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1.
Braz J Biol ; 83: e242439, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34468507

RESUMO

Plinia cauliflora (Mart.) Kausel, popularly known as jabuticaba, is rich in polyphenols. Phenolic compounds exhibit several biological properties, which reflect on biomarkers such as biochemical parameters. In the present study, we evaluated the plasmatic levels of glucose, total cholesterol, HDL-cholesterol, triglycerides, and uric acid of Chinese hamsters fed for 45 days with a regular diet or cholesterol-enriched diet supplemented with a liquid extract obtained from P. cauliflora fruits residues standardized in ellagic acid and total phenolic compounds. The results showed that the concentrated extract obtained from jabuticaba residues increased the glycemia of animals fed with a regular diet and reduced the plasmatic uric acid levels of animals fed with a cholesterol-enriched diet. Since hyperuricemia is considered to be a significant risk factor of metabolic disorders and the principal pathological basis of gout, the liquid extract from P. cauliflora fruits residues would be a promising candidate as a novel hypouricaemic agent for further investigation.


Assuntos
Frutas , Myrtaceae , Animais , Cricetinae , Cricetulus , Fenóis , Extratos Vegetais
2.
Sci Rep ; 11(1): 11339, 2021 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-34059725

RESUMO

The emergence of polymyxin resistance in Gram-negative bacteria infections has motivated the use of combination therapy. This study determined the mutant selection window (MSW) of polymyxin B alone and in combination with meropenem and fosfomycin against A. baumannii strains belonging to clonal lineages I and III. To evaluate the inhibition of in vitro drug resistance, we investigate the MSW-derived pharmacodynamic indices associated with resistance to polymyxin B administrated regimens as monotherapy and combination therapy, such as the percentage of each dosage interval that free plasma concentration was within the MSW (%TMSW) and the percentage of each dosage interval that free plasma concentration exceeded the mutant prevention concentration (%T>MPC). The MSW of polymyxin B varied between 1 and 16 µg/mL for polymyxin B-susceptible strains. The triple combination of polymyxin B with meropenem and fosfomycin inhibited the polymyxin B-resistant subpopulation in meropenem-resistant isolates and polymyxin B plus meropenem as a double combination sufficiently inhibited meropenem-intermediate, and susceptible strains. T>MPC 90% was reached for polymyxin B in these combinations, while %TMSW was 0 against all strains. TMSW for meropenem and fosfomycin were also reduced. Effective antimicrobial combinations significantly reduced MSW. The MSW-derived pharmacodynamic indices can be used for the selection of effective combination regimen to combat the polymyxin B-resistant strain.

3.
Planta Med ; 86(4): 276-283, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31968379

RESUMO

The treatment of vitiligo includes the combination of psoralens and ultraviolet type A exposure. Psoralens belong to a group of natural furanocoumarins that cause the skin to become sensitive temporarily to ultraviolet type A. The aim of this study was to develop a physiologically based pharmacokinetic model of 5-MOP from Brosimum gaudichaudii to support psoralen and ultraviolet type A therapy. A study of rats was used to establish and validate rat tissue distribution. The same chemical-specific parameters used in the rat model were also employed in the human model to project human pharmacokinetics. The highest exposures in the rats were in the brain and skin. Following a single dose of 1.2 mg/kg 5-MOP in humans, the model predicted a maximum concentration of 20 ng/mL and an area under the curve of 125 ng.h/mL, matching clinical results. The half-maximum melanogenesis concentrations in B16F10 cells were 29.5, 18.5, 11.5, and 6.5 ng/mL for synthetic 5-MOP, synthetic 5-MOP with ultraviolet type A, B. gaudichaudii alone, and B. gaudichaudii plus ultraviolet type A, respectively. Physiologically based pharmacokinetic model prediction in humans supported a once-every-two-day regimen for optimal melanin production. This type of framework can be applied to support strategies for dose selection and to investigate the impact of drugs on melanocyte recovery.


Assuntos
Furocumarinas , Moraceae , 5-Metoxipsoraleno , Animais , Humanos , Metoxaleno , Fitoterapia , Ratos
4.
Pharmacogn Mag ; 12(45): 9-12, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27019555

