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1.
Planta Med ; 67(8): 737-42, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11731916

RESUMO

This research describes the identification of three new high molecular weight polysaccharide preparations isolated from food-grade microalgae that are potent activators of human monocytes/macrophages: "Immulina" from Spirulina platensis, "Immunon" from Aphanizomenon flos-aquae, and "Immurella" from Chlorella pyrenoidosa. These polysaccharides are structurally complex and have estimated molecular weights above ten million daltons. All three polysaccharides are highly water soluble and comprise between 0.5 % and 2.0 % of microalgal dry weight. Immunostimulatory activity was measured using a transcription factor-based bioassay for nuclear factor kappa B (NF-kappa B) activation in THP-1 human monocytes/macrophages. Using this system the EC(50) values for these microalgal polysaccharides are between 20 and 110 ng/ml (about 10pM). THP-1 activation was confirmed by measuring immune cytokine mRNA induction using reverse transcriptase-polymerase chain reaction (RT-PCR). Each polysaccharide substantially increased mRNA levels of interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha). These polysaccharides are between one hundred and one thousand times more active for in vitro monocyte activation than polysaccharide preparations that are currently used clinically for cancer immunotherapy.


Assuntos
Adjuvantes Imunológicos/isolamento & purificação , Chlorella/química , Cianobactérias/química , Preparações de Plantas/isolamento & purificação , Polissacarídeos/isolamento & purificação , Adjuvantes Imunológicos/química , Humanos , Interleucina-1/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Peso Molecular , Monócitos/efeitos dos fármacos , Monócitos/imunologia , NF-kappa B/imunologia , Preparações de Plantas/farmacologia , Polissacarídeos/química , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , Polissacarídeos Bacterianos , Fator de Necrose Tumoral alfa/metabolismo
2.
J Nat Prod ; 64(10): 1282-5, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11678651

RESUMO

Assay-guided fractionation of the ethanol extract of the twigs and leaves of Miconia myriantha yielded two new compounds, mattucinol-7-O-[4' ',6' '-O-(S)-hexahydroxydiphenoyl]-beta-D-glucopyranoside (1) and mattucinol-7-O-[4' ',6' '-di-O-galloyl]-beta-D-glucopyranoside (2), along with mattucinol-7-O-beta-D-glucopyranoside (3), ellagic acid (4), 3,3'-di-O-methyl ellagic acid-4-O-beta-D-xylopyranoside, and gallic acid. Complete (1)H and (13)C NMR assignments of compound 1, which possesses a hexahydroxydiphenoyl unit, were achieved using the HMBC technique optimized for small couplings to enhance the four-bond and two-bond H/C correlations. Compounds 1 and 4 showed inhibitory effects against Candida albicans secreted aspartic proteases, with IC(50) of 8.4 and 10.5 microM, respectively.


Assuntos
Glucosídeos/isolamento & purificação , Magnoliopsida/química , Plantas Medicinais/química , Inibidores de Proteases/isolamento & purificação , Ácido Aspártico Endopeptidases/antagonistas & inibidores , Candida albicans/efeitos dos fármacos , Candida albicans/enzimologia , Candida albicans/metabolismo , Cromatografia em Camada Fina , Dicroísmo Circular , Ácido Elágico/química , Ácido Elágico/farmacologia , Ácido Gálico/química , Ácido Gálico/farmacologia , Glucosídeos/química , Glucosídeos/farmacologia , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Conformação Molecular , Estrutura Molecular , Pepsina A/antagonistas & inibidores , Peru , Folhas de Planta/química , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Espectrofotometria Infravermelho , Espectroscopia de Infravermelho com Transformada de Fourier , Relação Estrutura-Atividade
3.
J Nat Prod ; 64(9): 1153-6, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11575947

