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1.
Nat Prod Res ; 32(7): 767-772, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28778140

RESUMO

A new chalcone named as balanochalcone (1) together with eight known compounds, methyl caffeate (2), ß-hydroxydihydrochalcone (3), methyl gallate (4), dimethyl-6,9,10-trihydroxybenzo[kl]xanthene-1,2-dicarboxylate (5), p-coumaric acid (6), quercetin (7), scopoletin (8) and pinoresinol (9) have been isolated from the ethyl acetate extract of Vietnamese Balanophora laxiflora Hemsl. Their structures were characterised by IR, UV, HR-ESI-MS, 1D and 2D NMR and CD spectroscopies. Compounds 2 and 5 showed moderate cytotoxicity against four cancer cell lines, KB (a human epidermal carcinoma), MCF7 (human breast carcinoma), SK-LU-1 (human lung carcinoma) and HepG2 (hepatocellular carcinoma). In addition, compounds 1 and 5 showed moderate antioxidant activity.


Assuntos
Antineoplásicos Fitogênicos/química , Antioxidantes/farmacologia , Chalconas/química , Santalaceae/química , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/química , Linhagem Celular Tumoral , Chalconas/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Células Hep G2 , Humanos , Células MCF-7 , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray
2.
J Biol Chem ; 288(45): 32405-32413, 2013 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-24062307

RESUMO

Plants in the Santalaceae family, including the native cherry Exocarpos cupressiformis and sweet quandong Santalum acuminatum, accumulate ximenynic acid (trans-11-octadecen-9-ynoic acid) in their seed oil and conjugated polyacetylenic fatty acids in root tissue. Twelve full-length genes coding for microsomal Δ12 fatty acid desaturases (FADs) from the two Santalaceae species were identified by degenerate PCR. Phylogenetic analysis of the predicted amino acid sequences placed five Santalaceae FADs with Δ12 FADs, which include Arabidopsis thaliana FAD2. When expressed in yeast, the major activity of these genes was Δ12 desaturation of oleic acid, but unusual activities were also observed: i.e. Δ15 desaturation of linoleic acid as well as trans-Δ12 and trans-Δ11 desaturations of stearolic acid (9-octadecynoic acid). The trans-12-octadecen-9-ynoic acid product was also detected in quandong seed oil. The two other FAD groups (FADX and FADY) were present in both species; in a phylogenetic tree of microsomal FAD enzymes, FADX and FADY formed a unique clade, suggesting that are highly divergent. The FADX group enzymes had no detectable Δ12 FAD activity but instead catalyzed cis-Δ13 desaturation of stearolic acid when expressed in yeast. No products were detected for the FADY group when expressed recombinantly. Quantitative PCR analysis showed that the FADY genes were expressed in leaf rather than developing seed of the native cherry. FADs with promiscuous and unique activities have been identified in Santalaceae and explain the origin of some of the unusual lipids found in this plant family.


Assuntos
Ácidos Graxos Dessaturases/biossíntese , Ácidos Graxos Insaturados/biossíntese , Regulação Enzimológica da Expressão Gênica/fisiologia , Regulação da Expressão Gênica de Plantas/fisiologia , Folhas de Planta/enzimologia , Óleos de Plantas/metabolismo , Proteínas de Plantas/biossíntese , Santalaceae/enzimologia , Alcinos , Ácidos Graxos Dessaturases/genética , Ácidos Graxos Insaturados/genética , Folhas de Planta/genética , Proteínas de Plantas/genética , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Santalaceae/genética , Sementes/enzimologia , Sementes/genética , Sementes/imunologia
3.
Phytochemistry ; 74: 115-22, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22152976

RESUMO

Five unprecedented furan-2-carbonyl C-glycosides, scleropentasides A-E, and two phenolic diglycosides, 4-hydroxy-3-methoxybenzyl 4-O-ß-D-xylopyranosyl-(1→6)-ß-D-glucopyranoside and 2,6-dimethoxy-p-hydroquinone 1-O-ß-D-xylopyranosyl-(1→6)-ß-d-glucopyranoside, were isolated from leaves and twigs of Scleropyrum pentandrum together with potalioside B, luteolin 6-C-ß-D-glucopyranoside (isoorientin), apigenin 8-C-ß-D-glucopyranoside (vitexin), apigenin 6,8-di-C-ß-D-glucopyranoside (vicenin-2), apigenin 6-C-α-L-arabinopyranosyl-8-C-ß-D-glucopyranoside (isoschaftoside), apigenin 6-C-ß-D-glucopyranosyl-8-C-ß-D-xylopyranoside, adenosine and l-tryptophan. Structure elucidations of these compounds were based on analyses of chemical and spectroscopic data, including 1D and 2D NMR. In addition, the isolated compounds were evaluated for their radical scavenging activities using both DPPH and ORAC assays.


