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1.
Chromatographia ; 80(6): 923-930, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28725082

RESUMEN

Thin layer techniques proved their usefulness in the analysis of plant extract material. Thanks to their low operation costs, high sample throughput and possibility to gather chromatographic data for the whole sample in a single act, they allowed to find, and in some cases identify, active ingredients often hidden in sophisticated plant extract matrices. It was also proved that the presence of a magnetic field changes the retention of some substances, and moreover changes the separation efficiency of chromatographic systems. In the presented experiment, retention, efficiency and separation abilities of TLC chromatographic systems for mixtures of alkaloids under the influence of magnetic field depending on inductivity of the magnetic field, the saturation of chromatographic chamber and quantity of chromatographed substances were investigated. The results obtained were tested on real plant extracts that revealed the ability of chromatography in a magnetic field for separation of ternary and quaternary alkaloids from Chelidonium majus L. Our experiments proved that the presence of magnetic field induction lines perpendicular to the chromatographic plate plane can influence the width and retention of chromatographed substances, and can be considered as a tool for separation adjustment of plant extracts containing ternary and quaternary alkaloids.

2.
Chromatographia ; 76: 1327-1332, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24078741

RESUMEN

Planar chromatography is a very useful tool for analysis of wide range of different mixtures. Thanks to its possibility for rapid separation of large number of samples simultaneously, low solvent consumption and ability to analyse rough material allow to receive precise and reliable results in short time and low cost. Miniaturization of planar techniques brings a lot of advantages, such as shortening distance and time of chromatogram development, and further lowering of solvent consumption. Besides, it often allows to improve separation parameters and raise efficiency of chromatographic system. In this paper, ability of analysis of tropane alkaloids mixture from Datura Inoxia Mill. extract using conventional TLC technique with five micro TLC techniques (short distance TLC, HPTLC, UTLC, OPLC and ETLC) in maximally closed chromatographic conditions was compared in order to present abilities of micro TLC techniques in plant material analysis.

3.
Pharmacol Rep ; 60(4): 439-63, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18799813

RESUMEN

Secondary metabolites of Solanaceae plants, sharing tropane skeleton as a common structural feature, are sharply divided into two classes: tropine and ecgonine derivatives. The first group, represented by well known alkaloids: atropine and scopolamine, which are considered to be model anticholinergic drugs, continues to provide inspiration in the search for more selective muscarinic receptor antagonists. The second class accommodates one of the principal drugs of abuse, cocaine. Synthesis of much needed cocaine antagonists, despite extensive research, has not been particularly successful. Therefore, new concepts of cocaine abuse treatment resort to immunotherapy and biotechnology. Contemporary pharmaceutical industry manufactures over 20 active pharmaceutical substances containing tropane moiety in their structure, which are applied as mydriatics, antiemetics, antispasmodics, anesthetics and bronchodilators. There are two sources of raw materials for this industrial activity: natural products isolated from cultivated transgenic plants (mainly scopolamine and atropine from Australian Duboisia) and chemical synthesis based on common intermediate: tropinone, which can be further transformed by synthetic means to the following classes of compounds: tropine and its esters (tropeines), scopine and nortropine derivatives, and tropane quaternary ammonium salts. This survey focuses on new developments in chemistry and pharmacology of tropane derivatives, particularly in view of their prospective industrial applications as therapeutics.


Asunto(s)
Química Farmacéutica/métodos , Alcaloides Solanáceos , Tropanos/clasificación , Tropanos/síntesis química , Trastornos Relacionados con Cocaína/tratamiento farmacológico , Industria Farmacéutica/estadística & datos numéricos , Humanos , Alcaloides Solanáceos/química , Alcaloides Solanáceos/farmacología , Alcaloides Solanáceos/uso terapéutico , Relación Estructura-Actividad , Tropanos/aislamiento & purificación
4.
J Chromatogr Sci ; 46(4): 291-7, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18402718

RESUMEN

Some standards of the alkaloids and synthetic or natural mixtures are separated by two-dimensional thin-layer chromatography (TLC) on different adsorbent layers. Normal- and reversed-phase systems are used to obtain significant differences in the separation selectivity. Optimization of the one-dimensional TLC separation of the alkaloids' standards is performed on cyanopropyl-silica, RP18W, and silica layers in various eluents containing (besides diluent and modifier) silanol blockers, such as diethyl amine or ammonia. The most selective systems are used for the separation of the alkaloids' mixtures by two-dimensional TLC with an adsorbent gradient method. The mixtures of alkaloids or plant extracts (Chelidonium majus, Fumaria officinalis, or Glaucium flavum) are chromatographed in system I; the plates are connected with the plate pre-coated with various adsorbent, and partly separated fractions are transferred to the second layer and developed in system II. CN-silica-RP18W and CN-silica-silica are used as the connected layers. The alkaloids are identified by R(F) values of standards, and the components of plant extracts are identified in both systems, and by the comparison of UV spectra obtained in diode array detector densitometry.


