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1.
Nat Prod Res ; : 1-8, 2024 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-38613238

RESUMEN

The techniques LC-UV-BPSU and LC-UV-SPE/NMR were applied for the first time in the analysis of açai berry (Euterpe oleracea Mart.) pulp extracts. Those techniques allowed the identification of twenty-three metabolites: Valine (1), citric acid (2), tachioside (3), isotachioside (4), α-guaiacylglycerol (5), syringylglycerol (6), uridine (7), adenosine (8), dimethoxy-1,4-benzoquinone (9), koaburaside (10), protocatechuic acid (11), eurycorymboside B (12), 7',8'-dihydroxy-dihydrodehydroconiferyl alcohol-9-O-ß-D-glucopyranoside (13), orientin (14), homoorientin (15), dihydrokaempferol-3-glucoside (16), isolariciresinol-9'-O-ß-D-glucopyranoside (17), 5'-methoxyisolariciresinol-9'-O-ß-D-glucopyranoside (18), cyanidin-3-O-glucoside (19), cyandin-3-O-rutenoside (20), 9,12-octadecadienoic acid (Z,Z)-2-hydroxy-1-(hydroxymethyl) ethyl ester (21), linolenic acid (22), and 1,2-di-O-α-linolenoyl-3-O-ß-D-galactopyranosyl-sn-glycerol (23). In this plant, compounds 3, 4, 5, 6, 8, 10, 12, 17, 18, 21, and 23 are reported for the first time. All the structures were determined through extensive analyses of 1D and 2D NMR data, mass spectrometry, and comparison with published data. This methodology has proven to be an efficient alternative to the analysis of complex extracts containing a large variety of compounds.

2.
Bioorg Chem ; 95: 103560, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31918399

RESUMEN

Candida glabrata, the most common non-albicans Candida species and one of the primary causes of candidemia, exhibits decreased susceptibility to azoles and more recently to echinocandins. Polyalthic acid 1, a furan diterpene, has been shown promising biological potential and in this study ent-polyalthic acid derivatives with antifungal activity against Candida glabrata were produced by microbial transformation. Incubation of 1 with Aspergillus brasiliensis afforded two known (compounds 5 and 10) and eight new derivatives (compounds 2-4, 6-9 and 11). The most common reaction was hydroxylation, but isomerization of the double bond and acetylation were also detected. None of the tested compounds showed cytotoxicity against HeLa, MCF-7 and MCF-10A cell lines showing IC50 values ranging from 62.6 µM to > 500 µM. Compounds 1, 5, 6, 8 and 11 showed fungistatic effects (ranging from 34.1 µM to 39.5 µM) on C. glabrata at lower concentrations than fluconazole (163.2 µM). Compounds 1, 6 and 8 were more potent fungicides (ranging from 79.0 to 143.6 µM) than fluconazole, which showed fungicidal effect at concentrations higher than 163.2 µM. These results suggest that ent-polyalthic acid and some of its derivatives could be used as lead compounds to develop new antifungal agents.


Asunto(s)
Antifúngicos/farmacología , Aspergillus/metabolismo , Candida glabrata/efectos de los fármacos , Diterpenos/farmacología , Biotransformación , Línea Celular Tumoral , Diterpenos/metabolismo , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Pruebas de Sensibilidad Microbiana , Microsomas Hepáticos/metabolismo
3.
Front Chem ; 7: 762, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31781544

