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1.
Chem Biodivers ; : e202400670, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38747034

RESUMO

Cancer remains a significant global health concern, with mortality rates steadily rising and prompting an urgent search for effective treatments. This study focuses on the medicinal properties of plants from the Phyllanthus genus, specifically Phyllanthus amarus and Phyllanthus niruri, which have shown promise in traditional medicine. Through bioguided fractionation using preparative high-performance liquid chromatography (HPLC), bioactive compounds were isolated and identified using ultra-performance liquid chromatography coupled to time-of-flight mass spectrometry (UHPLC-QTOF-MSE) and nuclear magnetic resonance (NMR) spectroscopy. Chemometric analyses such as principal component analysis (PCA) aided in understanding metabolite distribution. Biological assays demonstrated cytotoxic activities of specific fractions against cancer cell lines, notably the PhyN 4n fraction from P. niruri, which induced S-phase cell cycle arrest and apoptosis in HL60 cells. These findings underscore the anticancer potential of Phyllanthus species and lay the groundwork for future drug development efforts. The study's integration of advanced analytical techniques, chemometrics, and biological assays provides valuable insights for harnessing natural products in the fight against cancer.

2.
J Chem Ecol ; 48(7-8): 660-669, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35653012

RESUMO

In most commercial pine farms in southern Brazil, black capuchin causes damage to wood and financial losses when it removes bark from some pine species to feed upon underlying vascular tissues. Therefore, this study aimed to evaluate the variability of the primary metabolites of phloem saps from 10 different species of pine by NMR spectroscopy, as well as the aroma compounds using SPME-GC-MS. Each technique provided a different set of metabolites that we can correlate to monkey predilection. The PCA showed monosaccharide (detected by NMR) and α-pinene (pine-like and resinous flavor descriptors) as attractive compounds for monkeys. On the other hand, the low content of monosaccharide and the high content of ß-phellandrene (citrus odor descriptor) was observed in less attacked pine species (P. patula). The data fusion on primary metabolites and aroma compounds corroborated the individual analyses, complementing the comprehension of the monkey predilection. Thus, P. elliottii was an avoided tree even with high content of sugars possibly due to its high content of ß-phellandrene (citrus odor). The results are useful for further behavioral studies to determine the role that each highlighted metabolite plays in chemically mediated animal-plant interactions.


Assuntos
Citrus , Pinus , Animais , Citrus/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Monossacarídeos/metabolismo , Floema/metabolismo , Pinus/química , Sapajus
3.
Food Chem ; 372: 131207, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34634585

RESUMO

Se is an essential element in mammals. We review how its bioavailability in soil and the ability of plants to accumulate Se in foods depends on the soil Se profile (including levels and formats), besides to describe how the various selenoproteins have important biochemical functions in the body and directly impact human health. Owing to its favorable characteristics, the scientific community has investigated selenomethionine in most nut matrices. Among nuts, Brazil nuts have been highlighted as one of the richest sources of bioavailable Se. We summarize the most commonly used analytical methods for Se species and total Se determination in nuts. We also discuss the chemical forms of Se metabolized by mammals, human biochemistry and health outcomes from daily dietary intake of Se from Brazil nuts. These findings may facilitate the understanding of the importance of adequate dietary Se intake and enable researchers to define methods to determine Se species.


Assuntos
Bertholletia , Selênio , Humanos , Nozes , Avaliação de Resultados em Cuidados de Saúde , Selenoproteínas
4.
Carbohydr Polym ; 261: 117829, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33766334

RESUMO

In this study, a polysaccharide from marine alga Acanthophora spicifera (PAs) was isolated and structurally characterized. Its protective potential against chemically-induced gastric mucosa injury was evaluated. The gel permeation chromatography experiments and spectroscopy spectrum showed that PAs is a sulfated polysaccharide with a high molecular mass (6.98 × 105g/mol) and degree of sulfation of 1.23, exhibiting structural characteristic typical of an agar-type polysaccharide. Experimental results demonstrated that PAs reduced the hemorrhagic gastric injury, in a dose-dependent manner. Additionally, PAs reduced the intense gastric oxidative stress, measured by glutathione (GSH) and malondialdehyde (MDA) levels. PAs also prevented the reduction of mucus levels adhered to the gastric mucosa, promoted by the aggressive effect of ethanol. In summary, the sulfated polysaccharide from A. spicifera protected the gastric mucosa through the prevention of lipid peroxidation and enhanced the defense mechanisms of the gastric mucosa, suggesting as a promising functional food as gastroprotective agent.


