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1.
Rev. bras. farmacogn ; 26(3): 375-378, May-June 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-784284

RESUMO

Abstract Solanum paniculatum L., Solanaceae, locally known as "jurubeba", is widely used in Brazil for culinary purposes, and in folk medicine to treat of diverse disorder including gastric dysfunctions. In this study we investigated the antidiarrheal activity of S. paniculatum roots extract in rats at different concentrations (125, 250 and 500 mg/kg, p.o) using different experimental models such as castor oil-induced diarrhea, enteropooling and gastrointestinal motility, determined by in vivo experimental models. The major compound of root extract was characterized as chlorogenic acid based in the IR, 1D and 2D NMR analysis. All the extract doses achieved antidiarrheal potency, as indicated by reduced weight of feces in castor oil-induced diarrhea, decreased intestinal motility and significantly inhibited castor oil-induced enteropooling compared to the vehicle group. The highest dose (500 mg/kg) produced greater anti-motility effect and better reduction of enteropooling, similar to the reference drug Loperamide (5 mg/kg). Extract from S. paniculatum L. roots had antidiarrheal activity, as shown by the lower weight of the feces as well as decrease in the accumulation of intestinal fluid and slower transit, justifying the traditional use of plant for diarrhea.

2.
Toxicol Rep ; 3: 516-522, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28959575

RESUMO

Considering the increase in consumption of Cannabis sativa and the use of the compound ß-carotene (BC) as supplement, we investigated potential changes in the chemical and biological proprieties of BC after exposure to C. sativa smoke (CSS). Our results showed that the BC exposed to CSS underwent 98.8% degradation and suffered loss of its antiradical activity. The major degradation products identified were 3-hydroxy-2,4,4-trimethylpentyl)2-methylpropanoate and (2-ethyl-3-hydroxyhexyl)2-methylpropanoate compounds. These are found in higher levels in the exhalations of colorectal cancer patients and are similar to the toxic products associated with lipid peroxidation of polyunsaturated fatty acids. In toxicological assays using micro-crustacean Artemia salina the BC was non-toxic, while the BC degraded by CSS had a toxicity of LC50 = 397.35 µg/mL. In Wistar rats, females treated with BC degraded by CSS (BCCSS) showed whitish liver spots, alterations in liver weight and in bilirubin and alkaline phosphatase levels, and decrease in the number of leukocytes associated with atypical lymphocytosis. In male rats, there was an increase in the number of leukocytes when compared to the control group. In the histopathological analysis, the cortical region of the kidneys showed the presence of discrete amorphous eosinophilic material (cylinders) in the lumen of the proximate and distal convoluted tubules. In general, the BC in contact with CSS undergoes chemical changes and exhibits toxicity to rats and Artemia salina.

3.
Nat Prod Commun ; 10(11): 1809-10, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26749802

RESUMO

This present work addresses research on the discovery of new compounds from natural sources. It is based on a study of Mangifera indica leaf metabolism by the Tropidacris collaris grasshopper. We found that the grasshopper hydrolyzed the flavonoid isoquercitrin to quercetin when the O-glycosidic bond was broken and sugar released as a probable energy source for the insect. There was not, however, hydrolysis of the major compound in the leaves, mangiferin, which contains the C-glycosidic bond. All compounds were isolated and their chemical structure determined by UV, IR, MS, 1H and 13C NMR.


Assuntos
Gafanhotos/metabolismo , Mangifera/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Animais , Hidrólise , Mangifera/química
4.
Bol. latinoam. Caribe plantas med. aromát ; 13(3): 270-277, mayo 2014. tab, ilus
Artigo em Inglês | LILACS | ID: lil-768853

RESUMO

The composition of the essential oil from the leaves of Piper marginatum (Piperaceae) shows circadian variation and a higher yield during high solar incidence. The essential oils samples were investigated by GC-FID and GC-MS, which allowed identification of 29 compounds. Principal component analysis (PCA) and cluster analysis (CA) showed a significant quantitative variability in the chemical composition of the studied samples as well as a correlation between the oil profiles and the collection time. Two main groups were observed, with predominance of phenylpropanoids or sesquiterpenes. The predominant chemical compounds were phenylpropanoids, having as main representative (Z)-asarone and (E)-asarone.