RESUMEN

Lawsone itself exhibits interesting biological activities, and its complexation with a metal center can improve the potency. In this context a cytotoxic Ru-complex, [Ru(law)(dppb)(bipy)] (law = lawsone, dppb = 1,4-bis(diphenylphosphino)butane and bipy = 2,2'-bipyridine), named as CBLAU, was prepared as reported. In this work, NMR binding-target studies were performed to bring to light the most accessible interaction sites of this Ru-complex toward Calf-Thymus DNA (CT-DNA, used as a model), in a similar approach used for other metallic complexes with anti-cancer activity, such as cisplatin and carboplatin. Advanced and robust NMR binding-target studies, among them Saturation Transfer Difference (STD)-NMR and longitudinal relaxometry (T1), were explored. The 1H and 31P -NMR data indicate that the structure of Ru-complex remains preserved in the presence of CT-DNA, and some linewidth broadening is also observed for all the signals, pointing out some interaction. Looking at the binding efficiency, the T1 values are highly influenced by the formation of the CBLAU-DNA adduct, decreasing from 11.4 s (without DNA) to 1.4 s (with DNA), where the difference is bigger for the lawsone protons. Besides, the STD-NMR titration experiments revealed a stronger interaction (KD = 5.9 mM) for CBLAU-DNA in comparison to non-complexed lawsone-DNA (KD = 34.0 mM). The epitope map, obtained by STD-NMR, shows that aromatic protons from the complexed lawsone exhibits higher saturation transfer, in comparison to other Ru-ligands (DPPB and bipy), suggesting the supramolecular contact with CT-DNA takes place by the lawsone face of the Ru-complex, possibly by a spatial π-π stacking involving π-bonds on nucleic acids segments of the DNA chain and the naphthoquinone group.

4.
FEMS Microbiol Lett ; 366(14)2019 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-31390020

RESUMEN

Actinobacteria are known by their ability to produce several antimicrobial compounds of biotechnological interest. Thus, in this study, we isolated and identified by partial 16S RNA sequencing ∼100 actinobacteria isolates from guarana (Paullinia cupana) bulk soil. Besides, we isolated from the actinobacteria Streptomyces morookaense AM25 a novel cyclic peptide, named gloeosporiocide, molecular formula C44H48N11O7S3 (calculated 938.2901), and characterized by the presence of cyclized cysteins to form three thiazols. The novel compound had activity against the plant pathogen Colletotrichum gloeosporioides, assayed by the paper disk diffusion method (42.7% inhibition, 0.1 mg disk-1) and by the microdilution assay (1.25 g L-1). Our results reveal the potential of the actinobacteria from the Amazon rhizospheric soils as biocontrol agents as well as producers of new compounds with antifungal activity. Thus, this work constitutes a step forward in the development of the biotechnology of actinobacteria in the production of compounds of agronomic interest.


Asunto(s)
Antibiosis , Antifúngicos/aislamiento & purificación , Antifúngicos/farmacología , Péptidos Cíclicos/aislamiento & purificación , Péptidos Cíclicos/farmacología , Microbiología del Suelo , Streptomyces/metabolismo , Antifúngicos/química , Cromatografía Líquida de Alta Presión , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Péptidos Cíclicos/química , Filogenia , ARN Ribosómico 16S/genética , Espectrometría de Masas en Tándem
5.
Acta sci., Biol. sci ; Acta sci., Biol. sci;41: e48785, 20190000. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1460898

RESUMEN

Fungi are present in the most diverse environments including the interior of plant tissues, living as endophytes without causing apparent damage. These endophytes are producers of secondary metabolites, also known as natural products, such as fungicides. Here, we evaluated the ethyl acetate fractions obtained from endophytic fungiisolated from plants in the genus Begonia. The fractions were submitted to inhibitorytest against the plant pathogens Diaporthe phaseolorum and Colletotrichum gloeosporioides. From the 88 ethyl acetate fractions evaluated, 14.7 % inhibited C. gloeosporioidesand 11.3 %inhibited D. phaseolorum. One fungal isolate displaying an active fraction was selected for chemical investigation. The fungus identified as Neopestalotiopsissp., produced a compound that was active against D. phaseolorum, with a MIC of 312 μg mL-1(1,695.3 μM). The compound was identified by mass spectrometry and 1H NMR as the known compound fumiquinone B. The results highlight that the endophytes are capable of producing compounds that may be used to control plant pathogens. The compound fumiquinone B is reported for the first time as an antifungal agent against D. phaseolorum, a relevant plant pathogen worldwide. This is also the first report of the production of fumiquinone B by the genus Neopestalotiopsis.


