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1.
Food Chem ; 447: 139023, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38507949

RESUMO

This study presents a method employing gas chromatography coupled with mass spectrometry and headspace solid-phase microextraction (HS-SPME-GC-MS), supplemented with chemometrics (Soft independent modelling of class analogies - SIMCA), to analyze volatile organic compound (VOCs) profiles in suspect whiskey samples. Furthermore, a sensory analysis of aroma and color was conducted with a panel of 52 non-trained volunteers to evaluate their ability to discriminate and preference for counterfeit whiskeys. The HS-SPME-GC-MS method successfully distinguished 41 seized samples from authentic beverages. Interestingly, sensory analysis revealed that panelists could differentiate between counterfeit and authentic samples with a reference standard but did not consistently show a preference for aroma. In some cases, there was even a preference for the color of counterfeit whiskeys. The findings suggest that sensorial tests alone may not effectively distinguish counterfeit from authentic whiskeys, especially for non-expert consumers, highlighting the need for analytical instrumentation methods in fraud detection.


Assuntos
Odorantes , Compostos Orgânicos Voláteis , Humanos , Odorantes/análise , Compostos Orgânicos Voláteis/análise , Bebidas Alcoólicas/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectrometria de Massas , Microextração em Fase Sólida/métodos
2.
Food Chem ; 397: 133857, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-35944334

RESUMO

The objectives of this study were to extract bioactive compounds from carrot by-products and evaluate their chemical stability after encapsulation in liposomes (L) coated either with chitosan (Ch) or using sodium tripolyphosphate for chitosan complexation (TPP-Ch). The main compounds quantified in this study were carotenoids and total phenolic compounds, which reached encapsulation efficiencies higher than 75%. The TPP-Ch charged with carrot extract showed greater particle size (90.5 nm) and zeta potential (+22 mV) than vesicles without coating (68.0 nm and -2 mV, respectively), indicating that liposomes were successfully coated with chitosan. Regarding results of the carotenoid's encapsulated stability, TPP-Ch particles were more efficient preventing their degradation in all the experimental conditions studied (40 and 70 °C). It is significant that loaded TPP-Ch particles demonstrated similar results for the stability of carotenoid-rich extracts in ethanol, which would therefore be suitable for application in food industry or any aqueous matrices.


Assuntos
Quitosana , Daucus carota , Carotenoides , Quitosana/química , Daucus carota/química , Lipossomos/química , Tamanho da Partícula
3.
Int J Mol Sci ; 23(13)2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35806282

RESUMO

Inspired by the composition and confined environment provided by collagen fibrils during bone formation, this study aimed to compare two different strategies to synthesize bioactive hybrid membranes and to assess the role the organic matrix plays as physical confinement during mineral phase deposition. The hybrid membranes were prepared by (1) incorporating calcium phosphate in a biopolymeric membrane for in situ hydroxyapatite (HAp) precipitation in the interstices of the biopolymeric membrane as a confined environment (Methodology 1) or (2) adding synthetic HAp nanoparticles (SHAp) to the freshly prepared biopolymeric membrane (Methodology 2). The biopolymeric membranes were based on hydrolyzed collagen (HC) and chitosan (Cht) or κ-carrageenan (κ-carr). The hybrid membranes presented homogeneous and continuous dispersion of the mineral particles embedded in the biopolymeric membrane interstices and enhanced mechanical properties. The importance of the confined spaces in biomineralization was confirmed by controlled biomimetic HAp precipitation via Methodology 1. HAp precipitation after immersion in simulated body fluid attested that the hybrid membranes were bioactive. Hybrid membranes containing Cht were not toxic to the osteoblasts. Hybrid membranes added with silver nanoparticles (AgNPs) displayed antibacterial action against different clinically important pathogenic microorganisms. Overall, these results open simple and promising pathways to develop a new generation of bioactive hybrid membranes with controllable degradation rates and antimicrobial properties.


Assuntos
Quitosana , Nanopartículas Metálicas , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Quitosana/metabolismo , Quitosana/farmacologia , Colágeno/metabolismo , Durapatita/metabolismo , Osteoblastos/metabolismo , Prata/metabolismo , Prata/farmacologia
4.
Int J Biol Macromol ; 202: 508-519, 2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35007637

RESUMO

In this study, we have isolated starch from turmeric dye extraction residue by steeping in acid medium (AS), steeping in water (WS), or steeping in alkaline medium (KS) and assessed the filmogenic capacity of the resulting starches. We have also characterized the chemical composition, morphology, swelling power, solubility, crystallinity, and active properties of the AS, WS, and KS starches and investigated the mechanical, functional, antioxidant, and antimicrobial properties of the corresponding films. The AS and KS starches showed lower apparent amylose content and higher purity, relative crystallinity, swelling power, and solubility than the WS starch. All the starches retained phenolic compounds and curcuminoids; their phenolic and curcuminoid contents were higher than the contents in the residue, especially in the case of the AS starch, which yielded films with the best antioxidant and antimicrobial activities. The AS and KS starches yielded films that were more resistant at break, less soluble in water, and less hydrophilic than the film obtained from the WS starch. Thus, submitting turmeric dye extraction residue to AS in ascorbic acid yielded a starch that resulted in films with good mechanical properties and better antioxidant and antimicrobial properties, to ensure safe and prolonged food shelf life.


