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1.
Biomed Res Int ; 2019: 2692970, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30800665

RESUMO

In previous studies, Gentianella acuta (Michx.) Hulten was reported to contain xanthones, iridoids, terpenoids, and sterols and is mainly used to cure hepatitis, jaundice, fever, headache, and angina pectoris. In this study, we used bioassay guided fractionation to identify compounds from G. acuta and investigated their activity against hydrogen peroxide (H2O2)-induced apoptosis of H9c2 cells using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. The levels of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), and glutamate-cysteine ligase catalytic (GCLC) expression were assessed using quantitative real-time polymerase chain reaction (qRT-PCR). Protein expression was evaluated using western blot. The results showed that all four compounds had protective effects on H9c2 cells. The transcription levels of HO-1 and GCLC significantly increased in H9c2 cells pretreated with norswertianolin (1), swetrianolin (2), demethylbellidifolin (3), and bellidifolin (4). However, compared to the model group, the transcription levels of Nrf2 were not enhanced by pretreatment with compounds 1, 2, and 4. The protein expression levels of HO-1 and GCLC in H9c2 cells were greater than that in the H2O2-treated group, and the expression of Nrf2 was not significantly changed except by swetrianolin treatment; inhibitors can reverse the protective effect by ZnPP (15 µM), BSO (10 µM), and brusatol (10 µM). The results indicated that the four compounds isolated from G. acuta inhibited the oxidative injury induced by H2O2 by activating the Nrf2/ARE pathway in H9c2 cells and provide evidence that G. acuta may be a potential therapeutic agent for the treatment of cardiovascular diseases.


Assuntos
Gentianella/química , Peróxido de Hidrogênio/farmacologia , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Glutamato-Cisteína Ligase/metabolismo , Heme Oxigenase-1/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Transcrição Genética/efeitos dos fármacos , Xantenos/farmacologia , Xantonas/farmacologia
2.
Nat Prod Res ; 32(18): 2171-2177, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28868928

RESUMO

In the present study, two new xanthones, (5'S,8'S)-1,3,5,8-tetrahydroxyxanthone(7→2')-1,3,5,8-tetrahydroxy-5',6',7',8'-tetrahydroxanthone (1), 5-hydroxy-3,4,6-trimethoxyxanthone-1-O-ß-D-glucopyranoside (2), and eight known xanthones (3-10) were isolated from the whole plants of Gentianella acuta. Their structures were identified by the spectroscopic analyses (HR-ESI-MS, and 1D and 2D NMR). Meanwhile, cell-protective effects against H2O2-induced H9c2 cardiomyocyte injury and cytotoxic activities of compounds 1-10 were also determined.


Assuntos
Gentianella/química , Substâncias Protetoras/isolamento & purificação , Xantonas/isolamento & purificação , Morte Celular/efeitos dos fármacos , Linhagem Celular , Humanos , Peróxido de Hidrogênio , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Miocárdio/citologia , Extratos Vegetais/química , Substâncias Protetoras/farmacologia , Xantonas/química , Xantonas/farmacologia
3.
Molecules ; 22(8)2017 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-28783086

RESUMO

As a Mongolian native medicine and Ewenki folk medicinal plant, Gentianella acuta has been widely used for the treatment of diarrhea, hepatitis, arrhythmia, and coronary heart disease. In the course of investigating efficacy compounds to treat diarrhea using a mouse isolated intestine tissue model, we found 70% EtOH extract of G. acuta whole plants had an inhibitory effect on intestine contraction tension. Here, nineteen constituents, including five new compounds, named as gentiiridosides A (1), B (2), gentilignanoside A (3), (1R)-2,2,3-trimethyl-4-hydroxymethylcyclopent-3-ene-1-methyl-O-ß-d-glucopyranoside (4), and (3Z)-3-hexene-1,5-diol 1-O-α-l-arabinopyranosyl(1→6)-ß-d-glucopyranoside (5) were obtained from it. The structures of them were elucidated by chemical and spectroscopic methods. Furthermore, the inhibitory effects on motility of mouse isolated intestine tissue of the above mentioned compounds and other thirteen iridoid- and secoiridoid-type monoterpenes (7-10, 13-16, 18, 19, 21, 22, and 25) previously obtained in the plant were analyzed. As results, new compound 5, some secoiridoid-type monoterpenes 7, 10, 12-14, 16, and 17, as well as 7-O-9'-type lignans 31 and 32 displayed significant inhibitory effect on contraction tension at 40 µM.