Asunto(s)
Antifúngicos/metabolismo , Hongos/inmunología
6.
Ciênc. agrotec., (Impr.) ; 41(2): 201-208, Mar.-Apr. 2017. tab, graf
Artículo en Inglés | LILACS | ID: biblio-890610

RESUMEN

ABSTRACT One of the main problems facing agriculture is the loss of production as a result of the attack of agricultural pests. Alternative ways to work around this problem are being sought. There are substances called acylsugars that are naturally produced by the wild tomato species S. pennellii and affect arthropod pests. The objectives of this work were to synthesize two acylsugars and assess the biological effect of these on the arthropod pests Bemissia tabaci and Tetranycus urticae. The syntheses were performed via the reactions of glucose and sucrose (saccharose) with acetic anhydride using sodium acetate as the catalyst. The products of these reactions were sucrose octa-acetate and glucose penta-acetate, the structures of which were confirmed by spectroscopic techniques. In a resistance test against the mite, a linear correlation between the concentration of the synthesized substances, and the dislocation of the mite was obtained. A delay in the hatching of the arthropod eggs was observed, causing a mortality rate of approximately 95% in the 1st instar larvae of mites that was confirmed in adults. In the biological tests with Bemisia tabaci, there was a low rate of hatching and emergence, and the effect on the nymphs was the deformation of the emergent adults.


RESUMO Um dos grandes problemas que a agricultura enfrenta é a perda de produção causada pelo ataque de pragas agrícolas. Assim, buscam-se maneiras alternativas de contornar esse problema. Dentre esses, encontram-se substâncias, denominadas de acilaçúcars, que são produzidas naturalmente por espécies selvagens do tomate S. pennellii e que apresentam efeito sobre artrópodes-praga. Os objetivos desse trabalho foram sintetizar dois compostos de acilaçúcares e avaliar o efeito biológico destas sobre os artrópodes-praga Bemissia tabaci e Tetranycus urticae. A síntese foi feita via as reações de glicose e sacarose com anidrido acético, utilizando acetato de sódio como catalisador. Os produtos dessas reações foram o octa-acetato de sacarose e o penta-acetato de glicose, cujas estruturas foram confirmadas por técnicas espectroscópicas. No teste de resistência do ácaro, foi possível obter um ajuste linear entre a concentração das substâncias sintetizadas e o deslocamento do ácaro. Ambas as substâncias obtidas apresentaram um atraso na eclosão dos ovos do artrópode, ocasionando uma mortalidade de aproximadamente 95% em ácaros de 1º ínstar que foram confirmadas em adultos. Nos testes biológicos com Bemisia tabaci, verificou-se uma baixa taxa de eclosão e emergência, sendo que o efeito sobre as ninfas foi a má formação para adultos emergidos.

7.
Artículo en Inglés | MEDLINE | ID: mdl-27525023

RESUMEN

The chemical composition and biological activity of a sample of yellow propolis from Mato Grosso do Sul, Brazil (EEP-Y MS), were investigated for the first time and compared with green, brown, and red types of Brazilian propolis and with a sample of yellow propolis from Cuba. Overall, EEP-Y MS had different qualitative chemical profiles, as well as different cytotoxic and antimicrobial activities when compared to the other types of propolis assessed in this study and it is a different chemotype of Brazilian propolis. Absence of phenolic compounds and the presence of mixtures of aliphatic compounds in yellow propolis were determined by analysing (1)H-NMR spectra and fifteen terpenes were identified by GC-MS. EEP-Y MS showed cytotoxic activity against human tumour strain OVCAR-8 but was not active against Gram-negative or Gram-positive bacteria. Our results confirm the difficulty of establishing a uniform quality standard for propolis from diverse geographical origins. The most appropriate pharmacological applications of yellow types of propolis must be further investigated.

8.
Ciênc. rural ; Ciênc. rural (Online);46(5): 927-932, May 2016. tab
Artículo en Inglés | LILACS | ID: lil-777285

RESUMEN

ABSTRACT: The purpose of this study was to determine the physicochemical characteristics of pollen collected by the Amazonian stingless bees Melipona seminigra and Melipona interrupta, in order to verify whether their characteristics meet the physicochemical requirements established by the Brazilian Technical Regulation for Identity and Quality of Bee Pollen. Physicochemical analyses were performed through official analytical methods. Results of pollen analyses collected by M. seminigra and M. interrupta were respectively as follows: moisture: 53.39 and 37.12%; protein: 37.63 and 24.00%; lipids: 10.81 and 6.47%; ash: 4.03 and 2.74%; crude fiber: 9.30 and 13.65%; carbohydrates: 25.66 and 44.27%; energy: 350.47 and 331.33kcal%; pH: 3.70 and 3.34; total solids: 46.60 and 62.87%, and water activity: 0.91 and 0.85. The percentages of moisture and pH in pollen collected by both studied bees are not in agreement with the Technical Regulation for bee pollen. Since some characteristics, which are inherent to the Melipona pollen, were not in conform to the current Regulation, we recommend that further studies should be conducted to better characterize it, and correct the Regulation, if necessary.


