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1.
Trop Anim Health Prod ; 55(3): 142, 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37016138

RESUMO

Rumen-protected fat (RPF) was produced in the 1st experimental stage through melt-emulsification technique using buriti oil (BO) as core, at concentrations of 10% (BO10), 20% (BO20), and 30% (BO30) (w/w), and carnauba wax (CW) as encapsulant material. After obtention and characterization, protected fat microspheres were tested in a 2nd experimental stage on the sheep' diet using six castrated 2-year-old male Santa Ines with initial weight 48.9 ± 5.23 kg, fistulated in rumen and distributed in a double Latin square design with 3 treatments × 3 periods, to evaluate rumen pH, temperature, protozoal count, and blood parameters. There was no difference (P > 0.05) among RPF microspheres for microencapsulation yield. However, microencapsulation efficiency increased (P < 0.05) with BO addition ranging from 36 to 61.3% for BO10 and BO30, respectively. The inclusion of BO10 in the sheep's diet did not affect the ruminal dry matter degradability (DMD) of BO over time (P > 0.05); however, BO20 and BO30 had higher (P < 0.05) DMD values than BO10. No significant differences were observed among RPF for rumen pH and temperature (P > 0.05). There was an increase (P < 0.05) in the protozoal population in the rumen environment due to the microencapsulated BO30 inclusion. There was also increase (P < 0.05) in serum albumin, cholesterol, aspartate aminotransferase (ALT), and gamma-glutamyltransferase (GGT), and a reduction (P < 0.05) in serum triglycerides of the sheep when RPF microspheres increased in the diet. Melt-emulsification proved to be a good technique for microencapsulation of buriti oil into the carnauba wax matrix. RPF from buriti oil protected into carnauba wax is recommended for sheep diet because it increases energy density, without adverse effects on the protozoal populations and blood serum metabolites from the bypass effect in the rumen.


Assuntos
Dieta , Rúmen , Animais , Masculino , Ração Animal/análise , Dieta/veterinária , Suplementos Nutricionais , Digestão , Fermentação , Rúmen/metabolismo , Ovinos
2.
J. Health Biol. Sci. (Online) ; 10(1): 1-10, 01/jan./2022. tab, ilus, graf
Artigo em Inglês | LILACS | ID: biblio-1364028

RESUMO

Objectives: Evaluation of phenolic compounds and antioxidant activities of aqueous extracts of C. longa, P. nigrum and C. cyminum. In addition to proposing a quantum-mechanical model to evaluate the antioxidant activity. Methods: The aqueous extracts were prepared using roots of the Curcuma longa L., seeds of the Piper nigrum L. and seeds of Cuminum cyminum. The extracts were subjected to tests to detect and quantify phenolic compounds and to assess their antioxidant capacity by different methods. Furthermore, to investigate the electronic nature of the antioxidant activity of the main compounds present in these extracts, frontier molecular orbitals (FMOs) were obtained by the DFT/B3LYP/6-31G(d,p) level of theory. Results: After statistical analysis of the results, a greater number of phenolic compounds and better antioxidant activity was identified in the aqueous extracts of cumin (C. cyminum) in all three assays performed, when compared to the other extracts tested. The theoretical model based on the Pietro method is in agreement with the experimental results. Conclusion: This study has an innovative proposal with the trivial antioxidant activity combined with theoretical quantum-mechanical calculations that can serve to reduce costs and time and to predict the antioxidant activity of subsequent studies.


Objetivos: avaliar os compostos fenólicos e atividades antioxidantes dos extratos aquosos de C. longa, P. nigrum e C. cyminum bem como propor um modelo quanto-mecânico para avaliar a atividade antioxidante. Métodos: os extratos aquosos foram preparados por meio da utilização de raízes de Curcuma longa L., sementes de Piper nigrum L. e sementes de Cuminum cyminum. Os extratos foram submetidos a ensaios para detectar e quantificar compostos fenólicos e atividade antioxidante por diferentes métodos. Além disso, com objetivo de investigar a natureza eletrônica da atividade antioxidante dos principais compostos presentes nesses extratos, orbitais moleculares de fronteira (OMFs) foram obtidos pelo nível de teoria DFT/B3LYP/6-31G(d,p). Resultados: após as análises estatísticas dos resultados, a maior quantidade de compostos fenólicos com maior atividade antioxidante foi identificada no extrato aquoso do cominho (C. cyminum) em todos os ensaios realizados, quando comparados com os outros extratos testados. O modelo teórico baseado no método de Pietro está concordante com os resultados experimentais. Conclusão: este estudo possui uma proposta inovadora com a atividade antioxidante trivial combinada com cálculos quanto-mecânicos que podem servir para reduzir custos e tempo para predizer a atividade antioxidante de estudos futuros.