Assuntos
Produtos Biológicos/química , Gentianella/química , Extratos Vegetais/química , Animais , Produtos Biológicos/farmacologia , Movimento Celular , Intestinos/citologia , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Camundongos , Estrutura Molecular , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia
4.
Biomed Pharmacother ; 93: 626-635, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28686977

RESUMO

Gentianella acuta (Michx.) Hulten is widely used for the treatment of arrhythmia and coronary heart disease in Ewenki Folk Medicinal Plants and Mongolian Medicine, popularly known as "Wenxincao" in China. To investigate the potential protective role of the xanthones from G. acuta against myocardial I/R injury in isolated rat heart and its possible related mechanism. The protective role of xanthones on myocardial I/R injury was studied on Langendorff apparatus. The hemodynamic parameters including the left ventricular developed pressure (LVDP), the maximum rate of up/down left intraventricular pressure (±dp/dtmax), coronary flow (CF) and heart rate (HR) were recorded during the perfusion. The results demonstrated that the xanthones from G. acuta treatment significantly improved myocardial function (LVDP, ±dp/dtmax and CF), increased the levels of superoxide dismutase (SOD) and catalase (CAT), succinate dehydrogenase (SDH), malate dehydrogenase (MDH), ATP and the ratio of glutathione and glutathione disulfide (GSH/GSSG), whereas suppressed the levels of Lactate dehydrogenase (LDH), creatine kinase (CK) and malondialdehyde (MDA). Furthermore, the xanthones upregulate the level of Bcl-2 protein and downregulate the level of Bax protein. These results indicated that xanthones from G. acuta exhibited cardioprotective effects on myocardial I/R injury through its activities of anti-oxidative effect and anti-apoptosis effect.


Assuntos
Cardiotônicos/farmacologia , Gentianella/química , Ventrículos do Coração/efeitos dos fármacos , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Xantonas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Catalase/metabolismo , Creatina Quinase/metabolismo , Glutationa/metabolismo , Ventrículos do Coração/metabolismo , L-Lactato Desidrogenase/metabolismo , Masculino , Malondialdeído/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Miocárdio/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo , Proteína X Associada a bcl-2/metabolismo
5.
Nat Prod Commun ; 12(1): 55-56, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30549824

RESUMO

Phytochemical study of Gentianella azurea (Bunge) Holub (Gentianaceae) collected in Buryatia Republic (Russian Federation) resulted in the isolation of twenty-one compounds including bellidifolin, bellidin, isobellidifolin, norswertianolin, isobellidifolin-8-O-ß-D-glucopyranoside, orientin, cynaroside, .cosmosiin, apigenin, 4'-O-caffeoylswertiamarin, swertiamarin-6'-O-ß-D-glucopyranoside and sweroside, firstly detected in this species. The extracts and individual compounds were shown to possess antioxidant and anticholinesterase potential.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Gentianella/química , Cromatografia Líquida de Alta Pressão , Extratos Vegetais/química , Federação Russa , Espectrofotometria Ultravioleta
6.
Fitoterapia ; 113: 164-9, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27514655

RESUMO

Five new compounds, gentixanthones A1 (1), A2 (2), and gentichromones A1-A3 (3-5), together with thirteen known xanthones (6-18) were obtained from the whole plants of Gentianella acuta (Michx.) Hulten. Their structures were elucidated by chemical and spectroscopic methods. Among them, compounds 6, 8, 13, 14, and 17 were obtained from Gentianella genus firstly, and 7, 12, 15, 16, and 18 were isolated from this plant for the first time. Meanwhile, inhibitory effects of 1-18 on motility of mouse isolated intestine tissue were determined. As results, xanthones 1, 2, 6, 7, 9, 10 and 14 were found to have significant reduce effect on intestine contraction tension, and structure-activity relationship was discussed.


