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1.
Phytochem Anal ; 35(3): 552-566, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38191126

RESUMO

INTRODUCTION: In Brazil, the plant group popularly known as "pedra-ume-caá" is used in folk medicine for the treatment of diabetes, and its raw material is commonly sold. OBJECTIVE: The aim of the study was to apply a method for chemical identification of extracts of dry pedra-ume-caá leaves using HPLC-high-resolution mass spectrometry (HRMS) and NMR and develop a multivariate model with NMR data to authenticate commercial samples. In addition, to evaluate the biological activities of the extracts. MATERIALS AND METHODS: Dry extracts of Myrcia multiflora, Myrcia amazonica, Myrcia guianensis, Myrcia sylvatica, Eugenia punicifolia leaves, and 15 commercial samples (sold in Manaus and Belém, Brazil) were prepared by infusion. All the extracts were analysed using HPLC-high-resolution mass spectrometry (HRMS), NMR, principal component analysis (PCA), and hierarchical cluster analysis (HCA). The antidiabetic effect of extracts was evaluated according to enzymatic inhibition. Their content of total phenols, cell viability, and antioxidant and antiglycation activities were also determined. RESULTS: HPLC-HRMS and NMR analysis of these extracts permitted the identification of 17 compounds. 1H NMR data combined with multivariate analyses allowed us to conclude that catechin, myricitrin, quercitrin, and gallic and quinic acids are the main chemical markers of pedra-ume-caá species. These markers were identified in 15 commercial samples of pedra-ume-caá. Additionally, only the extracts of M. multiflora and E. punicifolia inhibited α-glucosidase. All the extracts inhibited the formation of advanced glycation end products (AGEs) and showed free-radical-scavenging activity. These extracts did not present cytotoxicity. CONCLUSION: This study revealed the chemical markers of matrices, and it was possible to differentiate the materials marketed as pedra-ume-caá. Moreover, this study corroborates the potential of these species for treating diabetes.


Assuntos
Diabetes Mellitus , Myrtaceae , Antioxidantes/química , Extratos Vegetais/química , Myrtaceae/química , Espectroscopia de Ressonância Magnética , Folhas de Planta/química
2.
J Ethnopharmacol ; 293: 115276, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35421528

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The leaves of Eugenia biflora (Myrtaceae) are traditionally used by Amazonian populations for the control of diabetes. However, their chemical composition has not yet been described and pharmacological evidence has not been reported. OBJECTIVE: This study aimed to identify the chemical constituents and evaluate the hypoglycemic and toxic effect of the dry extract of the E. biflora leaves (DEEB). MATERIALS AND METHODS: DEEB, obtained by infusion, was analyzed using LC-HRMS and NMR, whose the catechin flavonoid was quantified using NMR. The antidiabetic effect of DEEB was evaluated according to its inhibition of the enzymes α-amylase and α-glucosidase, as well as the content of total phenols, free radical scavengingand antiglycation activities, and its in vitro cell viability. Oral maltose tolerance and chronic multiple dose tests (28 days) in streptozotocin-induced diabetic mice (STZ) were performed. The hypoglycemic effect and toxicity of this extract were evaluated in the multiple dose assay. Biochemical parameters, hemolysis, and levels of the thiobarbituric acid reactive species in the liver were investigated and histopathological analyses of the kidneys and liver were performed. RESULTS: Eight phenolic compounds were identified, with catechin (15.5 ± 1.7 mg g-1) being the majority compound and a possible chemical marker of DEEB. The extract showed inhibition activity of the enzyme α-glucosidase. Chronic administration of DEEB (50 mg/kg of body weight) reduced glucose levels in diabetic animals, similar to acarbose; however, DEEB (100 and 200 mg/kg bw) caused premature death of mice by D22 of the treatment. Our data indicate that one of the mechanisms of toxicity in DEEB may be related to the aggravation of oxidative stress in the liver. This histopathological study indicated that DEEB failed to minimize the progression of the toxicity of diabetes caused by STZ. CONCLUSIONS: This study demonstrated the hypoglycemic potential of E. biflora leaves. However, the prolonged use of this tea can be harmful to its users due to its considerable toxicity, which needs to be better investigated.