Assuntos
Piper nigrum , Curcuma , Compostos Fitoquímicos , Áreas de Fronteira , Compostos Fenólicos , Teoria da Densidade Funcional , Antioxidantes
3.
Molecules ; 24(18)2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31505873

RESUMO

In this work we report the synthesis of new hybrid nanomaterials in the core/shell/shell morphology, consisting of a magnetite core (Fe3O4) and two consecutive layers of oleic acid (OA) and phthalocyanine molecules, the latter derived from cashew nut shell liquid (CNSL). The synthesis of Fe3O4 nanoparticle was performed via co-precipitation procedure, followed by the nanoparticle coating with OA by hydrothermal method. The phthalocyanines anchorage on the Fe3O4/OA core/shell nanomaterial was performed by facile and effective sonication method. The as obtained Fe3O4/OA/phthalocyanine hybrids were investigated by Fourier transform infrared spectroscopy, X-ray diffraction, UV-visible spectroscopy, transmission electron microscopy (TEM), thermogravimetric analysis and magnetic measurements. TEM showed round-shaped nanomaterials with sizes in the range of 12-15 nm. Nanomaterials presented saturation magnetization (Ms) in the 1-16 emu/g and superparamagnetic behavior. Furthermore, it was observed that the thermal stability of the samples was directly affected by the insertion of different transition metals in the ring cavity of the phthalocyanine molecule.


Assuntos
Anacardium/química , Indóis/química , Nanopartículas/química , Nanoestruturas/química , Compostos Férricos/química , Óxido Ferroso-Férrico/química , Isoindóis , Microscopia Eletrônica de Transmissão , Nanopartículas/ultraestrutura , Nanoestruturas/ultraestrutura , Nozes/química , Dióxido de Silício/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
4.
J Sci Food Agric ; 99(3): 1078-1087, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30022472

RESUMO

BACKGROUND: The high ureolytic activity of rumen microbiota is a concern when urea is used in ruminant feed, because it leads to fast urea conversion, resulting in possible intoxication and lower nitrogen utilization. This study intended to microencapsulate urea using carnauba wax to obtain slow-release systems in the rumen. The experiment was conducted in a randomized block design, arranged in a 3 × 2 factorial, with the urea encapsulated with carnauba wax in ratios of 1 : 2; 1 : 3, and 1 : 4 (UME 2; UME 3, and UME 4) and two particles sizes (small, PS ; and large, PL ). RESULTS: All formulations showed excellent properties, including inhibition of urea hygroscopicity. The formulation UME 2 exhibited the greatest yield (91.6%) and microencapsulation efficiency (99.6%) values, whereas the formulation UME 4 presented the greatest thermal stability (259.5 °C) and lowest moisture content (1.81%). The UME 2 formulation presented a slower release than the other UME formulations studied. CONCLUSION: The production of urea microspheres using carnauba wax was successful for all microencapsulated systems developed, evidencing the promising potential for use in ruminant animal diets. The UME 2 formulation with large particles is the most recommended because it permitted greater resistance to microbial attack, allowing a slower release of urea into the rumen, reducing the risk of intoxication or ruminal alkalosis. © 2018 Society of Chemical Industry.


Assuntos
Composição de Medicamentos/veterinária , Ureia/administração & dosagem , Ceras/química , Ração Animal/análise , Animais , Dieta/veterinária , Composição de Medicamentos/métodos , Masculino , Rúmen/efeitos dos fármacos , Rúmen/metabolismo , Carneiro Doméstico , Ureia/química , Ureia/farmacocinética
5.
Int J Biol Macromol ; 101: 1-8, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28315762

RESUMO

Pectin and cellulose nanocrystals (CNCs) isolated from banana peels were used to prepare films. The effects of a reinforcing phase (CNCs) and a crosslinker (citric acid, CA) on properties of pectin films were studied. Glycerol-plasticized films were prepared by casting, with different CNC contents (0-10wt%), with or without CA. Overall tensile properties were improved by intermediate CNC contents (around 5wt%). The water resistance and water vapor barrier properties were also enhanced by CNC. Evidences were found from Fourier Transform Infrared (FTIR) spectra supporting the occurrence of crosslinking by CA. Additionally, the tensile strength, water resistance and barrier to water vapor were improved by the presence of CA. The 13C ssNMR spectra indicated that both CA and CNC promoted stiffening of the polymer chains.


