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1.
Molecules ; 23(7)2018 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-30037105

RESUMO

Previously tested n-hexane extracts of the Scorzonera latifolia showed promising bioactivity in vivo. Because triterpenes could account for this activity, n-hexane extracts were analyzed by HPLC to identify and quantify the triterpenes as the most abundant constituents. Other Scorzonera and Podospermum species, potentially containing triterpenic aglycones, were included in the study. An HPLC method for simultaneous determination of triterpene aglycones was therefore developed for analysis of Podospermum and Scorzonera species. n-Hexane extracts of root and aerial parts of S. latifolia, ten other Scorzonera species and two Podospermum species were studied to compare the content of triterpenes. HPLC was used for the qualitative and quantitative analysis of α-amyrin, lupeol, lupeol acetate, taraxasteryl acetate, 3-ß-hydroxy-fern-7-en-6-one acetate, urs-12-en-11-one-3-acetyl, 3-ß-hydroxy-fern-8-en-7-one acetate, and olean-12-en-11-one-3-acetyl. Limits of detection and quantification were determined for each compound. HPLC fingerprinting of n-hexane extracts of Podospermum and Scorzonera species revealed relatively large amounts of triterpenes in a majority of investigated taxa. Lupeol, lupeol acetate, and taraxasteryl acetate were found in a majority of the species, except S. acuminata. The presence of α-amyrin, 3ß-hydroxy-fern-7-en-6-one-acetate, urs-12-en-11-one-3-acetyl, 3ß-hydroxy-fern-8-en-7-one-acetate, and olean-12-en-11-one-3-acetyl was detected in varying amounts. The triterpene content could correlate with the analgesic and anti-inflammatory activity of Scorzonera, which was previously observed and Scorzonera species that have been determined to contain triterpenes in large amounts and have not yet been tested for their analgesic activity should be tested for their potential analgesic and anti-inflammatory potential. The presented HPLC method can be used for analysis of triterpene aglycones, for example dedicated to chemosystematic studies of the Scorzonerinae.


Assuntos
Asteraceae/química , Cromatografia Líquida de Alta Pressão , Compostos Fitoquímicos/química , Extratos Vegetais/química , Scorzonera/química , Triterpenos/química , Hexanos , Estrutura Molecular , Sensibilidade e Especificidade
2.
Radiat Prot Dosimetry ; 198(9-11): 681-686, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-36005979

RESUMO

Organic inclusions in lime binders provide useful samples for radiocarbon dating of historical objects. Two Czech castles Týrov and Pysolec from Late Middle Ages were explored, and tens of charcoals were found in their walls. The radiocarbon content of the charcoals was measured with accelerator mass spectrometry. The dating results showed that none of the charcoals were younger than the known historical ages (Týrov: 1260 - 1270, Pysolec: 1300 - 1340), but some were considerably older. Two charcoals from Pysolec castle dated to Palaeolithic, likely originating from fluvial sediments added as an aggregate to the mortar. When excluding these two charcoals, the others indicated most likely dates being 50-100 y older than the building dates of the castles. This systemic effect corresponds to the age of wood used for lime burning and shall be accounted for when dating mortars using charcoals.


Assuntos
Carvão Vegetal , Datação Radiométrica , Datação Radiométrica/métodos , Madeira
3.
J Ethnopharmacol ; 248: 112296, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-31610262