RESUMO

A novel naphthopyrone derivative, named quinquangulone (1), has been isolated from Cassia quinquangulata, along with the known compounds quinquangulin (2) and its two glycosides (3 and 4), rubrofusarin (5) and its two glycosides (6 and 7), nor-rubrofusarin (8) and its 6-O-glucoside (9), and three stilbenes (10-12). The structure of quinquangulone was established by spectral interpretation as 5,9-dihydroxy-8-methoxy-2,9-dimethyl-6-oxo-4H,6H,9H-naphtho-[2,3-b]pyran-4-one. Reinvestigation of the NMR spectra of quinquangulin led to revision of its structure as 5,6-dihydroxy-8-methoxy-2,9-dimethyl-4H-naphtho[2,3-b]pyran-4-one (2a). The structures of two quinguangulin glycosides, 3 and 4, were also revised accordingly. Compound 2a exhibited activity against Staphylococcus aureus and methicillin-resistant S. aureus (MIC, 3.125 and 6.25 microg/mL, respectively).


Assuntos
Anti-Infecciosos/isolamento & purificação , Cassia/química , Glucosídeos/isolamento & purificação , Glicosídeos/isolamento & purificação , Naftóis/isolamento & purificação , Pironas/isolamento & purificação , Antibacterianos , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Aspergillus fumigatus/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Cryptococcus neoformans/efeitos dos fármacos , Resistência Microbiana a Medicamentos , Glucosídeos/química , Glucosídeos/farmacologia , Glicosídeos/química , Glicosídeos/farmacologia , Espectroscopia de Ressonância Magnética , Resistência a Meticilina , Testes de Sensibilidade Microbiana , Conformação Molecular , Estrutura Molecular , Complexo Mycobacterium avium/efeitos dos fármacos , Naftóis/química , Naftóis/farmacologia , Peru , Raízes de Plantas/química , Plantas , Plantas Medicinais/química , Pironas/química , Pironas/farmacologia , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Staphylococcus aureus/efeitos dos fármacos
4.
Phytochemistry ; 58(4): 627-9, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11576612

RESUMO

The indolopyridoquinazoline alkaloid, 3-hydoxyrutaecarpine, was isolated from Leptothyrsa sprucei, along with 8-methoxypsoralen, 5-methoxypsoralen, imperatorin, isoimperatorin, kaempferol 3-O-alpha-L-rhamnopyranoside, clematine and cnidioside B. The usefulness of the gradient 1H-15N HMBC NMR spectroscopy in the structure elucidation of 3-hydroxyrutaecarpine is noted.


Assuntos
Indóis/isolamento & purificação , Quinazolinas/isolamento & purificação , Rutaceae/química , Indóis/química , Estrutura Molecular , Quinazolinas/química , Análise Espectral
5.
J Nat Prod ; 64(8): 1001-5, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11520214

RESUMO

Four new alkaloids, nauclealines A (1) and B (2) and naucleosides A (3) and B (4), together with six known compounds, strictosamide (5), vincosamide (6), pumiloside (7), kelampayoside A, sitosterol, and sitosteryl beta-D-glucoside, were isolated from the bark of Nauclea orientalis. The structures of 1-4 were elucidated using 1D and 2D NMR spectral methods, including COSY, DEPT, HMQC, (13)C-(1)H HMBC, and (15)N-(1)H HMBC.


Assuntos
Alcaloides/química , Alcaloides/isolamento & purificação , Indóis/química , Indóis/isolamento & purificação , Plantas Medicinais/química , Rubiaceae/química , Cromatografia em Camada Fina , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Papua Nova Guiné , Caules de Planta/química , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Planta Med ; 67(2): 186-8, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11301876

