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1.
Molecules ; 29(2)2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38257382

RESUMO

Schinus terebinthifolius Raddi, popularly known as "Pink pepper", is a plant native to Brazil. The objective of this work was to analyze the chemical composition and the antioxidant and antibacterial potential of essential oils (EOs) from the leaves, fruits and twigs of S. terebinthifolius, aiming for their application in food safety. EOs were obtained by hydrodistillation and the chemical composition was determined by gas chromatography coupled to mass spectrometry. Phenolic compounds were quantified and antioxidant activity was evaluated using three different methods. The antibacterial activity was determined by the broth microdilution method against foodborne bacteria. In the chemical analysis, 22 compounds were identified in the leaves, 13 compounds in the fruits and 37 compounds in the twigs, revealing the presence of the main compounds germacrene D (12.04%, 15.78%, 20,41%), caryophyllene (15.97%, 3.12%, 11.73%), α-pinene (11.6%, 17.16%, 2.99%), ß-pinene (5.68%, 43.34%, 5.60%) and γ-gurjunene (16,85%, 3,15%) respectively. EOs showed better antioxidant potential using the ß-carotene/linoleic acid method with 40.74, 61.52 and 63.65% oxidation inhibition for leaves, fruits and twigs, respectively. The EO from the leaves showed greater antibacterial potential against Escherichia coli and Staphylococcus aureus with a minimum inhibitory concentration (MIC) of 0.62 mg mL-1, a value lower than the MIC of sodium nitrite (5.00 mg mL-1), the antimicrobial standard synthetic. The activities of pink pepper EOs suggest their potential as a biopreservative in foods.


Assuntos
Óleos Voláteis , Piper nigrum , Frutas , Antioxidantes/farmacologia , Schinus , Óleos Voláteis/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Antibacterianos/farmacologia , Escherichia coli
2.
PeerJ ; 10: e14313, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36389402

RESUMO

Biodiversity assessment is a mandatory task for sustainable and adaptive management for the next decade, and long-term ecological monitoring programs are a cornerstone for understanding changes in ecosystems. The Brazilian Long-Term Ecological Research Program (PELD) is an integrated effort model supported by public funds that finance ecological studies at 34 locations. By interviewing and compiling data from project coordinators, we assessed monitoring efforts, targeting biological groups and scientific production from nine PELD projects encompassing coastal lagoons to mesophotic reefs and oceanic islands. Reef environments and fish groups were the most often studied within the long-term projects. PELD projects covered priority areas for conservation but missed sensitive areas close to large cities, as well as underrepresenting ecosystems on the North and Northeast Brazilian coast. Long-term monitoring projects in marine and coastal environments in Brazil are recent (<5 years), not yet integrated as a network, but scientifically productive with considerable relevance for academic and human resources training. Scientific production increased exponentially with project age, despite interruption and shortage of funding during their history. From our diagnosis, we recommend some actions to fill in observed gaps, such as: enhancing projects' collaboration and integration; focusing on priority regions for new projects; broadening the scope of monitored variables; and, maintenance of funding for existing projects.


Assuntos
Biodiversidade , Ecossistema , Animais , Humanos , Brasil , Oceanos e Mares , Peixes
3.
Biomed Pharmacother ; 132: 110900, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33113433

RESUMO

Hancornia speciosa is a medicinal plant with proven antihypertensive activity. The cyclitol l-(+)-bornesitol is the main constituent of its leaves and is a potent inhibitor of the angiotensin-converting enzyme. We herein investigated the pharmacokinetic properties of bornesitol administered orally to Wistar rats, as well as bornesitol permeation in Caco-2 cells. Bornesitol was isolated and purified from an ethanol extract of H. speciosa leaves. An ultra-high performance liquid chromatography coupled with electrospray ionization mass spectrometry (UPLC-ESI-MS/MS) method was developed and validated to quantify bornesitol in rat plasma based on Multiple Reaction Monitoring, using pentaerythritol as an internal standard. Pharmacokinetics was evaluated by the administration of single doses via intravenous in bolus (3 mg/kg) and gavage (3, 15 and 25 mg/kg). Bornesitol permeation was assayed in a transwell Caco-2 cells model, tested alone, or combined with rutin, or as a constituent of H. speciosa extract, using a developed and validated UPLC-ESI-MS/MS method. All assayed validation parameters (selectivity, residual effect, matrix effect, linearity, precision, accuracy and stability of analyte in plasma and solution) for the bioanalytical method met the acceptance criteria established by regulatory guidelines. Bornestiol reached peak plasma concentration within approximately 60 min after oral administration with a half-life ranging from 72.15 min to 123.69 min. The peak concentration and area under the concentration-time curve of bornesitol did not rise proportionally with the increasing doses, suggesting a non-linear pharmacokinetics in rats and the oral bioavailability ranged from 28.5%-59.3%. Bornesitol showed low permeability in Caco-2 cells, but the permeability apparently increased when it was administered either combined with rutin or as a constituent of H. speciosa extract. In conclusion, bornesitol was rapidly absorbed after a single oral administration to rats and followed a non-linear pharmacokinetics. The obtained data will be useful to guide further pre-clinical development of bornesitol-containing herbal preparations of H. speciosa as an antihypertensive agent.