RESUMO: O objetivo deste estudo foi determinar as características físico-químicas do pólen coletado pelas abelhas amazônicas sem ferrão, Melipona seminigra e Melipona interrupta, para verificar se suas características atendem aos requisitos físico-químicos estabelecidos no Regulamento Técnico Brasileiro de Identidade e Qualidade de Pólen Apícola. As análises físico-químicas foram realizadas através de métodos analíticos oficiais. Os resultados das análises do pólen coletado por M. seminigra e M. interrupta foram, respectivamente: umidade: 53,39 e 37,12%; proteínas: 37,63 e 24,00%; lipídeos: 10,81 e 6,47%; cinzas: 4,03 e 2,74%; fibra bruta: 9,30 e 13,65%; carboidratos: 25,66 e 44,27%; energia: 350,47 e 331,33kcal%; pH: 3,70 e 3,34; sólidos totais: 46,60 e 62,87%; e atividade de água: 0,91 e 0,85. O percentual de umidade e o pH do pólen coletado por ambas as abelhas estudadas está em desacordo com o Regulamento Técnico para pólen apícola. Recomendamos que sejam realizados mais estudos para melhor caracterizar este produto e atualizar o Regulamento vigente, se necessário, pois algumas características que não atendem ao Regulamento são inerentes ao pólen de Melipona.

9.
Physiother Theory Pract ; 31(5): 354-61, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25585514

RESUMEN

Recently, low-level laser (light) therapy (LLLT) has been used to improve muscle performance. This study aimed to evaluate the effectiveness of near-infrared light-emitting diode therapy (LEDT) and its mechanisms of action to improve muscle performance in an elite athlete. The kinetics of oxygen uptake (VO2), blood and urine markers of muscle damage (creatine kinase--CK and alanine), and fatigue (lactate) were analyzed. Additionally, some metabolic parameters were assessed in urine using proton nuclear magnetic resonance spectroscopy ((1)H NMR). A LED cluster with 50 LEDs (λ = 850 nm; 50 mW 15 s; 37.5 J) was applied on legs, arms and trunk muscles of a single runner athlete 5 min before a high-intense constant workload running exercise on treadmill. The athlete received either Placebo-1-LEDT; Placebo-2-LEDT; or Effective-LEDT in a randomized double-blind placebo-controlled trial with washout period of 7 d between each test. LEDT improved the speed of the muscular VO2 adaptation (∼-9 s), decreased O2 deficit (∼-10 L), increased the VO2 from the slow component phase (∼+348 ml min(-1)), and increased the time limit of exercise (∼+589 s). LEDT decreased blood and urine markers of muscle damage and fatigue (CK, alanine and lactate levels). The results suggest that a muscular pre-conditioning regimen using LEDT before intense exercises could modulate metabolic and renal function to achieve better performance.


Asunto(s)
Luz , Terapia por Luz de Baja Intensidad , Contracción Muscular/efectos de la radiación , Músculo Esquelético/efectos de la radiación , Resistencia Física/efectos de la radiación , Carrera , Adulto , Alanina/orina , Biomarcadores/sangre , Biomarcadores/orina , Creatina Quinasa/sangre , Método Doble Ciego , Humanos , Cinética , Ácido Láctico/sangre , Masculino , Fatiga Muscular/efectos de la radiación , Músculo Esquelético/metabolismo , Consumo de Oxígeno/efectos de la radiación , Espectroscopía de Protones por Resonancia Magnética , Factores de Tiempo
10.
Braz. arch. biol. technol ; Braz. arch. biol. technol;54(1): 61-66, Jan.-Feb. 2011. ilus, graf, tab
Artículo en Inglés | LILACS | ID: lil-576759

RESUMEN

The dichloromethane extract of Almeidea coerulea stems yielded the (11-hydroxyrutaecarpine alkaloid reported for the first time from this species) and the triterpene (28-hydroxy-28, 29-dihydrolupeol). The dictamine, skimianine, sitosterol and stigmasterol were also isolated from methanol extract. Extracellular forms of Leishmania amazonensis (promastigotes) was tested with dichloromethane extract and 28-hydroxy-28, 29-dihydrolupeol with showed anti-leishmanial activity above 0.1 mg/mL and 75µg/mL (inhibited 50 percent promastigote growth), respectively.

