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1.
Food Chem ; 441: 138338, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38194794

RESUMO

This study focuses on the characterisation and incorporation of Moringa oleifera leaf powder (MOP) from Luanda (Angola) and its extract (MOE) in fortified chocolate mousse. Dark green (DG) leaves presented superior nutritional values compared to other leaves. DG contained a higher concentration of mineral salts (10 ± 1 mg/100 g of dry leaves), phenolic compounds (267 ± 4 mg GAE/g), vitamins (1.9 ± 0.2 mg/g of dry extract) and strong antioxidant capacity (IC50, 115 ± 8 µg/mL). Therefore, DG leaves were used to fortify the chocolate mousse. The leaves were prepared in three samples: control, 2 % MOP (w/w) and 2 % MOE (v/v). Textural and rheological analysis of chocolate mousse samples revealed a pseudoplastic profile for all samples, with decreased texture attributes and viscosity due to the incorporation. The sensory evaluation demonstrated that MOP and MOE samples presented 93 % and 88 % resemblance to the original product regarding general acceptance, respectively.


Assuntos
Chocolate , Moringa oleifera , Extratos Vegetais , Pós , Folhas de Planta , Vitaminas
2.
Int J Pharm ; 634: 122671, 2023 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-36736965

RESUMO

Hydrogels are extensively used in the biomedical field, as drug delivery systems, wound dressings, contact lenses or as scaffolds for tissue engineering. Due to their polymeric nature and the presence of high amounts of water in their structure, hydrogels generally present high sensitivity to terminal sterilization. The establishment of an efficient sterilization protocol that does not compromise the functional properties of the hydrogels is one of the challenges faced by researchers when developing a hydrogel for a specific application. Yet, until very recently this aspect was largely ignored in the literature. The present paper reviews the state of literature concerning hydrogels sterilization, compiling the main findings. Conventional terminal sterilization methods (heat sterilization, radiation sterilization, and gas sterilization) as well as emerging sterilization techniques (ozone, supercritical carbon dioxide) are covered. Considerations about aseptic processing are also included. Additionally, and as a framework, hydrogels' polymeric materials, types of networks, and main biomedical applications are summarily described.


Assuntos
Lentes de Contato , Hidrogéis , Hidrogéis/química , Esterilização/métodos , Polímeros/química , Água , Engenharia Tecidual
3.
Front Plant Sci ; 13: 867803, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35656011

RESUMO

The scarce availability of efficient and eco-friendly nematicides to control root-knot nematodes (RKN), Meloidogyne spp., has encouraged research toward the development of bionematicides. Naphthoquinones, juglone (JUG) and 1,4-naphthoquinone (1,4-NTQ), are being explored as alternatives to synthetic nematicides to control RKN. This study expands the knowledge on the effects of these natural compounds toward M. luci life cycle (mortality, hatching, penetration, reproduction). M. luci second-stage juveniles (J2)/eggs were exposed to each compound (250, 150, 100, 50, and 20 ppm) to monitor nematode mortality and hatching during 72 h and 15 days, respectively. Tomato seedlings were then inoculated with 200 J2, which had been exposed to JUG/1,4-NTQ for 3 days. The number of nematodes inside the roots was determined at 3 days after inoculation, and the final population density was assessed at 45 days after inoculation. Moreover, the potential mode of action of JUG/1,4-NTQ was investigated for the first time on RKN, through the assessment of reactive oxygen species (ROS) generation, acetylcholinesterase (AChE) in vitro inhibitory activity and expression analysis of ache and glutathione-S-transferase (gst) genes. 1,4-NTQ was the most active compound, causing ≥50% J2 mortality at 250 ppm, within 24 h. At 20 and 50 ppm, hatching was reduced by ≈50% for both compounds. JUG showed a greater effect on M. luci penetration and reproduction, decreasing infection by ≈80% (50 ppm) on tomato plants. However, 1,4-NTQ-induced generation of ROS and nematode vacuolization was observed. Our study confirms that JUG/1,4-NTQ are promising nematicidal compounds, and new knowledge on their physiological impacts on Meloidogyne was provided to open new avenues for the development of innovative sustainable nematicides.

4.
Int J Pharm ; 556: 117-124, 2019 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-30528632

RESUMO

Aerosol antibiotics are an interesting alternative to oral or intravenous therapy in Cystic Fibrosis lung infections. Levofloxacin (LVX) inhaled solution is already an effective option. In this study, the aim was the development of LVX-loaded PLGA microspheres (MS) for pulmonary administration as a dry powder. MS were prepared, for the first time, by a modified double emulsion solvent evaporation method with premix membrane homogenization. Aqueous phases were saturated with LVX and a fatty acid (lauric acid) was added to avoid the drug escaping from the organic phase. MS were characterized in terms of size, drug content, morphology and in vitro release properties. X-ray diffraction, Fourier-transform infrared spectroscopy, differential and gravimetric thermal analysis, and cytotoxicity analyses were performed. Results showed this new method increased the drug loading while maintaining an adequate (∼5 µm) particle size and controlled release. Compared to a solution for inhalation, these properties combined with the dry-powder nature of these MS will improve patient compliance. The incorporation of lauric acid was not advantageous because the particle size was higher and no improvements concerning the sustained release occurred. LVX was molecularly dispersed in the matrix, or it was in amorphous state, as confirmed by the physico-chemical analyses. Calu-3 cell viability assays demonstrated no cytotoxicity for these MS, making them a promising system for LVX pulmonary delivery.