Assuntos
Anti-Hipertensivos/farmacocinética , Apocynaceae , Cromatografia Líquida de Alta Pressão , Ciclitóis/farmacocinética , Extratos Vegetais/farmacocinética , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Administração Oral , Animais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/sangue , Anti-Hipertensivos/isolamento & purificação , Apocynaceae/química , Disponibilidade Biológica , Células CACO-2 , Ciclitóis/administração & dosagem , Ciclitóis/sangue , Ciclitóis/isolamento & purificação , Humanos , Injeções Intravenosas , Absorção Intestinal , Mucosa Intestinal/metabolismo , Masculino , Modelos Biológicos , Dinâmica não Linear , Permeabilidade , Extratos Vegetais/administração & dosagem , Extratos Vegetais/sangue , Extratos Vegetais/isolamento & purificação , Ratos Wistar
4.
Int J Pharm ; 587: 119694, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32726610

RESUMO

Furosemide (FSM) is a biopharmaceutical classification system (BCS) class IV drug, being a potent loop diuretic used in the treatment of congestive heart failure and edema. Due to its low solubility and permeability, FSM is known for exhibiting poor oral bioavailability. In order to overcome or even minimize these undesirable biopharmaceutical attributes, in this work we have focused on the development of more soluble and permeable multicomponent solid forms of FSM. Using solvent evaporation as crystallization method, a salt and a cocrystal of FSM with imidazole (IMI) and 5-fluorocytosine (5FC) coformers, named FSM-IMI and FSM-5FC, respectively, were successfully prepared. A detailed structural study of these new solid forms was conducted using single and powder X-ray diffraction (SCXRD, PXRD), Fourier Transform Infrared (FT-IR) and proton Nuclear Magnetic Resonance (1H NMR) spectroscopy and thermal analysis (thermogravimetry, differential scanning calorimetry and hot-stage microscopy). Both FSM-IMI and FSM-5FC showed substantial enhancements in the solubility (up 118-fold), intrinsic dissolution (from 1.3 to 2.6-fold) and permeability (from 2.1 to 2.8-fold), when compared to the pure FSM. These results demonstrate the potential of these new solid forms to increase the limited bioavailability of FSM.


Assuntos
Furosemida , Preparações Farmacêuticas , Varredura Diferencial de Calorimetria , Diuréticos , Permeabilidade , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
5.
Curr Microbiol ; 74(12): 1453-1460, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28840299

RESUMO

Tetradenia riparia (Lamiaceae) is native to Central Africa popularly known as myrrh, used in folk medicine to treat various diseases like malaria, gastroenteritis, and tropical skin disease. This research was to evaluate the antioxidant and antibacterial activities of the crude extract (CE) and fractions (FR) of the T. riparia by classical chromatography. The CE of T. riparia leaves was submitted to column chromatographic fractionation to obtain four fractions of the interest, which were identified by nuclear magnetic resonance and gas chromatograph coupled to mass spectrum: FR-I (abieta-7,9(11)-dien-13-ß-ol), FR-II (Ibozol), FR-III (8 (14), 15-sandaracopimaradiene-2α, 18-diol and 8 (14), 15-sandaracopimaradiene-7α, 18-diol), and FR-IV (Astragalin, Boronolide and Luteolin). Total phenol content of CE and FR were measured, and antioxidant action by methods of DPPH (2,2-diphenyl-1-picrylhydrazyl), ß-carotene/linoleic acid system, and ferric reducing/antioxidant power (FRAP) and the antibacterial activity was evaluated by the broth microdilution method with the determination of the minimum inhibitory concentration (MIC). The FR-IV presented antioxidant potential with 181.67 µg gallic acid/mg, IC50 of 0.61 µg/mL by DPPH method, 55.61% oxidation protection by ß-carotene/linoleic acid system and 4.59 µM ferrous sulfate/mg of sample by FRAP, and the FR-I showed higher antibacterial potential on the strain Staphylococcus aureus with MIC 0.98 µg/mL, Enterococcus faecalis and Bacillus cereus with MIC 31.2 µg/mL. Thus, the fractionation of CE was extremely important to detect fractions with potential activities, and investigations are necessary regarding the mechanism of action and action in vivo.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Lamiaceae/química , Extratos Vegetais/farmacologia , África Central , Antibacterianos/isolamento & purificação , Antioxidantes/isolamento & purificação , Bacillus cereus/efeitos dos fármacos , Brasil , Cromatografia Líquida , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Testes de Sensibilidade Microbiana , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química
6.
Rev. bras. farmacogn ; 27(1): 34-39, Jan.-Feb. 2017. graf
Artigo em Inglês | LILACS | ID: biblio-843782