Assuntos
Citoproteção/efeitos dos fármacos , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/lesões , Polissacarídeos/farmacologia , Rodófitas/química , Ágar/isolamento & purificação , Ágar/farmacologia , Animais , Mucosa Gástrica/patologia , Masculino , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Rodófitas/metabolismo , Estômago/efeitos dos fármacos , Estômago/lesões , Estômago/patologia , Úlcera Gástrica/patologia , Úlcera Gástrica/prevenção & controle , Sulfatos/química , Sulfatos/farmacologia
5.
Food Res Int ; 138(Pt A): 109759, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33292941

RESUMO

Egletes viscosa is a Brazilian medicinal herb consumed as flower bud tea due to its gastroprotective properties. This plant possesses two essential oil-based chemical varieties: trans-pinocarveyl acetate-rich chemotype A and cis-isopinocarveyl acetate- rich chemotype B. Therefore, we developed two simple, fast and reliable methods for discrimination of E. viscosa chemotypes using NIR and 1H qNMR spectroscopies combined with the chemometrics tools (iPLS and PLS-DA). Both methods showed high sensitivity, precision and specificity in the cross-validation tests. The NIR method has the advantages of being non-destructive and analyzable by portable devices, enabling its application for field and industrial evaluations. Meanwhile, the 1H qNMR method allows the quantification of the bioactive components ternatin, tanabalin, and centipedic acid. These aforementioned compounds were found higher in the chemotype A. Accordingly, our methods showed to be complimentary approaches for authenticity and/or quality control of E. viscosa-derived raw materials and herbal products.


Assuntos
Asteraceae , Óleos Voláteis , Plantas Medicinais , Brasil , Extratos Vegetais
6.
Food Chem ; 298: 124958, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260992

RESUMO

This manuscript is a bibliographic review about analyses of different classes of pesticide in fruits using QuEChERS as sample preparation methodology. The aim is to clarify different trends and facilitate decision-making by the scientific community in order to carry out further studies in this field. It is well known that different countries have different pesticides regulations for maximum level of pesticide residue permitted. The comparative analysis amongst the main producer countries reveals that for some fruits they are not studied enough. Recent improvements to QuEChERS make it possible to minimize the pesticides instability due the matrix pH, and achieving cleaner extracts. Regarding the detection systems, the tandem MS are preferred once they have high sensitivity and selectivity, although traditional techniques (GC-ECD and HPLC-DAD) are still commonly used due to their accessibility and good sensitivity to some pesticides. Also, studies involving metabolites usually show that they are more toxic than their precursor compounds.


Assuntos
Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Frutas/química , Praguicidas/análise , Cromatografia Líquida de Alta Pressão , Resíduos de Praguicidas/análise , Espectrometria de Massas em Tandem/métodos
7.
Food Chem ; 289: 558-567, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30955648

RESUMO

São Francisco River Valley (SFRV) is a wine-producing semi-arid region in Brazil. Therefore, we used a 1H NMR and UPLC-MS-based metabolomic approach coupled to chemometrics to evaluate the variability in Chenin Blanc and Syrah wines for two harvest seasons, two vine training system and six rootstocks. Overall, the secondary metabolites were influenced by the three factors studied, whereas the primary metabolites were only by the seasonality. Chenin Blanc wines made in December presented higher content of an unidentified carbohydrate. In Syrah wines, glycerol, tartaric acid, succinic acid and 2,3-butanediol were greater in December, while proline and lactic acid were more abundant in July. For training system, caffeic acid derivatives were increased in wines produced from espalier. Lyre system increased phenolic compounds, organic acids and apocarotenoids. The effect of the rootstocks was less pronounced, affecting basically caffeic acid derivatives. Thus, we expect that our results may assist the winemakers to improve the SFRV wine quality.


