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1.
Nat Prod Res ; 35(23): 5459-5464, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32594773

RESUMO

Cordyceps sinensis is a traditional Chinese medicine with various biological activities. With its limited natural supply, cultured C. militaris has become the major alternative source, and the culture conditions may affect the chemical compositions. To improve the production of chemical ingredients, C. militaris was cultured with three different media, including rice only, rice plus 3% tea leaves, and rice plus 3% droppings of Andraca theae. The fractions of dried C. militaris cultured with rice were chromatographic separated to afford ten compounds: phenylalanine, dimerumic acid, nicotinic acid, tryptophan, N6-(2-hydroxyethyl)-adenosine, uracil, uridine, cordycepin, ergosterol, and mannitol. Of these, in the cultured medium of rice plus 3% Andraca droppings, the amount of one major compound cordycepin is about two folds than the highest reported data, and dimerumic acid and N6-(2-hydroxyethyl)-adenosine were isolated for the first time from this species.[Figure: see text].


Assuntos
Cordyceps , Adenosina , Desoxiadenosinas , Manitol
2.
J Food Drug Anal ; 27(4): 897-905, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31590761

RESUMO

The seed of Hyptis suaveolens, commonly known as wild flour ball (san fen yuan) in Taiwan, serves as a main refreshing drink substance in several regions. This study investigated firstly its secondary metabolites, leading to the isolation of five major caffeoylquinic acid derivatives (1-5) from the ethanol extract. In addition, ten minors, including three caffeoylquinic acid derivatives (12-14), were characterized via assistance of HPLC-SPE-NMR. Of these isolates, sodium 4,5-dicaffeoylquinate (2) and methyl 3,5-dicaffeoylquinate (4) showed moderate inhibitory activity against xanthine oxidase with the respective IC50 values of 69.4 µM and 92.1 µM (c.f. allopurinol IC50 28.4 µM). Quantitative HPLC analysis of the EtOH extract indicates the content of sodium 3,5-dicaffeoylquinate (1) and sodium 4,5-dicaffeoylquinate (2) to be 0.1% and 0.08% (w/w, dry seed), respectively. This study not only discloses the bioactive constituents, but also demonstrates the potential of H. suaveolens seed as an antihyperuricemic nutraceutical.


Assuntos
Suplementos Nutricionais/análise , Hiperuricemia/tratamento farmacológico , Hyptis/química , Extratos Vegetais/uso terapêutico , Ácido Quínico/análogos & derivados , Sementes/química , Cromatografia Líquida de Alta Pressão , Humanos , Hiperuricemia/metabolismo , Espectroscopia de Ressonância Magnética , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Ácido Quínico/química , Ácido Quínico/isolamento & purificação , Ácido Quínico/uso terapêutico , Taiwan
3.
Fitoterapia ; 139: 104376, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31629048

RESUMO

Ten compounds were isolated from the root bark of Bombax malabarica, including two new compounds, bombamalin (1) and 3,4,5-trimethoxyphenol-1-[ß-xylopyranosyl-(1 → 2)]-ß-glucopyranoside (3), and shorealactone (4), a rare dehydroascorbic acid fused l-ε-viniferin. Compound 1 is an unusual bissesquiterpene, containing a 1,4-dioxene ring formed by fusing isohemigossypol with ent-cadinen-2-one. Their structures were elucidated by extensive spectroscopic analysis. This chemical reinvestigation is of value for chemotaxonomy of the Bombax genus, in particular the finding of the unusual 1 and rare 4. Among the isolates, shorealactone (4), l-epicatechin 5-O-ß-D-xyloside (5), and 2-C-[ß-D-apiosyl-(1 → 6)]- ß-D-glucosyl]-1,3,6-trihydroxy-7-methoxyxanthone (6) displayed some inhibition against α-glucosidase with IC50 values of 224, 345, and 285 µM, respectively.