RESUMO

BACKGROUND: Myrcia amazonica. DC is a species predominantly found in northern Brazil, and belongs to the Myrtaceae family, which possess various species used in folk medicine to treat gastrointestinal disorders, infectious diseases, and hemorrhagic conditions and are known for their essential oil contents. MATERIALS AND METHODS: This study aimed applied the Box-Behnken design combined with response surface methodology to optimize ultrasound-assisted extraction of total polyphenols, total tannins (TT), and total flavonoids (TF) from M. amazonica DC. RESULTS: The results indicated that the best conditions to obtain highest yields of TT were in lower levels of alcohol degree (65%), time (15 min), and also solid: Liquid ratio (solid to liquid ratio; 20 mg: 5 mL). The TF could be extracted with high amounts with higher extraction times (45 min), lower values of solid: Liquid ratio (20 mg: mL), and intermediate alcohol degree level. CONCLUSION: The exploitation of the natural plant resources present very important impact for the economic development, and also the valorization of great Brazilian biodiversity. The knowledge obtained from this work should be useful to further exploit and apply this raw material. SUMMARY: Myrcia amazonica leaves possess phenolic compounds with biological applications;Lower levels of ethanolic strength are more suitable to obtain a igher levels of phenolic compouds such as tannins;Box-Behnken design indicates to be useful to explore the best conditions of ultrasound assisted extraction. Abbreviation used: Nomenclature ES: Ethanolic strength, ET: Extraction time, SLR: Solid to liquid ratio, TFc: Total flavonoid contents, TPc: Total polyphenol contents, TTc: Total tannin contents.

5.
Pharmacogn Mag ; 11(42): 368-73, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25829777

RESUMO

BACKGROUND: The extraction method of bioactive compounds is an important step in the manufacturing of herbal medicines, because secondary metabolites with therapeutic potential are usually found in small quantities in plant materials. OBJECTIVE: Due the potential of Apeiba tibourbou Aubl, this study aimed to evaluate the impact of the extraction method on the quality of herbal extract and optimize the extraction of fatty acid, rosmarinic (Ra) and caffeic (Ca) acid from A. tibourbou. MATERIALS AND METHODS: Determinations of residual moisture (Rm), proteins (Pt), lipids (Lp), total fiber (Tf), and carbohydrate (Cy) were performed in triplicate samples according assessment of antioxidant capacity. Extraction of fatty acids was carried out by two different methods: (i) By shoxlet and (ii) bligh and dyer. The optimized conditions were determined by surface response methodology (RSM), and the criterion of desirability was the maximum extraction of Ra and Ca. RESULTS: The method of bligh and dyer was able to extraction more total Lp than the shoxlet. However, the extraction of fatty acid was different for the two methods. The optimized conditions to extract RA and Ca was calculated by RSM, 42°C, 30% (alcohol degree) and 24 min, this conditions maximize simultaneously the extraction of Ca (0, 04%) and Ry (1.89). CONCLUSION: It was observed that the extraction method alters the chemical composition of extract, and it is possible to extract Ca and Ra from A. tibourbou's leaves using ultrasound-assisted extraction.

6.
Pharmacogn Mag ; 11(41): 170-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25709229

RESUMO

BACKGROUND: The standardized liquid extract of Brosimum gaudichaudii Trécul is an alternative for the treatment of vitiligo. There is a shortage of solid oral dosage forms developed from standardized extracts of this plant specie. OBJECTIVE: This study is aimed to obtain pellets with a standardized liquid extract of B. gaudichaudii. RESULTS: The standardized liquid extract of B. gaudichaudii was obtained through maceration and percolation with a 55% ethanol-water solution (v/v). Pellets were obtained through a mixture of extract of 500 g of B. gaudichaudii standardized extract, 500 g of microcrystalline cellulose PH101 and 10 g of hydroxypropyl methylcellulose K100. The pellets obtained presented a homogeneity yield of 92%, aspect ratio of 1.16 ± 0.65, shape fator e R of 0.35 ± 0.09 and Feret diammeter of 0.87 ± 0.27. These pellets were coated with a suspension composed of titanium dioxide, aluminum red lacquer, ethyl cellulose, talc and magnesium stearate. Before the photostability test, the uncoated pellets showed psoralen content equal to 0.13 ± 0.01% and to the 5-MOP was 1.40 ± 0.27%. After exposure to one level (3 J.cm(-2)) of UVB irradiation the uncoated pellets presented a degradation of 2.16% of psoralen and 8.1% of 5-MOP. After exposure to three levels (10, 20 and 30 J.cm(-2)) of UVA irradiation the uncoated pellets exhibited photodegradation of 9.78, 17.64, 24.21% of psoralen and 18.95, 23.68, 28.48% for 5-MOP. The coated pellets where unaffected after photostability test. CONCLUSION: Pellets were obtained with the standardized liquid extract of B. gaudichaudii and coating is a technological alternative to ensure the stability of the formula.