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Morus alba L. is used in traditional Chinese medicine for the treatment of various diseases, including bacterial infections and inflammation. As a rich source of phenolic compounds, the plant is an object of many phytochemical and pharmacological studies. AIM OF THE STUDY: The aim of the study was to isolate and evaluate possible parallel antiviral, antibacterial, and anti-inflammatory activities of phenolic mulberry compounds. MATERIALS AND METHODS: Extensive chromatographic separation of mulberry root bark extract and in vitro biological screening of 26 constituents identified promising candidates for further pharmacological research. Selected compounds were screened for anti-infective and anti-inflammatory activities. Antiviral activity was determined by the plaque number reduction assay and by the titer reduction assay, antibacterial using broth microdilution method, and anti-inflammatory activity using COX Colorimetric inhibitor screening assay kit. One compound was evaluated in vivo in carrageenan-induced paw-edema in mice. RESULTS: Five prenylated compounds 1, 2, 8, 9, and 11, together with a simple phenolic ester 13, exhibited inhibitory activity against the replication of herpes simplex virus 1 (HSV-1) or herpes simplex virus 2 (HSV-2), with IC50 values ranging from 0.64 to 1.93 µg/mL, and EC50 values 0.93 and 1.61 µg/mL. Molecular docking studies demonstrated the effects of the active compounds by targeting HSV-1 DNA polymerase and HSV-2 protease. In antibacterial assay, compounds 1, 4, 11, and 17 diminished the growth of all of the Gram-positive strains tested, with MIC values of 1-16 µg/mL. The anti-inflammatory ability of several compounds to inhibit cyclooxygenase 2 (COX-2) was tested in vitro, and compound 16 displayed greater activity than the indomethacin, positive control. Mulberrofuran B (11) showed anti-inflammatory activity in vivo against carrageenan-induced paw-edema in mice. CONCLUSIONS: Experimental investigation showed promising antiviral, antibacterial, and/or anti-inflammatory activities of the phenolic mulberry constituents, often with multiple inhibitory effects that might be used as a potential source of new medicine.


Assuntos
Diabetes Mellitus/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Morus , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Linhagem Celular , Diabetes Mellitus/metabolismo , Glucose/metabolismo , Glicogênio/metabolismo , Hipoglicemiantes/farmacologia , Resistência à Insulina , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Folhas de Planta , Ratos , Espécies Reativas de Oxigênio/metabolismo
4.
Fitoterapia ; 78(6): 437-9, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17604916

RESUMO

Antioxidant activity of methanolic extracts from inflorescence rachises, corollas, calyxes, leaves, valves of capsules and hypertrophied placenta of Catalpa bignonioides by 1,1-diphenyl-2-picrylhydrazyl reduction (DPPH) and tyrosine nitration inhibition induced by peroxynitrite was tested.


Assuntos
Antioxidantes/farmacologia , Bignoniaceae , Fitoterapia , Extratos Vegetais/farmacologia , Antioxidantes/administração & dosagem , Antioxidantes/química , Antioxidantes/uso terapêutico , Compostos de Bifenilo , Flores , Humanos , Picratos/química , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico , Folhas de Planta , Tirosina/química
5.
Artigo em Inglês | MEDLINE | ID: mdl-16936909

RESUMO

The present 15 days study was undertaken to evaluate the cardioprotective potential of the prenylated isoflavones osajin and pomiferin isolated from the infructences of Maclura pomifera, Moraceae, against ischemia-reperfusion induced injury in rat hearts as a model of antioxidant-based composite therapy. The study was performed on isolated, modified Langendorff-perfused rat hearts and the ischemia of heart was induced by stopping coronary flow for 30 min followed by 60 min of reperfusion (14 ml min(-1)). The Wistar rats were divided into four groups. The first treatment group received osajin (5 mg/kg/day in 0.5% Avicel); the second treatment group received pomiferin (5 mg/kg/day in 0.5% Avicel); the placebo group received only 0.5 Avicel; the last was an untreated control group. Biochemical indicator of oxidative damage-lipid peroxidation product malondialdehyde, antioxidant enzymes - superoxide dismutase, glutathione peroxidase, total antioxidant activity in serum and myocardium were evaluated. The effect of osajin and pomiferin on cardiac function, left ventricular end-diastolic pressure, left ventricular pressure and peak positive +dP/dt ischemia and reperfusion, also was examined. The results demonstrate that osajin and pomiferin attenuates the myocardial dysfunction provoked by ischemiareperfusion. This was confirmed by an increase in both antioxidant enzyme values and total antioxidant activity. The cardioprotection provided by osajin and pomiferin treatment results from the suppression of oxidative stress and this correlates with improved ventricular function.