Assuntos
Curcuma , Amido , Amilose/química , Solubilidade , Amido/química , Água
5.
Int J Biol Macromol ; 183: 614-626, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-33933543

RESUMO

The potential use of nopal cladode flour (NC) as reinforcing/bioactive agent in cassava starch-based films was evaluated and compared with the use of propolis extract or lignin, which are commonly used for these purposes. Cassava starch-based films containing untreated NC (S-NC), NC treated at pH 12 (S-NC12), aqueous propolis extract at two different concentrations (SP1 or SP2), or lignin (S-L) were produced by the casting technique; glycerol was used as plasticizer. NC12 and NC affected the mechanical properties of the cassava starch-based film similarly as compared to propolis extract and lignin. Moreover, NC and NC12 had different performance as reinforcing and antioxidant agent in cassava starch-based film. Thus, S-NC12 film was more elongable (28.5 ± 6.5%), more hydrophobic (contact angle: 70.8° ± 0.1), less permeable to water vapor (0.8 ± 0.0 × 10-10 g·m-1·s-1·Pa-1) and had better antioxidant activity by ABTS•+ (44.70 ± 0.3 µM Trolox·g-1 of film) than the S-NC film. SEM and TGA analysis of films showed that NC12 was better incorporated into the cassava starch matrix than NC, lignin and propolis extract. Overall, nopal cladode flour has potential use in the production of active biodegradable packaging for the food preservation with high oxidation rate.


Assuntos
Antioxidantes/farmacologia , Filmes Comestíveis , Aditivos Alimentares/farmacologia , Embalagem de Alimentos , Conservação de Alimentos , Lignina/farmacologia , Manihot , Opuntia , Própole/farmacologia , Amido/farmacologia , Antioxidantes/isolamento & purificação , Aditivos Alimentares/isolamento & purificação , Interações Hidrofóbicas e Hidrofílicas , Manihot/química , Opuntia/química , Amido/isolamento & purificação
6.
Eur J Pharm Biopharm ; 165: 127-148, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33992754

RESUMO

Nanotechnology has been widely applied to develop drug delivery systems to improve therapeutic performance. The effectiveness of these systems is intrinsically related to their physicochemical properties, so their biological responses are highly susceptible to factors such as the type and quantity of each material that is employed in their synthesis and to the method that is used to produce them. In this context, quality-oriented manufacturing of nanoparticles has been an important strategy to understand and to optimize the factors involved in their production. For this purpose, Design of Experiment (DoE) tools have been applied to obtain enough knowledge about the process and hence achieve high-quality products. This review aims to set up the bases to implement DoE as a strategy to improve the manufacture of nanocarriers and to discuss the main factors involved in the production of the most common nanocarriers employed in the pharmaceutical field.


Assuntos
Portadores de Fármacos/química , Composição de Medicamentos/métodos , Nanopartículas/química , Projetos de Pesquisa , Química Farmacêutica , Nanomedicina/métodos
7.
Carbohydr Polym ; 123: 406-15, 2015 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-25843874

RESUMO

In this study, variations in the delignification and bleaching stages, acid hydrolysis and high-pressure homogenization, led to the development of 12 different treatments applied for obtaining nanofibers using fibrous residues arising from the starch extraction process from the achira rhizomes. The treatments were evaluated based on some properties and characteristics of nanofibers such as: morphology and size (by means of transmission electron microscopy), surface charge (by means of zeta potential measurements), crystallinity index (by means of X-ray diffraction analysis) and functional groups (by means of infrared spectroscopy). In general, the nanofibers showed particle diameters between 13.8 and 37.2nm, length between 832.8 and 2223.8nm and high crystallinity index (57.5% and 69.8%) compared with achira fibrous residue (17.3%). The results evidenced that fibrous residue from achira rhizomes can be used as a source of biodegradable materials of commercial interest.


Assuntos
Nanofibras/química , Amido/química , Hidrólise , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Pressão , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/metabolismo , Ácidos Sulfúricos/química , Difração de Raios X
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