Assuntos
Gentianella/química , Intestinos/efeitos dos fármacos , Peristaltismo/efeitos dos fármacos , Xantonas/farmacologia , Animais , Técnicas In Vitro , Camundongos , Estrutura Molecular , Relação Estrutura-Atividade , Xantonas/química
7.
J Nat Med ; 70(4): 780-8, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27306440

RESUMO

Two tetrahydroxanthones, 1,3,5S,8S-tetrahydroxy-5,6,7,8-tetrahydroxanthone (1) and 1,3,5R,8S-tetrahydroxy-5,6,7,8-tetrahydroxanthone (2), and six new tetrahydroxanthone glycosides, amarellins A-F (3-8), were isolated from the aerial parts of a Mongolian medicinal plant Gentianella amarella ssp. acuta (Gentianaceae). The structures of 1-8 were elucidated on the basis of spectroscopic analysis, chemical conversion, and ECD calculation. Amarellins A-C (3-5) were assigned as 8-O-ß-D-glucoside, 8-O-ß-D-xyloside, and 1-O-ß-D-glucoside of 1, respectively, while amarellins D-F (6-8) were elucidated to be 8-O-ß-D-xyloside, 1-O-ß-D-glucoside, and 3-O-ß-D-glucoside of 2, respectively.


Assuntos
Gentianella/química , Glucosídeos/isolamento & purificação , Glicosídeos/isolamento & purificação , Extratos Vegetais/química , Xantonas/isolamento & purificação , Gentianaceae/química , Glucosídeos/química , Glicosídeos/química , Estrutura Molecular , Mongólia , Componentes Aéreos da Planta , Plantas Medicinais/química , Xantonas/química
8.
Zhongguo Zhong Yao Za Zhi ; 41(12): 2280-2283, 2016 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-28901073

RESUMO

Twelve xanthones compounds were isolated from the ethanol extract of Gentianella acuta by means of reversed-phase preparative HPLC and various kinds of column chromatography including silica gel and ODS . Their structures were fully elucidated on the basis of MS, 1D and 2D-NMR data. The structures of xanthones were identified as 1, 7-dihydroxy-3-methoxyxanthone-7-O-ß-D-glucopyranoside (1), swertiapuniside (2), 1, 3, 8- trihydroxy -4, 5-dimethoxyxanthone-1-O-ß-D-glucopyranosyl(6→1)-O-ß-D-glucopyranoside (3), 1, 2, 8-trihydroxy-5, 6-dimethoxyxanthone-2-O-ß-D-glucopyranoside (4), 1, 3, 7, 8-tetrahydroxyxanthone-1-O-ß-D-glucopyranoside (5), 1, 3, 5, 8-tetrahydroxy-5, 6, 7, 8-tetrahydroxanthone (6), 1, 3, 5-thihydroxyxanthone (7),1, 3, 5, 8-tetrahydroxyxanthone (8), 1, 2, 8-trihydroxy-5, 6-dimethoxyxanthone (9), bellidifolin (10), mangiferin (11), swertianolin (12). Compounds 1-9 were isolated from Gentianella genus for the first time.


Assuntos
Gentianella/química , Extratos Vegetais/química , Xantonas/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação
9.
Zhongguo Zhong Yao Za Zhi ; 40(5): 804-6, 2015 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-26087537

RESUMO

Lomatogonium rotatum (L.) Fries, Gentianopsis barbata (Froel) Ma, and Gentianella acuta (Michx.) Hulten, the three kinds of Digeda-species Mongolian medicinal materials belonging to the family Gentianaceae, bad been widely used for the treatment of liver diseases. To analyze comparatively the content of swertiamarin and swertisin among these three kinds of Digeda-species Mongolian medicinal materials. HPLC method was applied for qualitative and quantitative analysis of swertiamarin and swertisin. The Phenomenex C18 (4.6 mm x 250 mm, 5 µm) was used, chromatographic methanol and water as mobile phase, the flow rate was 1.5 mL x min(-1) with UV detected at 237 nm, column oven temperature was 25 degrees C. Results showed that the contents of swertiamarin and swertisin were closely related the different species and producing areas. The content range of swertiamarin in L. rotatum from different habitats was 1.73% - 2.72%, 0.43% - 0.96% for the swertisin content; the content of swertiamarin in G. barbata from Alxa Left Banner was 0.38%, and the content of swertiamarin and swertisin in G. barbata from the others habitats and G. Acuta from different habitats were all detected qualitatively. The contents of swertiamarin and swertisin among these medicinal plants showed a significant difference due to the different species and producing areas. As a consequence, these medicinal plants should not be put together for clinical applications.