Assuntos
Benzopiranos/uso terapêutico , Isoflavonas/uso terapêutico , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Fitoterapia , Extratos Vegetais/uso terapêutico , Animais , Técnicas In Vitro , Masculino , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Miocárdio/metabolismo , Ratos , Ratos Wistar
6.
Toxicology ; 208(1): 81-93, 2005 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-15664435

RESUMO

Cytochrome P4501A activity, oxidative stress and inhibition of gap junctional intercellular communication (GJIC) are involved in metabolic activation of promutagens and tumor-promoting activity of various xenobiotics, and their prevention is considered to be an important characteristic of chemoprotective compounds. In this study, a series of 31 chalcones and their corresponding dihydroderivatives, substituted in 2,2'-, 3,3'-, 4- or 4'-position by hydroxyl or methoxy group, were tested for their ability to inhibit Fe(II)/NADPH-enhanced lipid peroxidation and cytochrome P4501A-dependent 7-cethoxyresorufin-O-deethylase (EROD) activity in rat hepatic microsomes. Effects of the compounds on GJIC were determined in rat liver epithelial WB-F344 cells. Most of the chalcones and dihydrochalcones inhibited EROD activity in a dose-dependent manner at the range 0.25-25 microM, which was comparable to model flavonoid inhibitors alpha-naphthoflavone and quercetin. The chalcones exhibited higher inhibition activity than the corresponding dihydroderivatives. Mono and dihydroxylated chalcones, and dihydrochalcones showed none or only a weak antioxidant activity; trihydroxyderivatives inhibited in vitro lipid peroxidation significantly only at 50 microM concentration. Potential adverse effects, namely inhibition of GJIC and/or cytotoxicity were detected after treatment of WB-F344 cells with a number of chalcone and dihydrochalcone derivatives, suggesting that they should be excluded from additional screening as chemoprotective compounds. Chalcones and dihydrochalcones substituted at 4- and/or 4'-position, which elicited no inhibition of GJIC, were further tested for the potential enhancing effects on GJIC. The present data seem to suggest that 4-hydroxy, 2',4'-dihydroxy-3-methoxy, 2,4,4'-trihydroxy, and 2',4,4'-trihydroxychalcone, 2',4-dihydroxy and 2'-hydroxy-3,4-dimethoxydihydrochalcone might be promising chemoprotective compounds against CYP1A activity, and partly also against oxidative damage without inducing adverse effects, such as GJIC inhibition. In general, determination of potencies of tested compounds to inhibit GJIC should be involved in any set of methods for the in vitro screening of chemoprotective characteristics of potential drugs, in order to reveal their potential adverse effects associated with tumor promotion.


Assuntos
Carcinógenos/toxicidade , Chalconas/farmacologia , Chalconas/toxicidade , Sistema Enzimático do Citocromo P-450/metabolismo , Animais , Carcinógenos/metabolismo , Comunicação Celular/efeitos dos fármacos , Comunicação Celular/fisiologia , Linhagem Celular , Inibidores das Enzimas do Citocromo P-450 , Relação Dose-Resposta a Droga , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Junções Comunicantes/efeitos dos fármacos , Junções Comunicantes/metabolismo , Junções Comunicantes/fisiologia , Técnicas In Vitro , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/ultraestrutura , Masculino , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/enzimologia , Ratos , Ratos Wistar , Relação Estrutura-Atividade
7.
J Neurol ; 251(5): 525-8, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15164183

RESUMO

This paper presents an example of 18(th) century medical thinking. The author, Dr Georg Ernst Stahl (1659-1734) was the founder of the phlogiston theory in the field of chemistry, a medical professor, and a court physician in Saxony and Prussia. His description includes a definition of tremor, the internal and external causes of tremor, the types of tremor, the diagnostic and prognostic signs, and the treatment. From a present (contemporary) point of view, some compounds that were then used in treatment may have had a limited therapeutic effect on some kinds of tremor. Protopin has an anticholinergic and GABA-ergic effect, and rhoeadin (tetrahydrobenzazepin) may have had an effect similar to that of neuroleptics. Nevertheless, it is not clear whether the recommended quantity of these compounds was sufficient for a clinical effect. Most of the prescribed drugs could only have had a placebo effect.


Assuntos
Tremor/história , Benzofenantridinas , Alcaloides de Berberina/história , Alcaloides de Berberina/uso terapêutico , Antagonistas Colinérgicos/história , Antagonistas Colinérgicos/uso terapêutico , Alemanha , História do Século XVIII , Humanos , Tremor/terapia
8.
Phytochemistry ; 61(8): 967-70, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12453527

RESUMO

Dracophane, a novel structural derivative of metacyclophane, was isolated from the resin of Dracaena cinnabari Balf. The structure of this compound was determined by spectroscopic methods to be 3,12,21-trihydroxy-1,10,19-tris(4-hydroxyphenyl)-5,14,23-trimethoxy[3.3.3]metacyclophane.