Assuntos
Antioxidantes/metabolismo , Glicosídeos/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Santalaceae/química , Compostos de Bifenilo/metabolismo , Glicosídeos/química , Glicosídeos/farmacologia , Estrutura Molecular , Picratos/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta , Caules de Planta
4.
Int J Syst Evol Microbiol ; 59(Pt 12): 3123-7, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19643877

RESUMO

An endophytic actinomycete, strain YIM 65070(T), was isolated from surface-sterilized tissue of Osyris wightiana Wall. ex Wight collected from Yunnan province, south-west China, and characterized by using a polyphasic approach. Strain YIM 65070(T) had morphological and chemotaxonomic markers that were consistent with its classification in the genus Herbidospora. Phylogenetic analysis based on almost complete 16S rRNA gene sequences indicated that strain YIM 65070(T) was phylogenetically very closely related to Herbidospora cretacea IFO 15474(T). DNA-DNA hybridization experiments confirmed the separate genomic status of strains YIM 65070(T) and H. cretacea DSM 44071(T). Moreover, strain YIM 65070(T) could be distinguished from H. cretacea DSM 44071(T) by differences in several phenotypic characteristics such as tolerance to NaCl, degradation activity, utilization of sole carbon and nitrogen sources and the cellular fatty acid contents. On the basis of phenotypic and phylogenetic evidence, strain YIM 65070(T) was identified as a novel species of the genus Herbidospora, for which the name Herbidospora osyris sp. nov. is proposed, with YIM 65070(T) (=CCTCC AA 208019(T)=DSM 45214(T)) as the type strain.


Assuntos
Actinomycetales/classificação , Actinomycetales/isolamento & purificação , Santalaceae/microbiologia , Actinomycetales/genética , Actinomycetales/metabolismo , China , DNA Bacteriano/genética , DNA Ribossômico/genética , Ácidos Graxos/metabolismo , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética
5.
Rev. biol. trop ; Rev. biol. trop;57(1/2): 283-292, March-June 2009. graf, tab
Artigo em Espanhol | LILACS | ID: lil-637718

RESUMO

Pollen dispersion and reproductive success of four tree species of a xerophytic forest from Argentina. The "talares" in eastern Buenos Aires province, Argentina, are coastal xerophitic forests structured by few arboreal species surrounded by a lower and moister soil matrix. We studied the reproductive parameters of the most representative arboreal species (Celtis tala, Scutia buxifolia, Jodina rhombifolia,and Schinus longifolia). Pollen dispersion was studied through floral visitor traps (biotic dispersion) and using gravimetric pollen collectors (abiotic dispersion). The reproductive success (fruit formation rate) of the focal species was studied by enclosing flowers with different mesh bags. The reproductive system varied among the different species. C. tala was anemophilous and selfcompatible. S. buxifolia was entomophilous and floral visitors dependant. J. rhombifolia was entomophylous, although spontaneous autogamy could favor reproduction in the absence of pollinators. Lastly, S. longifolia could be an ambophilous species (pollinated by insects and by the wind). This dual system may be the result of system flexibility mechanism or an evolutionary transition. Rev. Biol. Trop. 57 (1-2): 283-292. Epub 2009 June 30.


Los "talares" del E de la provincia de Buenos Aires son bosques xerófitos costeros estructurados por pocas especies arbóreas rodeados de una matriz de suelos más bajos y húmedos. Estudiamos los parámetros reproductivos de las especies arbóreas más representativas (Celtis tala, Scutia buxifolia, Jodina rhombifolia y Schinus longifolia). La dispersión polínica fue estudiada a través de trampas para visitantes florales (dispersión biótica) y utilizando recolectores gravimétricos de polen (dispersión abiótica). El éxito reproductivo (tasa de formación de frutos) de las especies focales fue estudiado a través de embolsado de flores con bolsas de distintos tipos de malla. El sistema reproductivo varió entre las especies. C. tala resultó anemófila y autocompatible, S. buxifolia fue entomófila y dependiente de los visitantes florales. J. rhombifolia fue una especie entomófila, aunque la autogamia espontánea podría favorecer al aseguramiento reproductivo en caso de falta de polinizadores. Finalmente, S. longifolia podría ser una especie ambófila (polinizada por insectos y por el viento). Este sistema dual podría ser el resultado de un mecanismo de flexibilidad del sistema de polinización o una transición evolutiva.