Assuntos
Apigenina/análise , Gentianaceae/química , Glucosídeos Iridoides/análise , Extratos Vegetais/análise , Pironas/análise , Cromatografia Líquida de Alta Pressão , Gentianaceae/classificação , Gentianella/química , Gentianella/classificação , Medicina Tradicional da Mongólia , Mongólia
10.
Bioorg Med Chem Lett ; 24(22): 5260-4, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25442320

RESUMO

A phytochemical investigation on crude extract of Gentianella azurea led to the isolation of ten new (1-10) and one known (11) secoiridoid glycosides. Their structures were unambiguously elucidated by analysis of 1D and 2D NMR. Compounds 2, 5 and 11 were found to inhibit nitric oxide (NO) production in RAW 264.7 macrophages with IC50 values of 52.78 ± 8.61, 0.69 ± 0.23 and 5.18 ± 1.33, respectively, while indomethacin, the positive control, showed an IC50 value of 1.25 ± 0.52 µM.


Assuntos
Anti-Inflamatórios/química , Gentianella/química , Glicosídeos Iridoides/química , Animais , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Linhagem Celular , Gentianella/metabolismo , Humanos , Glicosídeos Iridoides/isolamento & purificação , Glicosídeos Iridoides/farmacologia , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Espectroscopia de Ressonância Magnética , Camundongos , Conformação Molecular , Óxido Nítrico/metabolismo
11.
Zhong Yao Cai ; 37(5): 800-3, 2014 May.
Artigo em Chinês | MEDLINE | ID: mdl-25335286

RESUMO

OBJECTIVE: To study the lignans from the whole plant of Gentianella acuta. METHODS: The compounds were isolated by various chromatographic techniques and indentified by spectroscopic methods. RESULTS: Nine compounds were isolated and identified as (7R,8S) -dehydrodiconiferyl alcohol-4,9'-O-beta-D-glucopyranoside (1), alaschanisoside A (2), citrusin A (3), olivil-4'-O-beta-D-glucopyranoside (4), leptolepisol D (5), acanthoside D (6), (+) pinoresinol-4-O-beta-D-glucopyranoside (7), (+) 8-hydroxypinoresinol-4-O-beta-D-glucopyranoside (8), and (+) pinoresinol-8-O-beta-D-glucopyranoside (9). CONCLUSION: Compounds 1 - 9 are isolated from this plant for the first time, compounds 1 and 9 are isolated from Gentianella genus for the first time,and compounds 2, 3 and 5 - 8 are isolated from Gentianaceae family for the first time.


Assuntos
Gentianella/química , Lignanas/química , Plantas Medicinais/química , Alcaloides/química , Alcaloides/isolamento & purificação , Etanol/química , Glucosídeos/química , Glucosídeos/isolamento & purificação , Lignanas/isolamento & purificação , Espectroscopia de Ressonância Magnética
12.
Zhongguo Zhong Yao Za Zhi ; 39(4): 715-20, 2014 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-25204153

RESUMO

This study aims to establish a new method for quality evaluation of Gentianae Macrophyllae Radix by simultaneous determination of five iridoids (loganic acid, 6'-O-beta-D-glucopyranosylgentiopicroside, swertiamarin, gentiopicroside, sweroside), and to detect five iridoids in the root of eight species (Gentiana macrophylla, G. straminea, G. crassicaulis, G. dahurica, G. robusta, G. waltonii, G. lhassica, and G. tibetica). The separation was carried out on a Shiseido SPOLAR C18 (4.6 mm x 250 mm, 5 microm) column eluted with mobile phase of water containing 0.04% formic acid (A) and acetonitrile (B) in a gradient program. The flow rate was 0.8 mL x min(-1). The detect wavelength was set at 240 nm. The column temperature was kept at 30 degrees C. The volume of injection was 5 microL. The five iridoids were well separated with ideal linear correlations. The average recoveries were 97.35% - 106.23%. All the five iridoids were detected in the root of eight species. The contents of same species changed in a somewhat wider range. The contents in root of G. dahurica were lower than that in other species.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/análise , Gentianella/química , Glicosídeos Iridoides/análise , China
13.
J Nat Prod ; 77(5): 1201-9, 2014 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-24806310

RESUMO

Thirteen new dammarane-type triterpenoids (1-13) and four known analogues, gentirigenic acid (14) and the gentirigeosides A, B, and E (15-17), were isolated from Gentianella azurea. Their structures were elucidated by detailed analysis of the NMR, MS, and X-ray crystallographic data. This is the first report of dammarane-type triterpenoids in the Gentianella genus. In addition, the known structures of gentirigenic acid (14) and the gentirigeosides A, B, and E (15-17) were revised based on the X-ray diffraction analysis. Gentirigeoside A (15) was found to inhibit nitric oxide production in RAW 264.7 macrophages with an IC50 value of 6.6 ± 2.1 µM.