Assuntos
Bombax/química , Compostos Fitoquímicos/isolamento & purificação , Casca de Planta/química , Raízes de Plantas/química , Inibidores de Glicosídeo Hidrolases , Sesquiterpenos/isolamento & purificação , Taiwan
4.
J Food Drug Anal ; 26(2): 557-564, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29567224

RESUMO

Bioassay guided fractionation and separation of the EtOH extract of the kernels of Palaquium formosanum against PC-3 cells via Sephadex LH-20 and reverse phase C-18 columns led to the isolation of 13 protobassic saponins. One of these saponins is new and was characterized as 3‴-O-rhamnopyranosyl-arganin C, a bisdesmoside of 16α-hydroxyprotobassic acid at the C-3 and C-28 positions. The structures of these compounds were determined on the basis of 1D NMR (1H, 13C), 2D NMR (1H-1H COSY, HSQC, HMBC, and NOESY), and selectively excited 1D TOCSY spectroscopic analyses and MS data, and comparison with literature data. Bioassay of these compounds and five additional compounds, isolated from Planchonella obovata leaf, against PC-3 prostate cancer cells indicated arganin C to be the most potent one with the IC50 value of 13.8 µM. Some structure and activity relationships were also drawn.


Assuntos
Palaquium/química , Extratos Vegetais/farmacologia , Saponinas/farmacologia , Triterpenos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Saponinas/química , Saponinas/isolamento & purificação , Sementes/química , Triterpenos/química , Triterpenos/isolamento & purificação
5.
Nat Prod Commun ; 11(8): 1079-1080, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30725561

RESUMO

Bioassay guided fractionation against a-glucosidase and separation of the ethanolic extract of Pasania formosana leaf by chromatographic methods led to the isolation of a novel secocycloartane triterpene. This compound, named pasasecocycloartenoic acid, was elucidated as 21,24(R)-epoxy-25-hydroty-3;4- secocycloart-4(28)-en-3-oic acid through analysis of 1D and 2D NMR spectra and on the basis of HRESIMS data. The compound showed weak activity against α-glucosidase, but its poor solubility hampered the bioassay.


Assuntos
Fagaceae/química , Folhas de Planta/química , Triterpenos/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Extratos Vegetais/química
6.
Nat Prod Commun ; 10(6): 891-3, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26197510

RESUMO

Bioassay guided fractionation and separation of the EtOH extract of Annona glabra leaf against acetylcholinesterse led to the characterization of 15 alkaloids. Among them, (-)-actinodaphnine (2) and (-)-(6aS,7R)-7-hydroxyactinodaphnine (9) are new aporphines, although (+)-2 and (±)-2 have been found in several plants. Their structures were established by spectroscopic analysis. (-)-Anolobine (5) and (-)-roemeroline (8) showed moderate inhibitory activity against eel acetylcholinesterase with IC50 values of 22.4 and 26.3 µM, respectively.


Assuntos
Alcaloides/química , Annona/química , Inibidores Enzimáticos/química , Extratos Vegetais/química , Acetilcolinesterase/análise , Alcaloides/isolamento & purificação , Inibidores Enzimáticos/isolamento & purificação , Estrutura Molecular , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química
7.
Nat Prod Commun ; 10(1): 63-6, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25920221

RESUMO

Chemical investigation of the n-BuOH-soluble fraction of the EtOH extract of the aerial part of Curcuma longa led to the isolation of 11 flavonol glycosides and one dihydroflavonol glucoside (1) via chromatography over Sephadex LH-20 and Lobar RP-18 columns. Although they are known, the 1H and 13C NMR data recorded in CD3OD rather than the common DMSO-d6 are doubly checked via extensive 2D NMR spectroscopic analyses, leading to some revisions of the reported data, especially for the glycon part.