Asunto(s)
Alcaloides/aislamiento & purificación , Cromatografía en Capa Delgada/métodos , Extractos Vegetales/química , Dióxido de Silicio , Espectrofotometría Ultravioleta
5.
J Chromatogr Sci ; 45(7): 447-54, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17725873

RESUMEN

Selected alkaloids are chromatographed on cyanopropyl-silica thin layers using various nonaqueous and aqueous eluents. Because of the strong retention of these basic compounds, nonaqueous eluents containing medium polar diluents, strongly polar modifiers, and silanol blockers (ammonia or diethylamine) are required for separation. Likewise, aqueous eluents containing modifiers (acetonitrile, methanol, and tetrahydrofuran), buffered aqueous solutions at pH 2-8, ion-pair reagents [octane sulfonic acid sodium salt, sodium dodecyl sulphate, and bis-(2-ethylhexyl)phosphoric acid], or silanol blockers (ammonia, tetrabutyl ammonium chloride, and diethyl amine) are investigated. The separation selectivity as well as spot symmetry and efficiency system in the applied eluent systems are analyzed. The most selective and efficient systems are used in two-dimensional separations of isoquinoline alkaloids' mixture and the plant extracts Chelidonium majus, Fumaria officinalis, and Glaucium flavum. Two-dimensional thin-layer chromatography on cyanopropyl layer with diode array detection densitometry enables the separation and identification of some alkaloids in plant extracts.


Asunto(s)
Alcaloides/aislamiento & purificación , Cromatografía en Capa Delgada/instrumentación , Extractos Vegetales/química
6.
Acta Pol Pharm ; 60(2): 133-8, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-13678323

RESUMEN

Eleven new derivatives of chelidonine I, obtained by functionalization of the alkaloid hydroxyl group, have been tested for CNS activity in mice exhibiting statistically significant effects.


Asunto(s)
Alcaloides/química , Alcaloides/farmacología , Alcaloides de Berberina , Sistema Nervioso Central/efectos de los fármacos , Fenantridinas , Animales , Benzofenantridinas , Sistema Nervioso Central/fisiología , Evaluación Preclínica de Medicamentos/métodos , Masculino , Ratones
7.
Acta Pol Pharm ; 59(2): 149-60, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12365608

RESUMEN

Alkaloids with tropane skeleton, present in many species of Solanaceae family, constitute important raw materials for variety of pharmaceutical preparations. Although basic facts concerning chemistry and pharmacology of these compounds date back to XIX century, the wealth of data accumulated recently has challenged many established opinions, particularly in the field of biogenesis. Advances in analytical techniques which made this progress possible are discussed, in reference to contemporary requirements for specification of active pharmaceutical ingredients.


Asunto(s)
Alcaloides/química , Tropanos/química , Alcaloides/aislamiento & purificación , Preparaciones Farmacéuticas/química , Preparaciones Farmacéuticas/aislamiento & purificación , Fitoterapia/métodos , Solanaceae/química , Tropanos/aislamiento & purificación
8.
Acta Pol Pharm ; 59(1): 61-4, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12026115

RESUMEN

The high-performance liquid chromatographic method using two stationary phases: RP-18 and cyanopropyl silica for the analysis of some alkaloids in Chelidonium maius L. extracts is performed. The extract was chromatographed using a mobile phase composed of an organic modifier (acetonitrile, methanol, tetrahydrofuran or 1,4-dioxan), phosphate buffer and sodium octadecylsulfate or di (2-ethyl hexyl) orthophosphoric acid (HDEHP) as ion-pairing reagents. The influence of the different kind of stationary phase and organic modifiers on retention has been compared. In order to improve the selectivity of separation and peak shape, gradient elution was applied.


Asunto(s)
Alcaloides/análisis , Chelidonium/química , Alcaloides/química , Cromatografía Líquida de Alta Presión/métodos , Extractos Vegetales/análisis , Extractos Vegetales/química , Estructuras de las Plantas/química , Silanos/química
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