11.
Acta amaz ; Acta amaz;41(2): 285-288, 2011. ilus, tab
Artículo en Portugués | LILACS, VETINDEX | ID: lil-586485

RESUMEN

Estudos fitoquímicos prévios com resíduos do cerne de pau-rainha (Brosimum rubescens), identificaram um alto teor de xantiletina, uma cumarina com potencial biológico. Dando prosseguimento aos estudos com serragens desta espécie, este estudo relata a densidade básica bem como o isolamento e identificação do triterpeno 3ß-acetoxi-olean-12-eno-28-al e do ß- sitosterol nos extratos hexânico e metanólico do alburno da planta. A estrutura do triterpeno foi determinada com base nos espectros de RMN em 1D (¹H e 13C) e 2D (HSQC e HMBC) além de comparação com dados da literatura. A densidade básica encontrada para o alburno foi de 0,58 g cm-3 que, embora seja inferior a do cerne, poderá ser utilizada na confecção de vários produtos, inclusive em técnicas de marchetaria.


Previous phytochemical studies on residues of pau-rainha's heartwood (Brosimum rubescens) showed a high content of xanthyletin, a coumarin with biological potential. Continuing our studies with sawdust of this species, this work relates the basic density, isolation and identification of the triterpene 3ß-acetoxy-olean-12-ene-28-al and ß-sitosterol in n-hexane and MeOH extracts of the plant´s sapwood. The structure of the triterpene was determined on the basis of NMR spectra in 1D (¹H and 13C) and 2D (HSQC and HMBC) and comparison with literature data. The basic density found for sapwood was 0.58 g cm-3, that even so is inferior the one of heartwood, could be used in the confection of some products, also in marquetry techniques.


Asunto(s)
Triterpenos , Residuos , Madera , Moraceae
12.
RBCF, Rev. bras. ciênc. farm. (Impr.) ; RBCF, Rev. bras. ciênc. farm. (Impr.);44(4): 749-754, out.-dez. 2008. ilus, tab
Artículo en Portugués | LILACS | ID: lil-507925

RESUMEN

A esquistossomose, uma importante doença no Brasil, é causada por trematódeo pertencente ao gênero Schistosoma, atingindo milhões de pessoas, numa das maiores regiões endêmicas dessa doença em todo globo. O principal objetivo desse trabalho foi sintetizar o derivado 6-formil-oxamniquina e avaliar sua atividade biológica. O derivado 6-formil- oxamniquina foi obtido por oxidação da oxamniquina com dióxido de manganês empregando diclorometano como solvente, à temperatura ambiente, por 24 horas. Sua obtenção foi confirmada por espectrometria na região de infravermelho e espectroscopia de RMN 13C e ÕH, apresentando atividade similar quando comparada à oxamniquina comercial (Mansil®).


Schistosomiasis, an important disease in Brazil, is caused by a trematode of the genus Schistosoma, reaching millions of person in one of the most endemic region of this disease in the whole globe. The main goal of this work was to syntetize the 6-formyl-oxamniquine derivative and evaluate its biological activity. The 6-formyl-oxamniquine derivative was obtained by the oxidation of oxamniquine with MnO2, applying CH2Cl2 as solvent at room temperature for 24 hours. The obtaintion of 6-formyl-oxamniquine derivative compound was confirmed by IR spectroscopy and 13C NMR and ÕH NMR, presenting similar activity when compared to the commercial oxamniquine (Mansil®).