Assuntos
Agricultura/métodos , Espectroscopia de Ressonância Magnética/métodos , Espectrometria de Massas/métodos , Vinho/análise , Brasil , Cromatografia Líquida/métodos , Análise de Alimentos/métodos , Metabolômica/métodos , Fenóis/análise , Estações do Ano , Metabolismo Secundário , Vitis/química , Vitis/metabolismo
8.
Chem Biodivers ; 16(6): e1900050, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30980460

RESUMO

The development of studies on emissions of volatile organic compounds (VOCs) by inflorescence of oil palms deserves a special attention regarding the importance to reproduction success and for increase of production. This study aimed to evaluate metabolic profiling of VOCs expelled by male and female inflorescences of different oil palm species (African oil palm, Amazonian Caiaué and the interspecific hybrid BRS-Manicoré), associating the composition variability with main pollinators to improve the comprehension of the plant-insect relationship. The phenylpropanoids, terpenoids and the aliphatic hydrocarbons were predominant classes detected in inflorescences of oil palms and the major compound was estragole. This result may be correlated with attraction of Elaidobius pollinators, since these insects were not attracted by Caiaué, which emitted estragole only in trace amounts. However, Caiaué and the hybrid species were visited by other native species whose frequencies were low and their success as pollinators could not be expected.


Assuntos
Óleo de Palmeira/química , Compostos Orgânicos Voláteis/química , Animais , Arecaceae/química , Arecaceae/metabolismo , Comportamento Animal/efeitos dos fármacos , Análise por Conglomerados , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Hidrocarbonetos/química , Hidrocarbonetos/farmacologia , Masculino , Óleo de Palmeira/metabolismo , Polinização , Terpenos/química , Terpenos/farmacologia , Compostos Orgânicos Voláteis/metabolismo , Compostos Orgânicos Voláteis/farmacologia , Gorgulhos/fisiologia
9.
Sci Rep ; 8(1): 15141, 2018 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-30310165

RESUMO

The Phyllanthus genus is widely distributed in tropical and subtropical areas of the world and present several pharmacological applications. Drought is a restrictive factor for crop development and production, and is becoming a severe problem in many regions of the world. The species Phyllanthus amarus and Phyllanthus niruri were subjected to drought stress for varying periods of time (0, 3, 5, 7, and 10 days), and afterwards, leaves were collected and evaluated for physiological and biochemical responses, such as oxidative stress markers and drought-associated defense mechanisms. Results show that P. amarus has an endogenously higher level of variables of the oxidative/antioxidant metabolism, and P. niruri presents the most significant changes in those variables when compared to control and stressed plants. For both Phyllanthus species, drought stress induces higher levels of organic acids such as malic, succinic, and citric acids, and amino acids such as proline, GABA, alanine, and valine. Moreover, P. niruri plants respond with greater glucose and corilagin contents. Therefore, considering the evaluated metabolic changes, P. amarus is better adapted to drought-stress, while P. niruri presents an acclimation strategy that increases the corilagin levels induced by short-term drought stress.


Assuntos
Adaptação Biológica , Secas , Phyllanthus/fisiologia , Estresse Fisiológico , Antioxidantes/metabolismo , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Metabolômica/métodos , Estresse Oxidativo
10.
Talanta ; 180: 329-336, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29332819