Assuntos
Diabetes Mellitus Experimental , Eugenia , Hipoglicemiantes , Animais , Antioxidantes/farmacologia , Glicemia , Catequina , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Eugenia/química , Hipoglicemiantes/uso terapêutico , Hipoglicemiantes/toxicidade , Camundongos , Extratos Vegetais/uso terapêutico , Extratos Vegetais/toxicidade , Folhas de Planta/química , Estreptozocina , alfa-Glucosidases/metabolismo
3.
J Pharm Biomed Anal ; 201: 114109, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33957365

RESUMO

Myrcia multiflora (Lam.) DC. is often used in Brazilian folk medicine to control diabetes. Analysis using HPLC-HRMS and NMR of the dry extract from the infusion of leaves of this species revealed twelve phenolic compounds. Among these compounds, chlorogenic acid (1), 4-O-caffeoylquinic acid (2), corilagin (3), chebulagic acid (4), pedunculagin (5), quercetin-3-O-ß-2″-galloylglucoside (7), and kaempferol-3-O-rhamnoside (12) are described for the first time in this matrix. Furthermore, six compounds were quantified using qNMR. The compounds in the dry extracts are 3, 6 (myricetin-3-O-d-glucoside), 8 (myricitrin), 9 (hyperoside), 10 (guaijaverin) and 11 (quercitrin). These compounds may be considered chemical markers in this matrix. In addition, this extract presents activities of α-glucosidase inhibition (IC50 = 79.9 µg mL-1) and glycation in vitro (IC50 = 10.2 µg mL-1), in addition to antioxidant activity against DPPH and ABTS radicals (1,856.7 and 1,032.0 µmol TEq, respectively). This extract did not show significant cytotoxicity in human fibroblasts. Therefore, the enzymatic inhibition, anti-AGE (advanced glycation end-products) and antioxidant activities of Myrcia multiflora leaves corroborated its antidiabetic therapeutic potential and instigates future preclinical studies aimed at the treatment of diabetes mellitus and its complications.


Assuntos
Antioxidantes , Myrtaceae , Antioxidantes/farmacologia , Brasil , Humanos , Extratos Vegetais/farmacologia , Folhas de Planta
4.
Food Res Int ; 123: 674-683, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31285017

RESUMO

Species of Eugenia have been used as an antidiabetic natural source. Chemical, antioxidant and antiglycant screening of extracts from pedra-ume caá (Eugenia punicifolia) fruits were performed. 1H NMR assisted by non-supervised chemometric methods were employed for the evaluation of the chemical profiles which were distinguished according to the color of fruit maturation stages, as well as for pulp and seed fruit. Furthermore, 1H NMR fingerprint analysis of the crude extract allowed the identification of quercitrin and myricitrin, beside other nine compounds. The extracts of the yellow (YP) and green (GP) pulps presented higher antiglycant and antioxidant activities. Fresh juice from E. punicifolia was encapsulated in microcapsules produced with dextrose equivalent (DE) of 10, 20 or 30 as wall materials for the maintainment of their antioxidant and antiglycant properties. The more efficient retention of the bioactive compounds was found using the DE30. The Encapsulation Efficiency (EE) and the Retention Efficiency (RE) of this system was found around 89.7% and 97.6%, respectively. In addition, NMR spectra revealed the presence of flavonoids O-glycosylated (quercitrin and myricitrin) which might be related to the antiglycant and antioxidant activities. The YP presented larger content of quercitrin (117.6 ±â€¯0.4 mg per each 100 g of fresh fruit). Therefore, pedra-ume caá should be employed as an alternative nutraceutical source, as well as intherapeutic pourposes.


Assuntos
Antioxidantes/análise , Eugenia/química , Frutas/química , Fenóis/análise , Extratos Vegetais/química , Antioxidantes/farmacologia , Brasil , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Flavonoides/isolamento & purificação , Sequestradores de Radicais Livres , Humanos , Extratos Vegetais/farmacologia , Quercetina/análogos & derivados , Quercetina/isolamento & purificação
5.
Chem Biodivers ; 16(4): e1800547, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30719835