Asunto(s)
Animales , Masculino , Femenino , Ratones , Evaluación de Medicamentos , Oxamniquina/farmacología , Esquistosomiasis , Análisis Espectral/métodos , Esquistosomiasis mansoni
13.
Acta amaz ; Acta amaz;38(4): 749-752, dez. 2008. ilus, tab
Artículo en Portugués | LILACS | ID: lil-504709

RESUMEN

A indústria da madeira do estado de Amazonas (Brasil) contribui com a produção de uma quantidade grande de resíduos. Este trabalho visa indicar o uso final para espécie florestal pau-rainha (Brosimum rubescens Taubert, Moraceae). Os resíduos descartados durante o processamento mecânico da madeira foram utilizados na confecção de artefatos como: instrumentos musicais e artigos decorativos gerando resíduos menores (serragens). Foram obtidos extratos das serragens do cerne e alburno por maceração com hexano e metanol. O teor extrativo no cerne foi 19,87 por cento e a porcentagem (com relação a serragem) de xantiletina (2,2-dimetilcromeno cumarina) obtida foi 2,35 por cento. Não foi detectada a cumarina nos extratos do alburno. A xantiletina é reportada pelas atividades antiplaquetária, antifúngica e herbicida e alguns derivados possuem atividade em linhagens de células leucêmicas. A proposta de uso final adequado dos resíduos de pau-rainha para confecção de artefatos tem uma grande importância social e a busca de metabólitos secundários é bastante promissora pois estes podem ser transformados em novos produtos.


Timber industry of Amazonas state (Brazil) contribute with the production of great amount of residues. This paper aims to indicating end-uses for this forest species pau-rainha (Brosimum rubescens Taubert, Moraceae). The residues discharged during the mechanical processing in timber production were used as manufactured goods such as: musical instruments and decorative articles generating less wastes in sawmills. They were carried sawdust of the heartwood and sapwood and extraction by maceration with hexane and methanol. The heartwood extractive yield was 19.87 percent and content of xanthyletin (2,2-dimethylchromene coumarin) was 2.35 percent with basis dry mass. It was not detected the coumarin in extracts of sapwood. Xanthyletin is reported as antiplatelet, antifungal and herbicide and some its derivatives have a leukaemic cells lineage activities. The proposal of adequate end-uses of "pau-rainha" as manufacture-goods is a great social benefit and the search of secondary metabolites is quite promising it can be transformed into novel products.


Asunto(s)
Clima Tropical , Residuos , Madera
14.
Rev. Inst. Med. Trop. Säo Paulo ; Rev. Inst. Med. Trop. Säo Paulo;50(1): 26-28, Jan.-Feb. 2008. ilus, tab
Artículo en Inglés | LILACS | ID: lil-476759

RESUMEN

The objective of this study was to evaluate the larvicidal activity of diterpenoids obtained from the oil-resin of Copaifera reticulata against Aedes aegypti larvae, the principal vector of dengue and urban yellow fever. Four diterpenes were obtained from oil-resin extraction with organic solvents and subsequent chromatographic and spectroscopic procedures allowed to isolation and identification of these compounds as 3-b-acetoxylabdan-8(17)-13-dien-15-oic acid (1), alepterolic acid (2), 3-b-hidroxylabdan-8(17)-en-15-oic acid (3), and ent-agatic acid (4). Each compound was previously dissolved in dimethylsulphoxide, and distilled water was added to obtain the desired concentrations. Twenty larvae of third instars were placed into plastic beckers, containing the solution test (25 mL), in a five repetitions scheme, and their mortality, indicated by torpor and darkening of the cephalic capsule, was recorded after 48h. Probit analyses were used to determine lethal concentrations (LC50 and LC90) and their respective 95 percent confidence intervals. This study showed that only diterpenoids 1 and 2 exhibited larvicidal properties with LC50 of 0.8 ppm and 87.3 ppm, respectively, revealing the former as the most toxic compound against third instars of Ae. aegypti. Therefore, this compound seems to be an interesting source for new metabolite to be exploited.


O objetivo deste trabalho foi avaliar a atividade larvicida de diterpenos isolados do óleo-resina de Copaifera reticulata sobre Aedes aegypti, principal vetor de dengue e febre amarela urbana. Quatro diterpenóides foram obtidos a partir da extração do óleo-resina com solventes orgânicos e, subseqüentes procedimentos cromatográficos e espectroscópicos permitiram o isolamento e a identificação desses compostos como ácido 3-b-acetoxylabdan-8(17)-13-dien-15-óico (1), ácido alepterólico (2), ácido 3-b-hidroxylabdan-8(17)-en-15-óico (3) e ácido ent-agático (4). Cada um desses compostos foi previamente solubilizado em dimetilsulfóxido, acrescentando-se água, até se obterem as concentrações desejadas. Em cada bioensaio foram utilizadas 20 larvas de 3° estádio de Ae. aegypti colocadas em 25 mL da solução-teste. Foram feitas cinco repetições, e a mortalidade avaliada 48 h após a exposição, indicada pela ausência de movimentos e escurecimento da cápsula cefálica. Os dados obtidos da mortalidade x concentração (ppm) foram analisados, em gráfico de Probit para avaliar as concentrações letais (CL50 e CL90). Este estudo revelou que os diterpenóides 1 e 2 mostraram atividade larvicida com CL50 de 0,8 e 87,3 ppm, respectivamente, sendo o diterpeno 1 o composto mais promissor a ser usado como larvicida para o controle de Ae. aegypti.