Assuntos
Musa/química , Nanocompostos/química , Pectinas/química , Celulose/química , Ácido Cítrico/química , Nanopartículas/química
6.
Food Chem ; 198: 113-8, 2016 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-26769512

RESUMO

A central composite design was used to determine effects of pH (2.0-4.5), extraction temperature (70-90 °C) and time (120-240 min) on the yield, degree of methoxylation (DM) and galacturonic acid content (GA) of pectins extracted from banana peels with citric acid. Changes in composition during the main steps of pectin extraction were followed by Fourier transform infrared (FTIR) spectroscopy. FTIR was also used to determine DM and GA of pectins. Harsh temperature and pH conditions enhanced the extraction yield, but decreased DM. GA presented a maximum value at 83 °C, 190 min, and pH 2.7. The yield of galacturonic acid (YGA), which took into account both the extraction yield and the pectin purity, was improved by higher temperature and lower pH values. The optimum extraction conditions, defined as those resulting in a maximum YGA while keeping DM at a minimum of 51%, were: 87 °C, 160 min, pH 2.0.


Assuntos
Ácido Cítrico/química , Musa/química , Pectinas/química , Polissacarídeos
7.
Int J Mol Sci ; 14(9): 18269-83, 2013 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-24013376

RESUMO

This paper describes the investigation and development of a novel magnetic drug delivery nanosystem (labeled as MO-20) for cancer therapy. The drug employed was oncocalyxone A (onco A), which was isolated from Auxemma oncocalyx, an endemic Brazilian plant. It has a series of pharmacological properties: antioxidant, cytotoxic, analgesic, anti-inflammatory, antitumor and antiplatelet. Onco A was associated with magnetite nanoparticles in order to obtain magnetic properties. The components of MO-20 were characterized by XRD, FTIR, TGA, TEM and Magnetization curves. The MO-20 presented a size of about 30 nm and globular morphology. In addition, drug releasing experiments were performed, where it was observed the presence of the anomalous transport. The results found in this work showed the potential of onco A for future applications of the MO-20 as a new magnetic drug release nanosystem for cancer treatment.


Assuntos
Antraquinonas/química , Antineoplásicos/química , Boraginaceae/química , Magnetismo , Nanopartículas de Magnetita/química , Sistemas de Liberação de Medicamentos/métodos , Microscopia Eletrônica de Transmissão , Extratos Vegetais/química , Espectroscopia de Infravermelho com Transformada de Fourier
8.
Talanta ; 106: 249-54, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23598124

RESUMO

A glutathione-S-transferase (GST) based biosensor was developed to quantify the thiocarbamate herbicide molinate in environmental water. The biosensor construction was based on GST immobilization onto a glassy carbon electrode via aminosilane-glutaraldehyde covalent attachment. The principle supporting the use of this biosensor consists of the GST inhibition process promoted by molinate. Differential pulse voltammetry was used to obtain a calibration curve for molinate concentration, ranging from 0.19 to 7.9 mg L(-1) and presenting a detection limit of 0.064 mg L(-1). The developed biosensor is stable, and reusable during 15 days. The GST-based biosensor was successfully applied to quantify molinate in rice paddy field floodwater samples. The results achieved with the developed biosensor were in accordance with those obtained by high performance liquid chromatography. The proposed device is suitable for screening environmental water analysis and, since no sample preparation is required, it can be used in situ and in real-time measurements.


Assuntos
Azepinas/análise , Enzimas Imobilizadas/química , Glutationa Transferase/química , Herbicidas/análise , Tiocarbamatos/análise , Poluentes Químicos da Água/análise , Água/química , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/normas , Calibragem , Carbono , Reagentes de Ligações Cruzadas/química , Técnicas Eletroquímicas , Eletrodos , Reutilização de Equipamento , Glutationa/química , Humanos
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