Plant

The persistent issue of bacterial and fungal colonization of artificial implantable materials and decreasing efficacy of conventional systemic antibiotics used to treat implant-associated infections has led to the development of a wide range of antifouling and antibacterial strategies. This article reviews one such strategy where inherently biologically active renewable resources, i.e. secondary plant metabolites (SPMs) and their naturally occurring combinations (i.e. essential oils) are used for surface functionalization and synthesis of polymer thin films. With a distinct mode of antibacterial activity, broad spectrum of action and diversity of available chemistries, secondary plant metabolites present an attractive alternative to conventional antibiotics. However, their conversion from liquid to solid phase without significant loss of activity is not trivial. Using select examples, this article shows how plasma techniques provide a sufficiently flexible and chemically reactive environment to enable the synthesis of biologically-active polymer-coatings from volatile renewable resources.

scholarly journals Food safety: modern methods of multicomponent determination of pesticides

2021 ◽  
Vol 65 (4) ◽  
pp. 388-393
Author(s):  
Valerii N. Rakitskii ◽  
Natalia E. Fedorova
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Food Products ◽  
Measurement Methods ◽  
Biologically Active ◽  
Toxic Metabolite ◽  
Analytical Control ◽  
Chromatography Mass Spectrometry ◽  
Wide Range

Introduction. Analytical control of chemical contamination is essential in ensuring the safety of food products manufactured using pesticides. The development and testing of new methodological techniques for multicomponent measurement of the levels of residual amounts of biologically active ingredients are constantly in the field of view of analysts. Research objectives. To assess the suitability of the QuEChERS methodological approaches for the determination of a wide range of pesticides of various structures and physicochemical properties (up to 50 names of active substances) in food products and food raw materials of various compositions and origins (fruits, vegetables, cereals, rice, tea, coffee, milk, eggs and their derivatives, meat, offal). Material and methods. The measurements were carried out by tandem liquid chromatography-mass spectrometry and gas chromatography with a mass-selective detector, focused on screening and quantifying trace amounts of pesticides. The sample preparation procedure for analysis was carried out according to the QuEChERS method. Results. Multimethods have been created for the determination of residual amounts of pesticides in cereal grains (40 substances), fruits of vegetables and fruits (27 compounds), fruits of citrus crops (50 ingredients), 2,4-D acid in milk, eggs and by-products, fipronil and its toxic metabolite - sulfone in eggs, products of their processing (melange, dry egg white), muscle tissue and offal. The developments have supplemented the list of certified measurement methods included in the unified information fund of measurement methods of the Russian Federation. Conclusions. The unification of analytical methods for preparing samples of food products of various composition and origin for analysis, instrumentation of analytical laboratories with liquid and gas chromatography-mass spectrometry systems expand the possibilities of introducing group methods, ensure the readiness of testing centres to perform multi-purpose tests to identify and measure pesticide levels.

MODEL BIOMEMBRANES AS TEST OBJECTS FOR THE DETERMINATION OF CONCENTRATION RANGES OF HARMFUL CHEMICAL SUBSTANCES IN BIOLOGICAL MEDIUMS AND OBJECTS OF EXTERNAL ENVIRONMENT

2019 ◽  
pp. 33-45
Author(s):  
O. M. Alekseeva ◽  
A. V. Krementsova ◽  
A. V. Krivandin ◽  
O. V. Shatalova ◽  
Yu. A. Kim
Keyword(s):  
Biologically Active Substances ◽  
Biologically Active ◽  
Diffraction Scattering ◽  
Wide Range ◽  
Multilamellar Liposomes ◽  
Small Doses ◽  
Pre Treatment ◽  
Active Substances ◽  
Test Objects

The paper presents data on changes in model biomembranes (liposomes, erythrocyte shadows, erythrocytes) used as test objects to determine those ranges of concentrations of biologically active substances in which there is no violation of the structure or function of experimental objects. Melaphene, plant growth regulator used in small doses in seed pre-treatment, and antioxidant phenosan derivatives, phenoxane and IHFANs, have been used as biologically active substances. It was shown by DSC that phenosan derivatives at concentrations equal to 10-5 M and higher destroy the microdomain organization in the bilayers of phospholipid multilamellar liposomes and reshape protein microdomains in the shadows of red blood cells. Melaphene in small and large concentrations changes polymodal the microdomain organization in the bilayers of phospholipid multilamellar liposomes without destroying the structure and does not affect the protein microdomains in the shadows. An increase in the membrane permeability in isolated intact erythrocytes in the presence of melaphene in large and small concentrations has been revealed by means of spectral anaslysis. The method of small-angle diffraction scattering showed the absence of the effect of melaphene in a wide range of concentrations on the thickness of phospholipid bilayers and the order of their packaging in multilamellar liposomes.

scholarly journals SiO2@TiO2 Composite Synthesis and Its Hydrophobic Applications: A Review

Catalysts ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 171
Author(s):  
Alicia Rosales ◽  
Karen Esquivel
Keyword(s):  
Composite Material ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Research Information ◽  
Chemical Methods ◽  
Wide Range ◽  
Methods Of Synthesis ◽  
Low Toxicity ◽  
Physical And Chemical ◽  
And Chemical Properties