Asunto(s)
Animales , Aedes , Bálsamos/química , Diterpenos/aislamiento & purificación , Insecticidas , Diterpenos/química , Larva/efectos de los fármacos
15.
Microvasc Res ; 75(1): 34-44, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17585952

RESUMEN

A polysaccharide (Sarg) extracted from the brown marine alga Sargassum stenophyllum was studied for its antivasculogenic effects in both in vivo and in vitro assays, as well as for its capacity to modify embryonic morphogenetic processes endogenously regulated by bFGF, a well-known angiogenic stimulator. The antivasculogenic activity of Sarg (6-1500 microg/implant) was evaluated in a chick yolk sac membrane assay and the embryonic morphogenesis was measured as the percentage cephalic length. Sarg alone (96-1500 microg/implant) and co-administered with hydrocortisone (HC; 156 microg/implant) decreased the vitelline vessel number by 23-100% and 54-100% respectively. The polysaccharide potentiated the antivasculogenic effect of HC (42% inhibition). Basic fibroblast growth factor-stimulated vasculogenesis (141% of vessels as compared to control) was partially reversed by Sarg. The treatment with Sarg also decreased the percentage cephalic length of 3.5- and 4-day chick embryos (as cultured in vivo and in vitro, respectively), uncoupled from any impairment in the body shape or embryotoxic effect. Due to polyanionic characteristics of Sarg, which are similar to those seen in the heparin molecule, we suggest that this polysaccharide should modulate the activity of heparin-binding vascular growth factors (such as bFGF, which also acts as a morphogen) mimetically interfering with heparan sulfate proteoglycans during microvessel formation.


Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Membrana Corioalantoides/irrigación sanguínea , Neovascularización Fisiológica/efectos de los fármacos , Polisacáridos/farmacología , Sargassum , Inhibidores de la Angiogénesis/química , Inhibidores de la Angiogénesis/aislamiento & purificación , Animales , Vasos Sanguíneos/efectos de los fármacos , Vasos Sanguíneos/embriología , Vasos Sanguíneos/metabolismo , Embrión de Pollo , Relación Dosis-Respuesta a Droga , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Hidrocortisona/farmacología , Estructura Molecular , Morfogénesis/efectos de los fármacos , Polisacáridos/química , Polisacáridos/aislamiento & purificación , Sargassum/química , Factores de Tiempo
16.
Acta amaz ; Acta amaz;37(3): 447-450, 2007. ilus, tab
Artículo en Portugués | LILACS | ID: lil-474444

RESUMEN

O extrato obtido em metanol da polpa de frutos Endopleura uchi foi submetido a fracionamento utilizando-se técnicas cromatográficas convencionais levando ao isolamento de bergenina. Na análise da composição dos carotenóides foi evidenciada a predominância de beta-caroteno (16,57 mig.g-1). Os isômeros do beta-caroteno foram detectados, trans-beta-caroteno (89,3 por cento), 13-cis-beta-caroteno (8 por cento) e 9-cis-beta-caroteno (3 por cento). Considerando a importância do papel nutricional dos carotenóides e a bioatividade do glicosídeo bergenina, esse estudo sugeriu o potencial desse fruto como alimento funcional.


The extract obtained in methanol from the fruits pulp of Endopleura uchi was fractionated using conventional chromatographic tecniques to isolate bergenin. In the analysis of the composition of carotenoids was evidenced the predominance of beta-carotene (16.57 mug.g-1). The isomers of beta-carotene: trans-beta-carotene (89.3 percent), 13-cis-beta-carotene (8 percent) and 9-cis-beta-carotene (3 percent) were detected. Considering the importance of the nutritional role of carotenoids and the bioactivity of the bergenina, this study suggested the potential of this fruit as functional food.