Assuntos
Medicamentos de Ervas Chinesas/isolamento & purificação , Gentianella/química , Triterpenos/isolamento & purificação , Animais , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos , Estrutura Molecular , Óxido Nítrico/biossíntese , Ressonância Magnética Nuclear Biomolecular , Triterpenos/química , Triterpenos/farmacologia
14.
Int J Food Sci Nutr ; 63(7): 802-12, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22475010

RESUMO

The dichloromethane (DCM), ethyl acetate (EtOAc), and methanol extracts from the leaves, roots, and flowers of the five species of Gentiana (Gentiana asclepiadea, Gentiana cruciata, Gentiana olivieri, Gentiana septemfida, and Gentiana verna) and Gentianella caucasea were investigated for their inhibitory activity against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) and antioxidant effect using 2,2-diphenyl-1-picrylhydrazyl radical scavenging, metal-chelation capacity, and ferric-reducing antioxidant power assays. Total phenol and flavonoid contents of the extracts were determined spectrophotometrically. The presence of some characteristic compounds found in Gentiana species (gentiopicroside, swertiamarin, isoorientin, isovitexin and vitexin) was analyzed in the extracts by thin layer chromatography. The flower DCM extract of G. verna exerted the highest inhibition against AChE (53.65 ± 1.03%), whereas the root EtOAc extract of G. cruciata was the most effective in BChE inhibition assay (50.72 ± 0.75%) at 100 µg ml⁻¹. The extracts of G. verna were also found to be more active in the antioxidant tests.


Assuntos
Antioxidantes/farmacologia , Inibidores da Colinesterase/farmacologia , Gentiana/química , Gentianella/química , Extratos Vegetais/farmacologia , Acetilcolinesterase/química , Acetilcolinesterase/metabolismo , Animais , Antioxidantes/química , Antioxidantes/isolamento & purificação , Butirilcolinesterase/química , Butirilcolinesterase/metabolismo , Inibidores da Colinesterase/química , Inibidores da Colinesterase/isolamento & purificação , Electrophorus/metabolismo , Etnofarmacologia , Flores/química , Flores/crescimento & desenvolvimento , Gentiana/crescimento & desenvolvimento , Gentianella/crescimento & desenvolvimento , Cavalos/metabolismo , Quelantes de Ferro/química , Quelantes de Ferro/isolamento & purificação , Quelantes de Ferro/farmacologia , Medicina Tradicional , Concentração Osmolar , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Folhas de Planta/crescimento & desenvolvimento , Raízes de Plantas/química , Raízes de Plantas/crescimento & desenvolvimento , Solventes/química , Especificidade da Espécie , Turquia
15.
Z Naturforsch C J Biosci ; 67(1-2): 29-38, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22486039

RESUMO

The infusion of the aerial parts of Gentianella multicaulis (Gillies ex Griseb.) Fabris (Gentianaceae), locally known as 'nencia', is used in San Juan Province, Argentina, as stomachic and as a bitter tonic against digestive and liver problems. The bioassay-guided isolation of G. multicaulis extracts and structural elucidation of the main compounds responsible for the antifungal and free radical scavenging activities were performed. The extracts had strong free radical scavenging effects in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay (45-93% at 10 microg/mL) and ferric-reducing antioxidant power (FRAP) assay at 200 microg/mL. Demethylbellidifolin (4) had high antioxidant activity in the DPPH and FRAP assay. The dermatophytes Microsporum gypseum, Trichophyton mentagrophytes, and T. rubrum were moderately inhibited by the different extracts (MIC values of 125-250 microg/mL). Demethylbellidifolin (4), bellidifolin (5), and isobellidifolin (6) showed an antifungal effect (MIC values of 50 microg/mL), while swerchirin (3) was less active with a MIC value of 100 microg/mL. In addition, oleanolic acid (1) and ursolic acid (2) were also isolated. These findings demonstrate that Gentianella multicaulis collected in the mountains of the Province of San Juan, Argentina, is an important source of compounds with antifungal and antioxidant activities.