RESUMO

ABSTRACT Stevia rebaudiana (Bertoni) Bertoni, Asteraceae, is used as a food additive because its leaves are a source of steviol glycosides. There are examples of tissue culture based on micropropagation and phytochemical production of S. rebaudiana leaves but there are few studies on adventitious root culture of S. rebaudiana. More than 90% of the plants used in industry are harvested indiscriminately. In order to overcome this situation, the development of methodologies that employ biotechnology, such as root culture, provides suitable alternatives for the sustainable use of plants. The aim of this study was to compare morpho-anatomical transverse sections of S. rebaudiana roots grown in vitro and in vivo. The in vitro system used to maintain root cultures consisted of a gyratory shaker under dark and light conditions and a roller bottle system. Transverse sections of S. rebaudiana roots grown in vitro were structurally and morphologically different when compared to the control plant; roots artificially maintained in culture media can have their development affected by the degree of media aeration, sugar concentration, and light. GC–MS and TLC confirmed that S. rebaudiana roots grown in vitro have the ability to produce metabolites, which can be similar to those produced by wild plants.

7.
Carbohydr Res ; 411: 15-21, 2015 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-25950401

RESUMO

The polysaccharide inulin has great importance in the food and pharmaceutical industries. The degree of polymerization (DP) of inulin influences important properties, such as, solubility, thermal stability, sweetness power and prebiotic activity. Molecules with a high degree of polymerization are obtained through physical techniques for enrichment of the inulin chains because they are not commonly obtained from plants extract. Gas chromatography/Mass Spectrometry and (1)H Nuclear Magnetic Resonance analysis showed that inulin from Stevia rebaudiana roots has a degree of polymerization (DPn 28) higher than the value of DPn 12-15 for inulins from other plant species. Furthermore, the methodology of freeze/thaw to enrich the chains allowed us to increase the DP, similarly to other methodologies used for the enrichment of inulin chains. The prebiotic assays confirm that inulin from S. rebaudiana has a high DP. The combined use of these molecules with low degree of polymerization fructans seems to be advantageous to prolong the prebiotic effect in the colon. Our results suggest that S. rebaudiana roots are a promising source of high degree polymerization inulins.


Assuntos
Inulina/química , Stevia/química , Bifidobacterium/crescimento & desenvolvimento , Bifidobacterium/metabolismo , Meios de Cultura , Fermentação , Inulina/isolamento & purificação , Lactobacillus/crescimento & desenvolvimento , Lactobacillus/metabolismo , Polimerização , Prebióticos
8.
Drug Dev Ind Pharm ; 41(7): 1066-72, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24918173

RESUMO

Throughout the period of evaluation and selection in drug development, the assessment of the permeability potential of a compound to achieve an efficient refinement of the molecular structure has been widely appraised by the transport of substances across cell monolayers. This study aims to develop in vitro assays through Caco-2 cells in order to analyze the permeability of 5-nitro-heterocyclic compounds analogues to nifuroxazide with antimicrobial activity, especially showing promising activity against multidrug-resistant Staphylococcus aureus (MRSA). Caco-2 cell monolayers cultivated for 21 days in Transwell® plates were used for the in vitro permeability assays. The quantification of the nifuroxazide derivatives in the basolateral chambers was performed by a validated high performance liquid chromatography with UV (HPLC-UV) method. Apparent permeability values (Papp) show that these compounds can be considered as new drug candidates with the potential to present high absorption in vivo, according to the classifications of Yee and Biganzoli. The thiophenic derivatives showed permeability values higher than the furanic ones, being AminoTIO the compound with the greatest potential for the development of a new drug against MRSA, since it showed the best cytotoxicity, permeability and solubility ratio among all the derivatives.