RESUMO

The aim of this study was to evaluate the chemical, antioxidant, and antimicrobial activity of the essential oils as well as the anatomy of the aerial parts from Baccharis aracatubaensis, Baccharis burchellii, and Baccharis organensis owing to the therapeutic potential of Baccharis. The volatile constituents were analyzed using GC/MS, the antioxidant activity was evaluated by oxygen radical absorbance capacity (ORACFL ) and DPPH assays, and the antimicrobial activity by a microdilution technique. Of the 56 compounds identified, only seven (ß-caryophyllene, γ-muurolene, bicyclogermacrene, ß-germacrene, spathulenol, τ-muurolol, and α-cadinol) were common in the three specimens studied. Of these, γ-muurolene was found abundantly in B. aracatubaensis, while bicyclogermacrene was abundant in B. burchellii and B. organensis. The essential oils exhibited antioxidant activity in the ORACFL (>500.0 µmol TE g-1 ) and DPPH assays. However, they did not exhibit any antimicrobial activity. Secretory ducts and flagelliform glandular trichomes were observed in the anatomical study of all the Baccharis species studied.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Antioxidantes/farmacologia , Baccharis/química , Óleos Voláteis/farmacologia , Componentes Aéreos da Planta/química , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antifúngicos/química , Antifúngicos/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Compostos de Bifenilo/antagonistas & inibidores , Candida albicans/efeitos dos fármacos , Relação Dose-Resposta a Droga , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Picratos/antagonistas & inibidores , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Relação Estrutura-Atividade
6.
PLoS One ; 13(4): e0196166, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29694403

RESUMO

The intense use of herbicides for weed control in agriculture causes selection pressure on soil microbiota and water ecosystems, possibly resulting in changes to microbial processes, such as biogeochemical cycles. These xenobiotics may increase the production of reactive oxygen species and consequently affect the survival of microorganisms, which need to develop strategies to adapt to these conditions and maintain their ecological functionality. This study analyzed the adaptive responses of bacterial isolates belonging to the same species, originating from two different environments (water and soil), and subjected to selection pressure by herbicides. The effects of herbicide Callisto and its active ingredient, mesotrione, induced different adaptation strategies on the cellular, enzymatic, and structural systems of two Bacillus megaterium isolates obtained from these environments. The lipid saturation patterns observed may have affected membrane permeability in response to this herbicide. Moreover, this may have led to different levels of responses involving superoxide dismutase and catalase activities, and enzyme polymorphisms. Due to these response systems, the strain isolated from water exhibited higher growth rates than did the soil strain, in evaluations made in oligotrophic culture media, which would be more like that found in semi-pristine aquatic environments. The influence of the intracellular oxidizing environments, which changed the mode of degradation of mesotrione in our experimental model and produced different metabolites, can also be observed in soil and water at sites related to agriculture. Since the different metabolites may present different levels of toxicity, we suggest that this fact should be considered in studies on the fate of agrochemicals in different environments.


Assuntos
Bacillus megaterium/crescimento & desenvolvimento , Cicloexanonas/farmacologia , Herbicidas/farmacologia , Microbiologia do Solo , Microbiologia da Água , Adaptação Fisiológica , Bacillus megaterium/classificação , Bacillus megaterium/efeitos dos fármacos , Bacillus megaterium/genética , Biodegradação Ambiental , Ecossistema , Peroxidação de Lipídeos/efeitos dos fármacos , Viabilidade Microbiana/efeitos dos fármacos , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
7.
Food Res Int ; 75: 315-327, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28454962

RESUMO

The "araçá-pera" (Psidium acutangulum DC) is an exotic guava consumed by the Brazilian Amazon population. This paper describes 22 compounds from this fruit by UHPLC-HRMS and NMR methods, being one disaccharide, five monosaccharides, two organic acids, one trihydroxycinnamic acid glucopyranosyl, one tannine digalloyl glucopyranosyl, five triterpenoid acids, and six fatty acids. It also quantifies the level of ascorbic acid (AA) by HPLC-MS (74.32±1.23mg/100g of fresh fruit), and defines the chemical antioxidant activities by DPPH and ABTS+ assays (24.96±0.75, 90.57±0.63mg of vitamin C/100g fresh fruit, respectively), and a cell-based assays (76-100%). These results have shown that this exotic guava can be consumed as a nutraceutical ingredient, as well as be used in the production of functional foods in the Amazonian diet to prevent chronic and oxidative diseases.