Assuntos
Curcuma/química , Flavonoides/química , Glicosídeos/química , Espectroscopia de Ressonância Magnética , Folhas de Planta/química , Plantas Medicinais/química
8.
Phytochemistry ; 101: 121-7, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24559911

RESUMO

The active fraction from the EtOH extract of Hyptis rhomboides against xanthine oxidase was identified by use of an HPLC microfractionation-centrifugal vacuum evaporation-bioassay hyphenated technique. Scale-up separation of the active subfractions using semi-preparative RP-HPLC provided 13 phenylpropanoid compounds, including O-styrenylneolignans, hyprhombins A-C, epihyprhombin B, and hyprhombin B methyl ester, and O-caffeoylnorneolignans, hyprhombins D and E. All of these compounds shared a common 1,4-benzodioxane skeleton, as established by spectroscopic analyses. Hyprhombin C and epihyprhombin B exhibited better anti-xanthine oxidase activity than allopurinol, with IC50 values of 0.6 and 2.0 µM, respectively.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Inibidores Enzimáticos/farmacologia , Hyptis/química , Lignanas/farmacologia , Xantina Oxidase/antagonistas & inibidores , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/isolamento & purificação , Inibidores Enzimáticos/isolamento & purificação , Concentração Inibidora 50 , Lignanas/isolamento & purificação , Estrutura Molecular , Componentes Aéreos da Planta/química
9.
Phytochemistry ; 74: 206-11, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22169017

RESUMO

Triterpenoids, 1-3, 8 and 9, along with 24 known compounds were isolated from leaves and twigs of Fagus hayatae. Of these, compound 1, 1,10-seco-3ß,10α,23-trihydroxyolean-12-ene-1,28-dioic acid 1,23-lactone, possesses a hitherto unknown 1,10-seco-oleanane skeleton. In addition, 2,3-seco-20(29)-lupene-2,3-dioic acid (16), previously described as a synthetic product, is now established as a plant natural product; the neolignan-9'-O-rhamnoside 19 is also characterized herein. Their structures were deduced mainly by 1D and 2D NMR spectroscopic analyses. Seven of these compounds possess moderate inhibitory activity against α-glucosidase type IV (Bacillus stearothermophilus).


Assuntos
Inibidores Enzimáticos/farmacologia , Fagus/química , Inibidores de Glicosídeo Hidrolases , Extratos Vegetais/farmacologia , Triterpenos/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Geobacillus stearothermophilus/metabolismo , Estrutura Molecular , Extratos Vegetais/química , Folhas de Planta , Caules de Planta , Triterpenos/química , Triterpenos/isolamento & purificação
10.
J Nat Prod ; 73(10): 1632-5, 2010 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-20828184

RESUMO

The active fraction of the EtOH extract of the stem of Annona glabra against acetylcholinesterase (AChE) was analyzed by combining HPLC microfractionation with a bioassay. The analytical-scale sample was fractionated by HPLC-DAD into 96-well microplates, which, after evaporation, were assayed against AChE. The active subfractions were scaled up by separation over semipreparative HPLC to give 20 compounds. Four of these, (7S,14S)-(-)-N-methyl-10-O-demethylxylopinine salt (3), S-(-)-7,8-didehydro-10-O-demethylxylopininium salt (10), S-(-)-7,8-didehydrocorydalminium salt (11), and 5-O-methylmarcanine D (17), were assigned as new natural products. In addition, compounds 10 and 11 represent the first natural occurrence of 7,8-didehydroprotoberberines. Compound 3, pseudocolumbamine (12), palmatine (15), and pseudopalmatine (16) showed anti-AChE IC50 values of 8.4, 5.0, 0.4, and 1.8 µM, respectively.


Assuntos
Acetilcolinesterase/efeitos dos fármacos , Alcaloides de Berberina/isolamento & purificação , Alcaloides de Berberina/farmacologia , Inibidores da Colinesterase/isolamento & purificação , Inibidores da Colinesterase/farmacologia , Annona , Alcaloides de Berberina/química , Inibidores da Colinesterase/química , Cromatografia Líquida de Alta Pressão , Concentração Inibidora 50 , Estrutura Molecular
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