Titanium dioxide is well known for its photocatalytic properties and low toxicity, meanwhile, silicone dioxide exhibits hydrophobic and hydrophilic properties and thermal stability. The union of these two materials offers a composite material with a wide range of applications that relate directly to the combined properties. The SiO2-TiO2 composite has been synthesized through physical methods and chemical methods and, with adequate conditions, morphology, crystallinity, boundaries between SiO2-TiO2, among other properties, can be controlled. Thus, the applications of this composite are wide for surface applications, being primarily used as powder or coating. However, the available research information on this kind of composite material is still novel, therefore research in this field is still needed in order to clarify all the physical and chemical properties of the material. This review aims to encompass the available methods of synthesis of SiO2-TiO2 composite with modifiers or dopants, the application and known chemical and physical properties in surfaces such as glass, mortar and textile, including aspects for the development of this material.

scholarly journals Recent theoretical and practical applications of micellar liquid chromatography (MLC) in pharmaceutical and biomedical analysis

2012 ◽  
Vol 10 (3) ◽  
pp. 570-584 ◽  
Author(s):  
Piotr Kawczak ◽  
Tomasz Bączek
Keyword(s):  
Liquid Chromatography ◽  
Pharmaceutical Analysis ◽  
Micellar Liquid Chromatography ◽  
Biologically Active ◽  
Organic Modifiers ◽  
Active Compounds ◽  
Separation Techniques ◽  
Practical Applications ◽  
Wide Range

AbstractMicellar liquid chromatography (MLC) is an analytical technique belonging to the wide range of reversed-phase liquid chromatographic (RP-LC) separation techniques. MLC with the use of surfactant solutions above its critical micellar concentration (CMC) and the addition of organic modifiers is currently an important analytical tool with still growing theoretical considerations and practical applications in pharmaceutical analysis of drugs and other biologically active compounds. The use of MLC as an alternative, relatively much faster in comparison to conventional chromatographic separation techniques has several advantages, especially as being suitable for screening pharmaceutical analysis. The analytical data received from MLC analysis are considered a useful source of information to predict passive drug absorption, drug transport and other pharmacokinetics and physicochemical measures of pharmaceutical substances. In the review several MLC assays for determination of drugs and other active compounds in biological samples were compared and critically discussed. The presented overview provides information on recent applications and achievements connected with the practical use of MLC. The review covers fields of interest related to theory and mechanism of MLC separation, direct applications of MLC in pharmaceutical analysis, including optimization and efficiency of separation with the use of modification of stationary phase and mobile phase compositions as well as the determination of physicochemical characteristics of drugs by MLC.

scholarly journals Current Methods for the Extraction and Analysis of Isothiocyanates and Indoles in Cruciferous Vegetables

Analytica ◽  
2021 ◽  
Vol 2 (4) ◽  
pp. 93-120
Author(s):  
Sofia Karanikolopoulou ◽  
Panagiota-Kyriaki Revelou ◽  
Marinos Xagoraris ◽  
Maroula G. Kokotou ◽  
Violetta Constantinou-Kokotou
Keyword(s):  
High Performance ◽  
Degradation Products ◽  
Analytical Techniques ◽  
Extraction Methods ◽  
Analytical Determination ◽  
Cruciferous Vegetables ◽  
Plant Metabolites ◽  
Secondary Plant Metabolites ◽  
Wide Range

Cruciferous vegetables are characterized by the presence of sulfur-containing secondary plant metabolites known as glucosinolates (GLS). The consumption of cruciferous vegetables such as broccoli, cabbage, rocket salad, and cauliflower has been related to the prevention of non-communicable diseases. Their beneficial effects are attributed to the enzymatic degradation products of GLS, e.g., isothiocyanates and indoles. Owing to these properties, there has been a shift in the last few years towards the research of these compounds and a wide range of methods for their extraction and analytical determination have been developed. The aim of this review is to present the sample preparation and extraction procedures of isothiocyanates and indoles from cruciferous vegetables and the analytical methods for their determination. The majority of the references that have been reviewed are from the last decade. Although efforts towards the application of eco-friendly non-conventional extraction methods have been made, the use of conventional solvent extraction is mainly applied. The major analytical techniques employed for the qualitative and quantitative analysis of isothiocyanates and indoles are high-performance liquid chromatography and gas chromatography coupled with or without mass spectrometry detection. Nevertheless, the analytical determination of isothiocyanates presents several problems due to their instability and the absence of chromophores, making the simultaneous determination of isothiocyanates and indoles a challenging task.

scholarly journals The spectrophotometric determination of A-vitamin activity of carotenoid-containing raw material

2021 ◽  
pp. 17-26
Author(s):  
V.V. Velichko ◽  
◽  
D.S. Kruglov ◽  
Keyword(s):  
Spectrophotometric Determination ◽  
Raw Materials ◽  
Biologically Active ◽  
Raw Material ◽  
Health Improvement ◽  
Plant Materials ◽  
Plant Raw Materials ◽  
Wide Range ◽  
Vitamin Activity

Carotenoids are of interest as precursors of vitamin A, which has a wide range of pharmacological effects — antioxidant, immunomodulatory, participating in photoreception, etc. The aim of the research was to develop a technique for the spectrophotometric determination of the A-vitamin activity of carotenoids-rich medicinal plant raw materials (MPRM). The objects of research were the traditional sources of carotenoids — sea buckthorn, carrot, pumpkin and wild rose. A method is proposed for determining the content of individual carotenoids in MPRM by optical density at wavelengths corresponding to the characteristic peaks of α-carotene, β-carotene and lycopene. It has been shown that it is preferable to use isopropyl alcohol as the most effective solvent. Taking into account the content of specific carotenoids makes it possible to determine the A-vitamin activity of the sum of carotenoids extracted from plant materials, and, accordingly, to increase the efficiency of the use of herbal preparations and biologically active additives for health improvement.

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