Asunto(s)
beta Caroteno , Frutas
17.
Rev. bras. farmacogn ; 16(2): 164-169, abr.-jun. 2006. ilus, tab
Artículo en Portugués | LILACS | ID: lil-570974

RESUMEN

Do extrato diclorometano do caule de Almeidea coerulea (Nees & Mart.) A. St.-Hil. foi isolado um triterpeno o 20-hidroxi-diidrolupeol (1), e do extrato metanólico foram isolados os alcalóides dictamina (2) e eskimianina (3), além de uma mistura dos esteróides sitosterol (4) e estigmasterol (5). A identificção substâncias foi realizada pela análise dos espectros de Massas, RMN ¹H, RMN 13C, HSQC, HMBC, e por comparação com dados da literatura.


From the dichloromethane extract of Almeidea coerulea stem one triterpene, 20-hydroxy-dihydrolupeol was isolated (1) and from the methanol extract the known alkaloids dictamnine (2) and skimmianine (3), as well the steroids sitosterol (4) and stigmasterol (5). The identification of these compounds was performed on the basis of spectroscopic analyses (MS, ¹H NMR, 13C NMR, HSQC and HMBC) as well as comparison with literature data.

18.
RBCF, Rev. bras. ciênc. farm. (Impr.) ; RBCF, Rev. bras. ciênc. farm. (Impr.);40(1): 43-51, jan.-mar. 2004. ilus, tab, graf
Artículo en Inglés | LILACS | ID: lil-391011

RESUMEN

Inclusion complexes of rifampicin (RP) were prepared with hydroxypropyl-ß-cyclodextrin (HPßCD). The aqueous solubility of RP increased linearly with cyclodextrin concentration in all range of the solubility diagram. The data was analyzed using the framework of Higuchi and Connors. The stability constant (K) values for RP/HPßCD complex at pH 6.9 were 18 and 120-125 M-1 for ionic strength 0.01 and 0.18M, respectively. The analysis of the chemical shift data of 1H and 15N for free RP and RP/HPßCD inclusion complex reveal that only peaks of the side chain related to the piperazine ring of RP change substantially, probably due to interaction of this region of RP molecule with the hydrophobic core of HPßCD...


Asunto(s)
Ciclodextrinas , Modelos Moleculares , Rifampin , Espectroscopía de Resonancia Magnética/métodos , Solubilidad
19.
Mem. Inst. Oswaldo Cruz ; 98(4): 549-552, June 2003. ilus, tab, graf
Artículo en Inglés | LILACS | ID: lil-344253

RESUMEN

The bioassay-guided fractionation of stems from Kielmeyera variabilis, traditionally used in Brazilian folk medicine, yielded assiguxanthone-B (1), kielcorin (4), 2,5-dihydroxybenzoic acid (3), and a mixture of xanthones containing assiguxanthone-B (1) and 1,3,5,6-tetrahydroxy-2-prenylxanthone (2) (1:1 w/w). The xanthone mixture inhibited Staphylococcus aureus and Bacillus subtilis at a concentration of 6.25 µg/ml. When tested alone, the minimal inhibitory concentration of assiguxanthone-B was 25 µg/ml against B. subtilis. Kielcorin and 2,5-dihydroxybenzoic acid were inactive against both strains. None of the fractions was active against Escherichia coli or Pseudomonas aeruginosa. Viable cells of S. aureus were reduced by a 1-3 log CFU/ml within 12 h after exposure of one to eight times the MIC of the xanthone mixture. It is not known whether the tetrahydroxy-2-prenylxanthone or other components of the xanthone mixture are responsible for the main antibacterial activity or whether additive or synergistic action is involved


Asunto(s)
Antiinfecciosos , Bacterias Gramnegativas , Bacterias Grampositivas , Ericales , Xantenos , Antiinfecciosos , Bacillus subtilis , Sinergismo Farmacológico , Escherichia coli , Pruebas de Sensibilidad Microbiana , Extractos Vegetales , Pseudomonas aeruginosa , Staphylococcus aureus , Factores de Tiempo , Xantenos
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