La composición del aceite esencial de hojas de Piper marginatum (Piperaceae) muestra una variación circadiana y un mayor rendimiento durante la mayor incidencia solar. Las muestras de aceites esenciales se investigaron por GC-FID y GC-MS, lo que permitió la identificación de 29 compuestos. El análisis de componentes principales y el análisis de conglomerados mostraron una variación cuantitativa significativa en la composición química de las muestras estudiadas, así como una correlación entre los perfiles del aceite esencial y el tiempo de recolección. Se observaron dos grupos principales, con predominio de fenilpropanoides o sesquiterpenos. Los compuestos predominantes fueron los fenilpropanoides, (Z)-asarona y (E)-asarona.


Assuntos
Óleos Voláteis/química , Ritmo Circadiano , Folhas de Planta/química , Piperaceae/química , Anisóis , Análise por Conglomerados , Cromatografia Gasosa/métodos , Análise de Componente Principal , Sesquiterpenos
5.
Chirality ; 25(4): 211-4, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23532996

RESUMO

A simple, rapid, and sensitive method for the analysis of paroxetine, in tablets as well as the pure drug, by circular dichroism is described. The method was validated for repeatability, linearity, limit of detection, limit of quantification, and recovery according to the International Conference on Harmonization guidelines. Excellent results were obtained, within the globally accepted validation reference values, particularly taking into account the low concentration levels investigated. This is the first report of the quantitation of paroxetine, a chiral drug, without previous separation of the analyte. Additionally, the solid state CD spectrum of PXT was obtained.


Assuntos
Dicroísmo Circular/métodos , Paroxetina/análise , Química Farmacêutica , Limite de Detecção , Paroxetina/química , Estereoisomerismo
6.
J Insect Physiol ; 58(12): 1663-8, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23108151

RESUMO

The chemical volatiles from plant leaves and their biological activities have been extensively studied. However, no studies have addressed plant-chemical volatiles after undergoing the digestive process in host insects. Here we describe for the first time chemical profiles of volatile constituents from Solanum paniculatum and Mangifera indica leaves metabolized by grasshoppers. Both profiles were qualitatively and quantitatively different from the profiles of non-metabolized leaves. The amount of nerolidol, the major constituent of S. paniculatum leaves, decreased and other sesquiterpenes, such as spathulenol, were formed during the digestive process of the grasshopper Chromacris speciosa. In M. indica, the presence of phenylpropanoids was observed (dillapiole, Z-asarone, E-asarone and γ-asarone) in the leaves metabolized by the grasshopper Tropidacris collaris, but these compounds were not found in the non-metabolized leaves.


Assuntos
Gafanhotos/metabolismo , Herbivoria , Mangifera/química , Solanum/química , Compostos Orgânicos Voláteis/metabolismo , Animais , Folhas de Planta/química , Sesquiterpenos/metabolismo
7.
Nat Prod Commun ; 7(8): 1103-6, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22978240

RESUMO

Electrophysiological responses based on electroantennographic detection (GC-EAD) and electroantennography (EAG) analysis of Naupactus bipes beetles (Germar, 1824) (Coleoptera: Curculionidae: Brachycerinae) were used to test volatile oils of Piper gaudichaudianum, P. regnellii and P. hispidum. In the EAG experiments, female and male beetles showed significant EAG response to the three volatile oils of Piper species, with the females' responses slightly higher than the males'. The experiments with GC-EAD revealed that some terpenoids (namely, alpha-pinene, beta-pinene, myrcene, alpha-copaene and germacrene) present in the leaf essential oils of the Piper species are perceptible to female and male beetles.


Assuntos
Besouros/efeitos dos fármacos , Óleos Voláteis/farmacologia , Piperaceae/química , Óleos de Plantas/farmacologia , Terpenos/farmacologia , Animais , Fenômenos Eletrofisiológicos/efeitos dos fármacos , Feminino , Masculino , Óleos Voláteis/química , Óleos de Plantas/química , Terpenos/química
8.
Phytochem Anal ; 23(6): 604-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22407565