Assuntos
Antibacterianos/administração & dosagem , Levofloxacino/administração & dosagem , Microesferas , Antibacterianos/química , Antibacterianos/toxicidade , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Química Farmacêutica/métodos , Preparações de Ação Retardada , Portadores de Fármacos/química , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Inaladores de Pó Seco , Humanos , Ácidos Láuricos/química , Levofloxacino/química , Levofloxacino/toxicidade , Tamanho da Partícula , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Solventes/química
5.
Nat Prod Res ; 32(6): 732-738, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28627294

RESUMO

The present work is focused on the characterisation of the polyphenolic content of an Oxalis pes-caprae L. leaf extract and on the evaluation of its bioactivity with particular interest on its vascular activity and antioxidant potential. The polyphenolic content was characterised by HPLC-DAD and LC-MS/MS. The vascular activity was evaluated according to the influence on the serotonergic and adrenergic systems of the human internal mammary artery (HIMA). Antioxidant and neuroprotective studies were also conducted. Several luteolin and apigenin derivatives were identified as main constituents of the extract, which did not present any contractile effect nor had any effect on the serotonergic system of HIMA. However, it showed antagonistic effect on the adrenergic system, inhibiting the contraction to noradrenaline (reduction of 58.44% of maximum contraction). The extract showed antioxidant activity and standardised luteolin and apigenin derivatives showed neuroprotective potential, particularly homoorientin.


Assuntos
Antioxidantes/farmacologia , Fármacos Neuroprotetores/farmacologia , Oxalidaceae/química , Folhas de Planta/química , Polifenóis/farmacologia , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Antioxidantes/química , Apigenina/análise , Cromatografia Líquida de Alta Pressão , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Luteolina/análise , Luteolina/farmacologia , Artéria Torácica Interna/efeitos dos fármacos , Camundongos , Fármacos Neuroprotetores/química , Norepinefrina/farmacologia , Extratos Vegetais/análise , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Polifenóis/análise , Polifenóis/química , Ratos , Espectrometria de Massas em Tandem
6.
Eur J Pharm Sci ; 93: 184-91, 2016 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-27531420

RESUMO

A comparative pharmacokinetic study was conducted in rats after intratracheal aerosolization of levofloxacin, as a solution, as immediate-release chitosan microspheres or as sustained-release PLGA microspheres. A pharmacokinetic model was constructed to model levofloxacin concentrations both in plasma and in the lung epithelial lining fluid (ELF). The plasma and ELF experimental concentration profiles versus time were similar for the intravenous and intratracheal levofloxacin solutions and for the intratracheal levofloxacin-loaded chitosan microsphere dry powder, indicating that levofloxacin diffused almost instantaneously through the broncho-alveolar barrier and that the chitosan microspheres released levofloxacin very rapidly, as anticipated from in vitro release studies. The bioavailability for the intratracheal levofloxacin solution and intratracheal chitosan microspheres was estimated to be 98% and 71%, respectively, both with a direct release into the ELF compartment. The ELF-to-unbound plasma AUC ratios were slightly above 2 and may result from an efflux transport. For the intratracheal PLGA microspheres, a high ELF-to-unbound plasma AUC concentration ratio (311) was observed and high levofloxacin concentrations were maintained in ELF for at least 72h in consistency with the in vitro release studies. The bioavailability was 92%, with 19% of the dose released immediately (burst release) into the ELF and 73% released slowly into the ELF from a depot compartment, i.e. the PLGA microspheres, according to a Weibull model. These results highlight the benefit of using sustained-release microspheres administered as aerosols to provide and to maintain high pulmonary concentrations of an antibiotic characterized with a high permeability profile through the broncho-alveolar barrier. The sustained-release microsphere dry powder aerosol may therefore provide advantages over solutions or pure drug dry powders for inhalation in terms of treatment efficiency, ease of use and frequency of administration.


Assuntos
Antibacterianos , Quitosana/química , Ácido Láctico/química , Levofloxacino , Ácido Poliglicólico/química , Administração por Inalação , Aerossóis , Animais , Antibacterianos/administração & dosagem , Antibacterianos/sangue , Antibacterianos/química , Antibacterianos/farmacocinética , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Levofloxacino/administração & dosagem , Levofloxacino/sangue , Levofloxacino/química , Levofloxacino/farmacocinética , Masculino , Microesferas , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ratos Sprague-Dawley
7.
Eur J Pharm Biopharm ; 96: 65-75, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26192459

RESUMO

The aim of this work was the development of innovative levofloxacin-loaded swellable microspheres (MS) for the dry aerosol therapy of pulmonary chronicPseudomonas aeruginosainfections in Cystic Fibrosis patients. In a first step, a factorial design was applied to optimize formulations of chitosan-based MS with glutaraldehyde as crosslinker. After optimization, other crosslinkers (genipin, glutaric acid and glyceraldehyde) were tested. Analyses of MS included aerodynamic and swelling properties, morphology, drug loading, thermal and chemical characteristics,in vitroantibacterial activity and drug release studies. The prepared MS presented a drug content ranging from 39.8% to 50.8% of levofloxacin in an amorphous or dispersed state, antibacterial activity and fast release profiles. The highest degree of swelling was obtained for MS crosslinked with glutaric acid and genipin. These formulations also presented satisfactory aerodynamic properties, making them a promising alternative, in dry-powder inhalers, to levofloxacin solution for inhalation.


Assuntos
Antibacterianos/administração & dosagem , Quitosana/química , Reagentes de Ligações Cruzadas/química , Portadores de Fármacos/química , Levofloxacino/administração & dosagem , Terapia Respiratória/métodos , Tecnologia Farmacêutica/métodos , Antibacterianos/química , Antibacterianos/uso terapêutico , Fibrose Cística/tratamento farmacológico , Fibrose Cística/microbiologia , Liberação Controlada de Fármacos , Humanos , Levofloxacino/química , Levofloxacino/uso terapêutico , Microesferas , Tamanho da Partícula , Difração de Pó , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/isolamento & purificação , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície
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