Assuntos
Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Gentianella/química , Argentina , Cromatografia Líquida de Alta Pressão , Depuradores de Radicais Livres/farmacologia , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana
16.
Lima; s.n; 2011. [119] p. graf.
Tese em Espanhol | LILACS, MOSAICO - Saúde integrativa | ID: biblio-912220

RESUMO

El presente Trabajo de Tesis, intitulado, Contribución al Estudio Químico y Farmacológico de la Gentianella umbellata (G. Don) Fabris, tiene como objetivo contribuir al conocimiento sobre la composición química de la planta y su actividad farmacológica, entre ellas, la actividad hipoglicemiante que se le atribuye. Para su estudio, la planta se separa en dos partes : flores y, tallos y hojas; los extractos se obtuvieron consecutivamente con diclorometano y metanol. Se evalúan los extractos por CCD y HPLC; por los resultados preliminares se opta trabajar con el extracto metanólico. Este extracto es fraccionado por cromatografía líquida, mediante filtración en gel Sephadex LH-20 usando metanol como eluyente; se evalúan por CCD y se reúnen finalmente en 12 fracciones, de las cuales se estudian siete, que corresponden a fracciones que resuelven los componentes mayoritarios del extracto. Se han separado por métodos cromatográficos 11 compuestos, de los cuales se han identificado por métodos físico-químicos, cromatográficos y espectroscópicos: 1 flavonoide, Swertisina (4,5-dihidroxi-7-metoxi-6-gluco-flavona); 2 xantonas, Mangiferina (1,3,6,7-tetrahidroxi-2-C-glucosil-xantona), 8-O-glc-desmetilbellidifolina (1,3,5-trihidroxi-8-O-glucosil-xantona) y 1 triterpeno, ácido oleanólico (ác. 3b-hidroxiolean-12-en-28-oico). Así mismo se ha logrado separar y detectar; 3 secoiridoides, con valores de absorción UV a 235,2 ; 237,2 y 237,9 nm; 1 flavonoide, 3',4',5,7- tetrahidroxiflavona y 4 xantonas, compuestos D508/1, D51-III, I50 y H52a. El estudio químico se ha complementado con ensayos farmacológicos y pruebas de actividad antioxidante; como resultado el extracto metanólico mostró tener perfil como hipoglicemiante e hipolipemiante y las xantonas de la fracción metabólica (mangiferina y 8-O-glc-desmetilbellidifolina princi-palmente) muestran mejor actividad antioxidante.


Assuntos
Plantas Medicinais , Gentianella/química , Peru , Cromatografia
17.
Phytochem Anal ; 19(6): 514-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18546117

RESUMO

INTRODUCTION: A methanolic extract from Gentianella amarella ssp. acuta was shown to contain several xanthones exhibiting acetylcholinesterase inhibitory activity. These xanthones were difficult to separate by conventional LC techniques, which prevented the isolation of pure compounds in sufficient amounts to perform in-depth biological testing. OBJECTIVE: To develop a suitable preparative method for the separation of closely related xanthones. METHODOLOGY: The methanolic extract was first partitioned with solvents of increasing polarity, in order to separate glycosides from xanthone aglycones. High-speed countercurrent chromatography (HSCCC) methods were then optimised for the fractionation of both polar and non-polar extracts. RESULTS: The use of HSCCC enabled the separation of xanthones which co-eluted by HPLC. Ten closely related xanthones--three of which were isomeric--were successfully isolated by developing suitable solvent systems. All compounds were obtained in sufficient amounts to allow further biological assays (e.g. up to 250 mg), including even minor compounds that were not detectable by analytical HPLC. CONCLUSION: The orthogonality of HSCCC with HPLC and the absence of solid-phase supports enabled the detection, separation and preparative isolation of closely related compounds which were difficult to resolve by other techniques.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Distribuição Contracorrente/métodos , Gentianella/química , Xantonas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Solventes/química , Espectrofotometria Ultravioleta
18.
Planta Med ; 74(7): 736-40, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18446672