Assuntos
Animais , Frutas/crescimento & desenvolvimento , Pólen/crescimento & desenvolvimento , Polinização/fisiologia , Árvores/fisiologia , Argentina , Anacardiaceae/classificação , Anacardiaceae/crescimento & desenvolvimento , Anacardiaceae/fisiologia , Ecossistema , Insetos/fisiologia , Reprodução/fisiologia , Rhamnaceae/classificação , Rhamnaceae/crescimento & desenvolvimento , Rhamnaceae/fisiologia , Santalaceae/classificação , Santalaceae/crescimento & desenvolvimento , Santalaceae/fisiologia , Árvores/classificação , Árvores/crescimento & desenvolvimento , Ulmaceae/classificação , Ulmaceae/crescimento & desenvolvimento , Ulmaceae/fisiologia
6.
Horiz. méd. (Impresa) ; 9(1): 36-39, ene.-jun. 2009.
Artigo em Espanhol | LILACS, LIPECS | ID: lil-676654

RESUMO

La peroxidación lipídica es un mecanismo deletéreo para las células, causada por los radicales libres presentes en el envejecimiento celular. Existen plantas con metabolitos secundarios con capacidad antioxidante. Quinchamalium procumbens es una hierba perenne de 15 a 25 centímetros de inflorescencia, de color amarillo, con 12 especies sudamericanas y nativa del Perú, distribuida en la cordillera de los Andes entre los 3500 a 4000 msnm. Estudios previos mostraron la presencia de moléculas antioxidantes como los flavonoides. El objetivo del presente trabajo es evaluar la capacidad antioxidante de los metabolitos de Quinchamalium procumbens e identificar los posibles agentes antioxidantes. Materiales y métodos: Se midió el efecto del potencial reductor del extracto etanólico de Quinchamalium procumbens por la reacción colorimétrica entre el malondialdeído y el ácido tiobarbitúrico 535 nm. Los metabolitos secundarios fueron identificados por cromatografía en capa fina, usando reactivos para revelaciones generales, terpenoides, esteroides y fenolitos. Resultados: Se obtuvo un 50% de inhibición de radicales libres. Los principales agentes reductores identificados por cromatografía fueron los flavonoides. Discusión y conclusión: El 50% de inhibición de radicales libres en neuroblastos, frente a un antioxidante de referencia como el alfa tocoferol, con un valor de 54.2% de inhibición, posiblemente debido a los flavonoides, muestra un gran poder reductor del extracto etanólico total de la planta estudiada, siendo este un estudio previo a los futuros donde se evalúe la mayor concentración de metabolitos reductores por partes de la planta.


Lipidical oxidation is a deleterious mechanism against cells caused by free radicals in cellÆs age. Quinchamalium procumbens is a plant with 15 to 25 cm of size, yellow flowers, 12 species in South America and it is original from Peru. Previous studies showed the presence of reductors molecules. The objective of the study is to evaluate the antioxidant capacity and identify the possible antioxidant metabolites. Material and methods: The potential redactor effect of Quinchamalium procumbens was measured using a colorimetric method to identify the reaction between malondialdeido and tiobarbituric acid. The secundary metabolites were identified by cromatography. Results: The inhibition of free radicals was 50%. The principal reductor agent identified were flavonoides. Discussion and conclusion: The 50% of inhibition obtained and compared with a referencial antioxidante alfa tocoferol with a value of 54.2% showed an important reductor power in ethanolic extract in the studied plant.


Assuntos
Antioxidantes , Flavonoides , Santalaceae
7.
Expert Opin Investig Drugs ; 17(9): 1353-64, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18694368

RESUMO

BACKGROUND: Botanicals and herbal combinations are among the most common complementary and alternative medicine (CAM) approaches used by cancer patients both for cancer treatment and management of cancer symptoms. Despite their widespread use, however, the safety and efficacy of many botanicals has not been established in controlled clinical trials. OBJECTIVES: This article reviews the published evidence for the safety and clinical benefit of botanicals used in the treatment of cancer and cancer symptom management and describes the continuing clinical trials of botanicals with applications in oncology. METHODS: Literature searches were conducted in PubMed, EMBASE, Cochrane Clinical Trials databases, Pharmaprojects and CRISP (Computer Retrieval of Information on Scientific Projects) clinical trials databases. CONCLUSION: A number of botanicals have shown promise for cancer symptom management but need further study. A limited number of multi-agent nutritional supplement approaches are being explored in clinical trials. Botanical immunomodulators and botanical products shown to affect pathways of angiogenesis, apoptosis and cell signaling in vitro have stimulated research interest and may broaden the range of available cancer treatments.


Assuntos
Neoplasias/tratamento farmacológico , Fitoterapia , Agaricales/química , Animais , Antineoplásicos/uso terapêutico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Humanos , Neoplasias/patologia , Santalaceae/química
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