RESUMO

The genus Ocimum (Labiatae) comprises 30 species found in tropical and subtropical regions of the planet, of which species O. basilicum L. and O. gratissimum are widely used in food and traditional medicine. Phytochemical studies on Ocimum have revealed a number of essential oil chemotypes, for example, eugenol, methyl chavicol, linalool, and methyl cinnamate. Since essential oils are commercially assessed according to their content, the aim of this study was to develop a simple and precise method for their qualitative and quantitative analysis using NMR spectroscopy combined with chemometrics. Seven essential oils from different species of Ocimum, an unknown sample, and a commercial sample were evaluated and the results compared to those from established and precise GC-MS and GC-FID methods. Chemometric evaluation from both 1H NMR and GC-MS data revealed three chemotypes: eugenol for O. gratissimum, O. micranthum, and O. tenuiflorum; estragole for O. basilicum, O. basilicum var. purpuracens, and O. selloi; and methyl cinnamate for O. americanum. The unknown and commercial species were classified as cinnamate and eugenol chemotypes, respectively. Despite the corroborating results, the chemometric analysis revealed the higher robustness (better adjustment) of the 1H NMR model compared to the GC-MS method in terms of certain statistical parameters. The 1H NMR method allows for the detection and quantification of organic compounds in a complex mixture without the need for certified standard compounds. Although GC-MS and GC-FID were able to detect five compounds not observed by NMR spectroscopy, the four most important metabolites (eugenol, estragole, methyl cinnamate, and eucalyptol) were more readily detected and quantified by 1H NMR.


Assuntos
Cromatografia Gasosa/métodos , Espectroscopia de Ressonância Magnética/métodos , Ocimum/química , Óleos Voláteis/análise , Óleos de Plantas/análise , Monoterpenos Acíclicos , Derivados de Alilbenzenos , Anisóis/análise , Cinamatos/análise , Cicloexanóis/análise , Eucaliptol , Eugenol/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Monoterpenos/análise
11.
Chemosphere ; 91(5): 586-93, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23332877

RESUMO

New assays with HepG2 cells indicate that Indigo Carmine (IC), a dye that is widely used as additive in many food and pharmaceutical industries exhibited cytotoxic effects. This work describes the development of a bicomponent nanostructured Ti/TiO2/WO3 electrode prepared by "template" method and investigates its efficiency in a photoelectrocatalytic method by using visible light irradiation and applied potential of 1V. After 2h of treatment there are reduction of 97% discoloration, 62% of mineralization and formation of three byproducts assigned as: 2-amine-5-sulfo-benzoic acid, 2,3-dioxo-14-indole-5-sulfonic acid, and 2-amino-α-oxo-5-sulfo-benzeneacetic acid were identified by HPLC-MS/MS. But, cytotoxicity was completely removed after 120 min of treatment.


Assuntos
Eletrodos , Indóis/análise , Nanoestruturas/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Índigo Carmim , Indóis/química , Indóis/toxicidade , Modelos Químicos , Óxidos/química , Processos Fotoquímicos , Titânio/química , Tungstênio/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade
12.
Neotrop. entomol ; 35(2): 264-268, Mar. -Apr. 2006. graf
Artigo em Português | LILACS | ID: lil-431911

RESUMO

Os objetivos deste trabalho foram avaliar os efeitos imediato e latente da temperatura do grão, durante a pulverização, sobre a persistência e eficácia biológica do inseticida bifentrina, no controle de Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae) e Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae). Para tal, bifentrina foi pulverizada em grãos de milho com diferentes temperaturas (25, 30, 35, 40 e 45°C). Para avaliação da sua persistência fez-se a extração e análise do resíduo a cada 30 dias, iniciando logo após a pulverização do inseticida, até os 90 dias de armazenamento. Para avaliação da eficácia biológica, 20 adultos de cada espécie foram colocados em placasde-petri contendo grãos tratados, sendo mantidas em câmaras do tipo B.O.D., a 27 °C e 55 por cento de UR durante 48 horas. Estas avaliações foram realizadas em intervalos de 15 dias, com início logo após a pulverização e término aos 90 dias de armazenamento. Observou-se que tanto a persistência quanto a eficácia biológica da bifentrina reduziram à medida que o período de armazenamento e a temperatura do grão aumentaram. Observou-se, ainda, que S. zeamais apresentou maior tolerância à bifentrina, que T. castaneum.


Assuntos
Animais , Inseticidas/farmacologia , Piretrinas/farmacologia , Temperatura , Tenebrio/efeitos dos fármacos , Gorgulhos/efeitos dos fármacos , Zea mays/parasitologia
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