Assuntos
Anti-Infecciosos/administração & dosagem , Hidroxibenzoatos/administração & dosagem , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Nitrofuranos/administração & dosagem , Anti-Infecciosos/farmacocinética , Anti-Infecciosos/farmacologia , Células CACO-2 , Cromatografia Líquida de Alta Pressão , Humanos , Hidroxibenzoatos/farmacocinética , Hidroxibenzoatos/farmacologia , Nitrofuranos/farmacocinética , Nitrofuranos/farmacologia , Permeabilidade , Solubilidade , Espectrofotometria Ultravioleta
9.
ScientificWorldJournal ; 2012: 495970, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22623901

RESUMO

While many natural and synthetic compounds exhibit auxin-like activity in bioassays, indole-3-acetic acid (IAA) is recognized as the key auxin in most plants. IAA has been implicated in almost all aspects of plant growth and development and a large array of bacteria have been reported to enhance plant growth. Cells of Klebsiella oxytoca isolated from the rhizosphere of Aspidosperma polyneuron and immobilized by adsorption on different inorganic matrices were used for IAA production. The matrices were prepared by the sol-gel method and the silica-titanium was the most suitable matrix for effective immobilization. In operational stability assays, IAA production was maintained after four cycles of production, obtaining 42.80 ± 2.03 µg mL(-1) of IAA in the third cycle, which corresponds to a 54% increase in production in relation to the first cycle, whereas free cells began losing activity after the first cycle. After 90 days of storage at 4°C the immobilized cells showed the slight reduction of IAA production without significant loss of activity.


Assuntos
Ácidos Indolacéticos/metabolismo , Klebsiella oxytoca/metabolismo , Adsorção , Biomassa , Células Imobilizadas/metabolismo , Raízes de Plantas/microbiologia , Rizosfera , Dióxido de Silício , Titânio
10.
Mar Pollut Bull ; 64(5): 1074-8, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22482868

RESUMO

The epi-benthic dinoflagellate Ostreopsis cf. ovata Fukuyo has an increasingly global distribution. In Brazil there are reports of O. cf. ovata along the coast from 8°S to 27°S latitude and blooms have been registered on the Rio de Janeiro coastline. In the current study, an O. cf. ovata bloom is reported at Saint Paul's Rocks (0°55'10″N; 29°20'33″W), between the southern and northern hemispheres. The Archipelago is not inhabited and not subjected to eutrophication, due to isolation, and sustains a number of endemic species. Therefore, blooms of O. cf. ovata may potentially cause demise to trophic chains by affecting marine invertebrates and vertebrates.


Assuntos
Dinoflagellida/crescimento & desenvolvimento , Eutrofização , Poluição da Água/análise , Oceano Atlântico , Monitoramento Ambiental
11.
Toxicol In Vitro ; 26(3): 535-40, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22285235

RESUMO

It is important to determine the toxicity of compounds and co-solvents that are used in cell monolayer permeability studies to increase confidence in the results obtained from these in vitro experiments. This study was designed to evaluate the cytotoxicity of new nifuroxazide derivatives with potential activity against Methicillin-resistant Staphylococcus aureus (MRSA) in Caco-2 cells to select analogues for further in vitro permeability analyses. In this study, nitrofurantoin and nifuroxazide, in addition to 6 furanic and 6 thiophenic nifuroxazide derivatives were tested at 2, 4, 6, 8 and 10 µg/mL. In vitro cytotoxicity assays were performed according to the MTT (methyl tetrazolium) assay protocol described in ISO 10993-5. The viability of treated Caco-2 cells was greater than 83% for all tested nitrofurantoin concentrations, while those treated with nifuroxazide at 2, 4 and 6 µg/mL had viabilities greater than 70%. Treatment with the nifuroxazide analogues resulted in viability values greater than 70% at 2 and 4 µg/mL with the exception of the thiophenic methyl-substituted derivative, which resulted in cell viabilities below 70% at all tested concentrations. Caco-2 cells demonstrated reasonable viability for all nifuroxazide derivatives, except the thiophenic methyl-substituted compound. The former were selected for further permeability studies using Caco-2 cells.


Assuntos
Anti-Infecciosos/toxicidade , Hidroxibenzoatos/toxicidade , Nitrofuranos/toxicidade , Nitrofurantoína/toxicidade , Anti-Infecciosos/administração & dosagem , Anti-Infecciosos/química , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Hidroxibenzoatos/administração & dosagem , Hidroxibenzoatos/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Nitrofuranos/administração & dosagem , Nitrofuranos/química , Nitrofurantoína/administração & dosagem
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