8.
Rev. bras. farmacogn ; 24(6): 609-616, Nov-Dec/2014. graf
Artigo em Inglês | LILACS | ID: lil-741840

RESUMO

Baccharis glaziovii Baker, Asteraceae, also known as carqueja or carqueja-arbustinho, is a native shrub of Brazil that reaches 0.5-2.5 m in height. It is a dioecious species that blossoms from September to December. This species has cladodes, which are winged stems that belong to the “carquejas” and are widely used indiscriminately by the population due to their gastric and diuretic properties. Carquejas are included in section Caulopterae and are difficult to identify even for taxonomists or Baccharis specialists. In the present study, a morpho-anatomical (cladodes and leaves) analysis of the medicinal plant was undertaken to improve its identification and add to the knowledge of section Caulopterae. Fragments of cladodes and leaves were collected and prepared in accordance with standard optical and scanning electron microscopy techniques. The morpho-anatomical characteristics found in B. glaziovii, include three-winged stems showing wings in a regular arrangement around the stem axis, short and petiolate leaves, flagelliform and simple non-glandular trichomes, concave-convex midrib, petioles with a concave shape and a slight projection on the adaxial face and convex with three projections on the abaxial surface, and calcium oxalate crystals in the form of raphides, styloids and pyramidal in the perimedullary region of the cladode, when evaluated as a whole, provide support for the quality control. .

9.
PLoS One ; 9(4): e92851, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24690884

RESUMO

Invasive aspergillosis is an opportunistic infection that is mainly caused by Aspergillus fumigatus, which is known to produce several secondary metabolites, including gliotoxin, the most abundant metabolite produced during hyphal growth. The diagnosis of invasive aspergillosis is often made late in the infection because of the lack of reliable and feasible diagnostic techniques; therefore, early detection is critical to begin treatment and avoid more serious complications. The present work reports the development and validation of an HPLC-MS/MS method for the detection of gliotoxin in the serum of patients with suspected aspergillosis. Chromatographic separation was achieved using an XBridge C18 column (150 × 2.1 mm id; 5 mm particle size) maintained at 25 °C with the corresponding guard column (XBridge C18, 10 × 2.1 mm id, 5 mm particle size). The mobile phase was composed of a gradient of water and acetonitrile/water (95:5 v/v), both containing 1 mM ammonium formate with a flow rate of 0.45 mL min(-1). Data from the validation studies demonstrate that this new method is highly sensitive, selective, linear, precise, accurate and free from matrix interference. The developed method was successfully applied to samples from patients suspected of having aspergillosis. Therefore, the developed method has considerable potential as a diagnostic technique for aspergillosis.


Assuntos
Aspergilose/diagnóstico , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Gliotoxina/sangue , Gliotoxina/química , Humanos , Extração Líquido-Líquido , Quercetina/química , Padrões de Referência , Reprodutibilidade dos Testes , Fatores de Risco , Solventes/química
10.
Phytochemistry ; 95: 375-83, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23937905

RESUMO

Polyacetylenes constitute an underexplored and unstable class of compounds that are found mainly in the Apiaceae, Araliaceae and Asteraceae families. Vernonia scorpioides (Lam.) Pers., Asteraceae is a lianous neotropical herb that usually grows in soils that have been deforested and are of poor quality. It is used in folk medicine for the treatment of several skin conditions. This study addresses the characterisation of eight polyacetylenes isolated from the leaves of V. scorpioides. Their structures were established on the basis of 1D and 2D NMR spectroscopy and MS analysis. Ab initio calculations including solvent effects were employed to aid the elucidation of the absolute configurations of the compounds. The in vitro antiproliferative and anti-herpetic activities of the polyacetylenes were determined. The isolated compounds presented no inhibitory effect against a human cell line of non-small cell lung cancer, but presented a mild non-selective in vitro antiviral activity, although their corresponding glycosides were inactive.


Assuntos
Antivirais/farmacologia , Extratos Vegetais/farmacologia , Poli-Inos/farmacologia , Simplexvirus/efeitos dos fármacos , Vernonia/química , Antivirais/química , Antivirais/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Medicina Tradicional , Estrutura Molecular , Extratos Vegetais/química , Folhas de Planta/química , Poli-Inos/química , Poli-Inos/isolamento & purificação , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico
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