Assuntos
Dracaena/química , Compostos Macrocíclicos , Fenóis/química , Fenóis/isolamento & purificação , Resinas Vegetais/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular
9.
Fitoterapia ; 75(2): 209-11, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15030927

RESUMO

The major constituents of fruits of Maclura pomifera are the prenylated isoflavones, osajin (1) and pomiferin (2). Since significant biological activities of extracts from the wood of M. pomifera were previously reported, the peroxynitrite scavenging activity, inhibition of lipid peroxidation, scavenging of DPPH and EROD activity of these two major substances were studied.


Assuntos
Benzopiranos/farmacologia , Sequestradores de Radicais Livres/farmacologia , Isoflavonas/farmacologia , Maclura , Fitoterapia , Benzopiranos/administração & dosagem , Benzopiranos/uso terapêutico , Compostos de Bifenilo , Citocromo P-450 CYP1A1/química , Sequestradores de Radicais Livres/administração & dosagem , Sequestradores de Radicais Livres/uso terapêutico , Frutas , Humanos , Isoflavonas/administração & dosagem , Isoflavonas/uso terapêutico , Peroxidação de Lipídeos/efeitos dos fármacos , Ácido Peroxinitroso/química , Picratos/química , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico
10.
Fitoterapia ; 82(2): 272-5, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20965235

RESUMO

A new isoflavanone 2',2,5-trimethoxy-6,7-methylenedioxyisoflavanone was isolated from the aerial parts of Iresine herbstii, together with isoflavone tlatlancuayin (2',5-dimethoxy-6,7-methylenedioxyisoflavone). The structure was identified using spectroscopic analysis. This is the first description of a methoxy group occurrence at position 2 of the isoflavanone skeleton. Both isolated compounds were tested for α-glucosidase inhibitory activity, but showed only a low effect compared to hyperoside.


Assuntos
Amaranthaceae/química , Isoflavonas/isolamento & purificação , Extratos Vegetais/química , Isoflavonas/farmacologia , Estrutura Molecular , Componentes Aéreos da Planta , Extratos Vegetais/isolamento & purificação , alfa-Glucosidases/metabolismo
11.
J Nat Prod ; 70(8): 1244-8, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17625893

RESUMO

Five geranylflavonoids, one prenylated flavonoid, and a simple flavanone were isolated from an ethanolic extract of Paulownia tomentosa fruit. Tomentodiplacol (1), 3'-O-methyl-5'-methoxydiplacol (2), 6-isopentenyl-3'-O-methyltaxifolin (3), and dihydrotricin (4) are reported from a natural source for the first time and 3'-O-methyldiplacone (6) for the first time from the genus Paulownia. The structures of the compounds were determined by mass spectrometry, including HRMS, and by 1D and 2D NMR spectroscopy. The cytotoxicity and DPPH (2,2-diphenyl-1-picrylhydrazyl)-quenching activity of some of these compounds were tested, with diplacone proving to be the best antioxidant, although the most cytotoxic compound.


Assuntos
Flavonoides/química , Flavonoides/isolamento & purificação , Scrophulariaceae/química , Compostos de Bifenilo , República Tcheca , Flavonoides/farmacologia , Frutas/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Picratos/farmacologia
12.
Acta Crystallogr C ; 61(Pt 6): o386-9, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15930692

RESUMO

The crystal structures of 2',4'-dihydroxy-3-methoxy-alpha,beta-dihydrochalcone, C16H16O4, and 2',4-dihydroxy-alpha,beta-dihydrochalcone, C15H14O3, have been determined. In both compounds, the structure consists of two nearly planar six-membered aromatic rings connected by a propanal chain, which is bent in the methoxy compound and almost straight in the other compound. In the crystal structures, the molecular units of both compounds are linked by O-H...O hydrogen bonds to form infinite one-dimensional chains. Hydrogen bonds and C-H...O contacts in the crystal structures were studied by topological analysis of charge density based on Hartree-Fock calculations. Almost all of the investigated C-H...O contacts should be characterized as weak hydrogen bonds.


Assuntos
Chalconas/química , Estrutura Molecular , Modelos Moleculares
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