RESUMO

Bioactivity-guided fractionation of an ethanolic extract of the leaves and twigs of Piper longicaudatum Trelease & Yunker (Piperaceae) resulted in the isolation of one new (1) and three known (2-4) dihydrochalcones. The known compounds are: 2',6'-dihydroxy-4'-methoxydihydrochalcone (2), 2',6',4-trihydroxy-4'-methoxydihydrochalcone (asebogenin) (3), and 2'-hydroxy-4'-methoxy-2'-[1-hydroxy-1-methylethyl]-2",3"-dihy- drofurano[4",5":5',6"]-3"-[2-hydroxy-5-methoxycarbonylphe- nyl]dihydrochalcone (piperaduncin B) (4). The new compound is 2'-hydroxy-4'-methoxy-2"-[2-hydroxy-5-methoxycarbonyl- phenyl]-furano[4",5":5',6']-dihydrochalcone (longicaudatin) (1). Compounds 1-4 were tested for antibacterial activity against S. aureus and methicillin-resistant S. aureus (MRSA); only compound 3 showed inhibitory activity (IC50 of 10 and 4.5 micrograms/ml, respectively).


Assuntos
Alcaloides/isolamento & purificação , Antibacterianos/isolamento & purificação , Chalcona/análogos & derivados , Chalcona/isolamento & purificação , Plantas Medicinais/química , Alcaloides/farmacologia , Antibacterianos/farmacologia , Chalcona/farmacologia , Chalconas , Estrutura Molecular , Folhas de Planta/química , Caules de Planta/química , Staphylococcus aureus/efeitos dos fármacos
7.
J Nat Prod ; 64(3): 345-7, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11277752

RESUMO

Resolution of racemic 2-benzyl-2-hydroxy-1-benzofuran-3(2H)-ones (auronols) and CD data of the ensuing enantiomers permit assessment of the absolute configuration at the single stereocenter.


Assuntos
Benzofuranos/química , Dicroísmo Circular , Cycadopsida/química , Rosales/química
8.
Planta Med ; 67(1): 87-9, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11270732

RESUMO

Five prenylated flavonoids, including one new natural product, were isolated from an ethanol extract of the leaves of Maclura tinctoria (L.) Gaud. The new compound has been characterized as 2',4',4,2''-tetrahydroxy-3'-[3''-methylbut-3''-enyl]chalcone (1). The known compounds were identified as 2',4',4-trihydroxy-3'-[3''-methylbut-3''-enyl]chalcone (isobavachalcone) (2), 4,2'-dihydroxy-2''-[1-hydroxy-1-methylethyl]-2'',3''-dihydrofurano[4'',5'':3',4']chalcone (bakuchalcone) (3), 4,4',5''-trihydroxy-6'',6''-dimethyldihydropyrano[2'',3'':5',6'']chalcone (bavachromanol) (4), and 5,7,3',4'-tetrahydroxy-6,8-diprenylisoflavone (6,8-diprenylorobol) (5). All the isolated compounds were evaluated against the AIDS-related opportunistic fungal pathogens, Candida albicans and Cryptococcus neoformans. Compound 2 was active against both yeasts.


Assuntos
Antifúngicos/isolamento & purificação , Candida albicans/efeitos dos fármacos , Chalcona/isolamento & purificação , Cryptococcus neoformans/efeitos dos fármacos , Rosales/química , Antifúngicos/química , Antifúngicos/farmacologia , Chalcona/química , Chalcona/farmacologia , Testes de Sensibilidade Microbiana , Estrutura Molecular , Análise Espectral
9.
Phytochemistry ; 53(8): 1033-7, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10820826

RESUMO

7-Caffeoylsedoheptulose has been isolated from the wood of Nyssa sylvatica, along with two ellagic acid derivatives and scopoletin. Its structure was established by chemical and spectral evidence.


Assuntos
Hexoses/isolamento & purificação , Árvores/química , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Hexoses/química
10.
J Nat Prod ; 62(9): 1341-2, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10514332

RESUMO

A new jujubogenin saponin was isolated from the stems of Colubrina retusa and identified as jujubogenin 3-O-alpha-L-arabinofuranosyl (1-->2)-[3-O-(trans)-p-coumaroyl-beta-D-glucopyranosyl (1-->3)]-alpha-L-arabinopyranoside (4) on the basis of chemical and spectroscopic data. The antimycobacterial activity expressed as minimum inhibitory concentration (MIC) for compound 4 was 10 microg/mL.