7.
Pharmacogn Mag ; 11(41): 226-31, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25709236

RESUMO

INSTRUCTION: Despite the increased use of Brosimum gaudichaudii roots as raw material on medicine to treatment of vitiligo, there are not studies that showing the impact of unit operations on the quality and standardized of the extract of B. gaudichaudii. The quality of the herbal extract is essential to ensure the safety and efficacy of pharmaceutical product. Due the medical and commercial importance, this study aimed to evaluate the impact of the extraction method (ultrasound or percolation) on the quality of herbal extract and optimize the extraction of psoralen and 8-methoxypsoralen (8-MOP) from B. gaudichaudii. MATERIALS AND METHODS: The extraction recovery was evaluate by high-performance liquid chromatography (C8 reverse phase column and acetonitrile: Water 45:55 and flow rate 0.6 mL/min). The extraction was performed by ultrasound-assisted extraction (UEA) or percolation using a Box-Behnken design. RESULTS: From both chemical markers (psoralen and bergapten), the optimal conditions for the UEA were an extraction time of 25 min, the mean particle size of 100 µm, and an ethanol: Water ratio of 55:45 (v/v). CONCLUSION: The extraction by percolation revealed that ethanol 55% was more efficient than ethanol 80% to extract psoralen and bergapten.

8.
Pharmacogn Mag ; 10(Suppl 3): S569-73, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25298676

RESUMO

BACKGROUND: Calendula officinalis L. (Asteraceae) is a Mediterranean specie, but in Europe and America it is cultivated for ornamental or medicinal purposes. This species is widely used for presenting activities, antiinflammatory antibacterial and antioxidant. However the therapeutic action is linked to the amount of assets of the extracted raw material. The extraction method of bioactive compounds is an important step in the manufacturing of herbal medicines, because secondary metabolites with therapeutic potential are usually found in small quantities in plant materials. OBJECTIVE: Due the medical and commercial importance of C. officinalis, this study aimed to evaluate the impact of the extraction method on the quality of herbal extract and optimize the extraction of rutin from C. officinalis. MATERIALS AND METHODS: The extraction of rutin was performed by ultrasound and shaker and the optimized conditions were determined by response surface methodology. RESULTS: The results of ultrasound extraction assisted (UEA) and maceration dynamic (MD) showed that rutin yield ranged from 0.218 to 2.28% (w/w) when extract by ultrasound and 0.1-1.44% by MD. The optimal extraction condition for rutin (2.48% to UEA or 1.46% to MD) from C. officinalis by UEA or MD were a 19-22 min extraction, ethanol: water ratio of 35-40% and 0.05-0.056 mg/mL to raw material: solvent ratio. CONCLUSION: The UEA is more efficient to extraction rutin.

9.
J Ethnopharmacol ; 139(2): 319-29, 2012 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-21549815

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Synadenium umbellatum Pax. is widely found in South America and empirically used in Brazil for the treatment of several diseases, mainly cancer. The aim of the study was to investigate cell death mechanisms induced by Synadenium umbellatum Pax. using Ehrlich ascites tumor (EAT) cells, as well as the myelotoxicity potential of this plant. MATERIALS AND METHODS: S. umbellatum cytotoxicity was evaluated in EAT cells by trypan blue exclusion and MTT reduction test and the mechanisms involved in EAT cell death were investigated by light and fluorescence microscopy, flow cytometry and immunocytochemistry. Investigation of S. umbellatum myelotoxicity was performed by clonogenic assay of colony forming unit- granulocyte macrophage (CFU-GM). RESULTS AND CONCLUSION: Our results demonstrated that S. umbellatum decreased the viability of EAT cells using both methods. Morphological analyses revealed that S. umbellatum-treatment induced EAT cell death by apoptotic pathway. We demonstrated the occurrence of reactive oxygen species (ROS) overgeneration, increased intracellular Ca(2+) concentration, alteration in mitochondrial membrane potential, phosphatydylserine externalization, and activation of caspases 3, 8, and 9. However, S. umbellatum produced myelotoxicity in bone marrow cells in a concentration-dependent manner. In comparison to EAT cells, the effects of S. umbellatum in bone marrow cells were 8-fold lower. Taken together, our results showed that S. umbellatum induced apoptosis in EAT cells at several levels and seems more toxic to tumor cells than to normal bone marrow cells.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma de Ehrlich/patologia , Euphorbiaceae , Animais , Antineoplásicos Fitogênicos/toxicidade , Cálcio/metabolismo , Carcinoma de Ehrlich/metabolismo , Caspase 3/metabolismo , Caspase 8/metabolismo , Caspase 9/metabolismo , Ciclo Celular/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Citometria de Fluxo , Células Progenitoras de Granulócitos e Macrófagos/efeitos dos fármacos , Células Progenitoras de Granulócitos e Macrófagos/patologia , Imuno-Histoquímica , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Microscopia de Fluorescência , Estresse Oxidativo/efeitos dos fármacos , Fosfatidilserinas/metabolismo , Componentes Aéreos da Planta , Plantas Medicinais , Espécies Reativas de Oxigênio/metabolismo , Células Tumorais Cultivadas
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