RESUMO

The aim of this study was to identify active principles of Gentianella austriaca responsible for the reduction of the incidence of micronuclei in irradiated lymphocytes in vitro. The radioprotective effects of ether (EF) and methanolic (MeF) fractions, water-soluble xanthones demethylbellidifolin (1), demethylbellidifolin 8-O-glucoside (2), bellidifolin 8-O-glucoside (3), and flavonoid swertisin (4) against chromosomal damage induced by gamma-rays were determined using the micronucleus test. EF and MeF showed better protection in treatment of human lymphocytes after gamma-irradiation than did isolated compounds. Among the isolated compounds, the effectiveness in reduction of the frequency of micronuclei followed the order 4>3>2>1. The anti-lipoperoxidant activity was in the order 2>4>1, while 3 slightly increased the level of malondialdehyde. In addition, the effectiveness in induction of apoptosis followed the order, 3>2>4, while 1 had no proapoptotic effect. These results suggest that the antioxidative properties of the polyphenols tested may contribute to the radioprotective effects of G. austriaca.


Assuntos
Flavonoides/isolamento & purificação , Raios gama , Gentianella/química , Linfócitos/efeitos da radiação , Fenóis/isolamento & purificação , Protetores contra Radiação/análise , Antioxidantes/análise , Apoptose/efeitos dos fármacos , Compostos de Bifenilo/química , Proliferação de Células/efeitos dos fármacos , Flavonoides/farmacologia , Humanos , Hidrazinas/química , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Malondialdeído/metabolismo , Testes para Micronúcleos , Fenóis/farmacologia , Picratos , Polifenóis , Protetores contra Radiação/farmacologia
19.
J Nat Prod ; 71(5): 895-7, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18336006

RESUMO

Two new xanthone glycosides, corymbiferin 3-O-beta-D-glucopyranoside (1) and swertiabisxanthone-I 8'-O-beta- d-glucopyranoside (2), were isolated from Gentianella amarella ssp. acuta, along with eight known xanthones: triptexanthoside C, veratriloside, corymbiferin 1-O-glucoside, swertianolin, norswertianolin, swertiabisxanthone-I, bellidin, and bellidifolin, four of them identified for the first time in G. amarella ssp. acuta. The isolation was conducted mainly by centrifugal partition chromatography, and the structures of the isolated compounds were established on the basis of spectrometric data including 2D NMR and mass spectrometry. Xanthones were weakly active against acetylcholinesterase (AChE), except triptexanthoside C, which inhibited AChE with an IC(50) of 13.8 +/- 1.6 microM. Some compounds were active against monoamine oxidases (MAO): bellidin and bellidifolin showed interesting inhibitory activity of MAO A, while swertianolin, the 8-O-glucopyranoside form of bellidifolin, gave 93.6% inhibition of MAO B activity at 10(-5) M.


Assuntos
Inibidores da Colinesterase/isolamento & purificação , Inibidores da Colinesterase/farmacologia , Gentianella/química , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Inibidores da Monoaminoxidase/isolamento & purificação , Inibidores da Monoaminoxidase/farmacologia , Plantas Medicinais/química , Xantonas/isolamento & purificação , Xantonas/farmacologia , Inibidores da Colinesterase/química , Glucosídeos , Glicosídeos/química , Estrutura Molecular , Mongólia , Inibidores da Monoaminoxidase/química , Ressonância Magnética Nuclear Biomolecular , Xantonas/química
20.
J Org Chem ; 71(11): 4237-45, 2006 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-16709067

RESUMO

Synthetic work toward the total synthesis of nitiol has culminated in the construction of two epimeric hydroxylated derivatives, the 1,22-dihydroxynitianes. Key stereodefining steps in the construction of the A-ring fragment (13) were the use of a siloxy-epoxide rearrangement reaction, a Pauson-Khand reaction, a Norrish 1 photochemical cleavage reaction, and a highly regio- and stereoselective hydrostannylation reaction of an ynoate. The stereochemistry of the synthetically challenging C-ring fragment (20) was established using an Ireland-Claisen reaction and a Grubbs ring-closing metathesis process as key steps. The 12-membered B-ring of the nitiane skeleton was constructed using a copper-promoted Stille cross-coupling and a Kishi-Hiyama-Nozaki carbonyl addition reaction. Unfortunately, the carbonyl addition reaction produced hydroxyl functionality that could not be selectively removed. Consequently, a synthesis of epimeric 1,22-dihydroxynitianes, which are compounds that are structural hybrids of two natural products, nitiol and variculanol, was completed.


Assuntos
Terpenos/síntese química , Gentianella/química , Estrutura Molecular
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