Assuntos
Antituberculosos/isolamento & purificação , Diterpenos/isolamento & purificação , Oligossacarídeos/isolamento & purificação , Triterpenos , Antituberculosos/química , Antituberculosos/farmacologia , Configuração de Carboidratos , Sequência de Carboidratos , Diterpenos/química , Diterpenos/farmacologia , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Complexo Mycobacterium avium/efeitos dos fármacos , Oligossacarídeos/química , Oligossacarídeos/farmacologia
12.
J Nat Prod ; 62(5): 674-7, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10346942

RESUMO

Antifungal assay-guided isolation of the 95% ethanol extract of the stems of Colubrina retusa yielded jujubogenin 3-O-alpha-L-arabinofuranosyl(1-->2)-[beta-D-glucopyranosyl (1-->3)]-alpha-L-arabinopyranoside (1), which showed modest growth-inhibitory effects against Candida albicans, Cryptococcus neoformans, and Aspergillus fumigatus (MICs, 50 microg/mL). In addition, two new minor saponins, jujubogenin 3-O-alpha-L-arabinofuranosyl(1-->2)-[2-O-(trans, cis)p-coumaroyl-beta-D-glucopyranosyl(1-->3)]-alpha-L-arabinopy ranosi de (2), and jujubogenin 3-O-(5-O-malonyl)-alpha-L-arabinofuranosyl (1-->2)-[beta-D-glucopyranosyl(1-->3)]-alpha-L-arabinopyranoside (3), were obtained. Saponin 2 was marginally active against only C. neoformans, with a MIC of 50 microg/mL, while 3 was inactive. NMR spectroscopy was used extensively for the structure determination of these compounds. The previously reported ambiguity of the NMR assignments of jujubogenin saponins for carbons -26 to -29 was clarified by a comprehensive analysis of the NMR spectra of 1.


Assuntos
Antifúngicos/farmacologia , Plantas/química , Saponinas/farmacologia , Antifúngicos/isolamento & purificação , Sequência de Carboidratos , Fungos/efeitos dos fármacos , Hidrólise , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Caules de Planta/química , Saponinas/isolamento & purificação
13.
J Nat Prod ; 62(5): 767-9, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10346966

RESUMO

Two new auronols, amaronols A (1) and B (2), were isolated from the bark of Pseudolarix amabilis, along with pseudolaric acid B (3), pseudolaric acid C (4), demethoxydeacetoxy-pseudolaric acid B (5), pseudolaric acid B-beta-D-glucoside (6), pseudolaric acid A-beta-D-glucoside (7), and myricetin (8). The structures of amaronols A and B were established by spectral data interpretation as 2,4,6-trihydroxy-2-[(3',4',5'-trihydroxyphenyl) methyl]-3(2H)-benzofuranone and 2,4,6-trihydroxy-2-[(3', 5'-dihydroxy-4'-methoxyphenyl) methyl]-3(2H)-benzofuranone, respectively. Antimicrobial testing results of the eight compounds indicated that only pseudolaric acid B was active against Candida albicans (MIC, 3.125 microg/mL; MFC, 6.25 microg/mL), while myricetin was marginally active against Trichophyton mentagrophytes (MIC, 50 microg/mL).


Assuntos
Antifúngicos/farmacologia , Benzofuranos/farmacologia , Cycadopsida/química , Medicamentos de Ervas Chinesas/química , Fenóis/farmacologia , Antifúngicos/química , Antifúngicos/isolamento & purificação , Benzofuranos/química , Benzofuranos/isolamento & purificação , Candida albicans/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Testes de Sensibilidade Microbiana , Fenóis/química , Fenóis/isolamento & purificação , Espectrofotometria Ultravioleta , Trichophyton/efeitos dos fármacos
17.
Planta Med ; 61(3): 290-1, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7617777

RESUMO

Evaluation of various methods of drying yew (Taxus) biomass was accomplished. The effect of the separation of the needles from clippings on the taxol content of Taxus plants was noted. Drying clippings intact preserves their taxol content.