RESUMO

INTRODUCTION: The phytochemistry of species of the genus Piper has been studied extensively, including Piper solmsianum. However, no studies have addressed the phytochemistry of the sap content of Piper species. OBJECTIVE: To evaluate the transferring of secondary compounds from the saps of P. solmsianum to the honeydew of Edessa meditabunda. METHODOLOGY: The honeydew of E. meditabunda and saps of P. solmsianum were analysed by GC-MS, (1) H-NMR and LC-MS. RESULTS: The lignan (-)-grandisin and the phenylpropanoid (E)-isoelemicin were detected in both saps of P. solmsianum and honeydew of E. meditabunda. CONCLUSION: Analysis of honeydew secreted by the sap-sucking insect E. meditabunda indicated that (-)-grandisin and (E)-isoelemicin are absorbed from the phloem of Piper solmsianum.


Assuntos
Furanos/análise , Heterópteros/química , Lignanas/análise , Piper/química , Piper/metabolismo , Pirogalol/análogos & derivados , Animais , Furanos/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Heterópteros/metabolismo , Lignanas/metabolismo , Floema/química , Floema/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Pirogalol/análise , Pirogalol/metabolismo , Xilema/química , Xilema/metabolismo
9.
Phytochemistry ; 69(11): 2157-61, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18565552

RESUMO

The biotransformation of the major Piper solmsianum leaf phenylpropanoids, such as the tetrahydrofuran lignan grandisin and derivatives was investigated in the beetle Naupactus bipes as well as in the caterpillars Heraclides hectorides and Quadrus u-lucida. Analysis of fecal material indicated that metabolism occurred mainly through mono- and di-O-demethylation at para positions of 3,4,5-trimethoxyphenyl rings of tetrahydrofuran lignans during digestion by these insects. Additionally, 3-hydroxy-4,5-dimethoxycinnamyl and 3,4,5-trimethoxycinnamyl alcohols were identified in fecal extracts of N. bipes.


Assuntos
Besouros/metabolismo , Furanos/química , Furanos/metabolismo , Lepidópteros/metabolismo , Lignanas/química , Lignanas/metabolismo , Piper/metabolismo , Animais , Estrutura Molecular , Propanóis/química , Propanóis/metabolismo
10.
Rev. bras. entomol ; 52(1): 72-77, 2008. ilus, tab
Artigo em Inglês | LILACS | ID: lil-481215

RESUMO

Piperaceae species have been placed among the basal angiosperm and are adapted to a variety of habitats including moist forests, secondary vegetation and dry high lands. The major anatomical/morphology features are of small trees, vines, and shrubs for Piper species, while the epiphytic and succulent characteristics are predominant forms among Peperomia species. Their secondary chemistry can be mostly represented by amides, phenylpropanoids/lignoids, and chromenes in addition to a phletoria of biosynthetically mixed-origin secondary compounds. Although several amides and lignans are known as insecticides, several phytophagous insects, among which some considered pests of economic importance, have been observed feeding vigorously on Piperaceae species. Herein we describe the feeding preferences of fourteen phytophagous species of Coleoptera, Lepidoptera and Hemiptera over approximately fifty Piperaceae species observed in São Paulo, SP, Brazil, in a long-term basis.


As espécies de Piperaceae têm sido posicionadas entre as angiospermas basais e são frequentemente encontradas em habitats diversificados que incluem matas ciliares, vegetação secundária e campos rupestres. As espécies de Piper possuem hábitos de plantas herbáceas, arboretos e trepadeiras enquanto que, no caso de Peperomia, é freqüente o hábito de epífitas e suculentas. As classes de metabólitos secundários que caracterizam espécies de Piperaceae são amidas, fenilpropanóides/lignóides e cromenos, além de diversos outros de origem biossintética mista de menor representatividade. Apesar de muitos desses possuírem atividades inseticidas, diversos insetos fitófagos, alguns considerados pragas de importância econômica, foram observados alimentando-se de espécies de Piperaceae. Neste trabalho são relatadas as preferências alimentares de quatorze espécies fitófagas de Coleoptera, Lepidoptera e Hemiptera sobre aproximadamente cinqüenta espécies de Piperaceae observadas em São Paulo, SP, Brasil, durante um período de quatro anos.


Assuntos
Animais , Besouros/fisiologia , Hemípteros/fisiologia , Lepidópteros/fisiologia , Piper/parasitologia , Brasil , Interações Hospedeiro-Parasita
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