Assuntos
Paclitaxel/análise , Folhas de Planta/química , Biomassa , Cromatografia Líquida de Alta Pressão , Dessecação/métodos , Plantas Medicinais , Árvores
18.
J Nat Prod ; 57(7): 1025-8, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7964784

RESUMO

The taxol content of dried Taxus biomass was monitored monthly for 15 months. Intact and finely ground biomass was stored at room temperature (22 degrees-24 degrees) as well as under refrigeration (2 degrees-4 degrees). In addition, intact fresh clippings stored under refrigeration in sealed plastic bags for up to 10 weeks were evaluated for changes in taxol content. Analysis indicates that properly dried Taxus clippings can be stored either intact or powdered at room temperature or under refrigeration with no apparent loss of taxol content. The taxol content in fresh intact clippings was also stable for at least 10 weeks when stored under refrigeration.


Assuntos
Paclitaxel/isolamento & purificação , Folhas de Planta/química , Plantas Medicinais/química , Biomassa , Cromatografia Líquida de Alta Pressão , Paclitaxel/análogos & derivados , Paclitaxel/química , Refrigeração
19.
Pharm Res ; 7(9): 923-7, 1990 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2235891

RESUMO

Microbial metabolism studies of the antimalarial drug arteether (1) have shown that arteether is metabolized to six new metabolites in addition to those previously reported (3). Large-scale fermentations with Cunninghamella elegans (ATCC 9245) and Streptomyces lavendulae (L-105) have resulted in the characterization of these metabolites primarily by two-dimensional nuclear magnetic resonance (2D-NMR) methods as 9 beta-hydroxyarteether (2), a ring rearrangement metabolite (3), 3 alpha-hydroxy-11-epi-deoxydihydroartemisinin (4), 9 alpha-hydroxyarteether (5), 2 alpha-hydroxyarteether (6), and 14-hydroxyarteether (7). Thermospray mass spectroscopy/high-performance liquid chromatographic analyses have shown that four of these metabolites (2, 5, 6, 7) are also present in rat liver microsome preparations.


Assuntos
Antimaláricos/metabolismo , Artemisininas , Sesquiterpenos/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Fermentação , Espectrometria de Massas , Microssomos Hepáticos/metabolismo , Mucorales/metabolismo , Ratos , Streptomyces/metabolismo
20.
J Anal Toxicol ; 14(5): 308-10, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2263066

RESUMO

Review of scientific literature shows that ingestion of poppy seed containing products can result in a positive urinalysis test for opiates. In many cases the amount of seeds ingested is unrealistically high or is not specified. This study is designed to correlate the amount of seeds ingested with the urinary concentration of total morphine as a function of time. Two males and two females were involved in all four protocols, which were separated by at least one week. Subjects ingested one, two, or three poppy seed rolls, each containing 2 g of Australian seeds (108 micrograms morphine/g seed) in three protocols. In the fourth protocol subjects ingested two rolls per day for four consecutive days. Urine specimens were collected for 48 h after ingestion, analyzed by RIA, EMIT, and TDx, and selected samples were confirmed by GC/MS. The data show that the highest concentrations of total morphine in urine were found 3-8 h after ingestion or in the first-void samples. Of the 264 samples collected, there were only 16 specimens that exceeded 300 ng/mL by any of the methods used for analysis with only three samples exceeding 400 ng/mL by GC/MS (406, 611, and 954 ng/mL). In all cases, the total opiates level was less than 150 ng/mL 24 h after ingestion. Following these studies, one of the subjects ingested a poppy seed cake containing 15 g seed obtained from a bakery which analyzed for 169 micrograms morphine/g seed. Urine specimens were collected over 48 h, and all specimens were analyzed by GC/MS.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Entorpecentes/urina , Papaver , Plantas Medicinais , Sementes , Detecção do Abuso de Substâncias , Codeína/urina , Reações Falso-Positivas , Feminino , Polarização de Fluorescência , Humanos , Técnicas Imunoenzimáticas , Masculino , Radioimunoensaio
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