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1.
Biomolecules ; 10(1)2020 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-31963518

RESUMO

Flaxseed oil cake extract (residual from cold-press oil production and rich in proteins and polysaccharides) was evaluated as a potential substrate for the preparation of spray-dried powders with emulsifying activity. Three variants of powders were obtained using different spray-drying process inlet temperatures: 160 °C, 180 °C, and 200 °C. The influence of temperature on physicochemical features (water holding capacity, oil binding capacity, water activity, solubility, color, chemical composition, antioxidant activity, and surface morphology) of the powders was estimated. Additionally, the emulsifying activity of the powders and the stability of oil-in-water emulsions prepared with their various content (0.5%, 1%, and 3%) were determined. Results showed that inlet temperature had significant influence on all physicochemical and functional properties of the powders. Increased inlet temperature decreased solubility and antioxidant activity but increased water-holding capacity, oil-binding capacity, and emulsifying activity. The emulsions prepared with the powder obtained at 200 °C showed the highest stability. SEM images showed the production of relatively spherical particles which were folded or wrinkled with a lot of dentures. This study could open a promising pathway for producing natural and plant-based spray-dried powders for food applications as emulsion stabilizers.


Assuntos
Emulsões/química , Aditivos Alimentares/química , Óleo de Semente do Linho/química , Antioxidantes/química , Linho/química , Pós , Solubilidade , Secagem por Atomização , Temperatura , Água/química
2.
Foods ; 8(11)2019 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-31684151

RESUMO

Flaxseed oil cake (FOC) was evaluated as a potential substrate for the production of a novel kefir-like fermented beverage. Three variants containing 5%, 10%, and 15% (w/w) of FOC were inoculated with kefir grains and incubated at 25 °C for 24 h. After processing, beverages were stored in refrigerated conditions (6 °C) for 21 days. Changes in microbial population, pH, acidity, levels of proteins, polyphenolics, flavonoids, ascorbic acid, and reducing sugars were estimated. Additionally, viscosity, firmness, color, and antioxidant properties were determined. Results showed that lactic acid bacteria as well as yeast were capable of growing well in the FOC without any supplementation. During refrigerated storage, the viability of the microorganisms were over the recommended minimum level for kefir products. As a result of fermentation, the beverages showed excellent antioxidant activity. Because of the functional characteristics conferred to the FOC beverages, the use of kefir grains showed adequate potential for the industrial application. Therefore, this beverages could be used as a new, non-dairy vehicle for beneficial microflora consumption, especially by vegans and lactose-intolerant consumers.

3.
Molecules ; 24(17)2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31461850

RESUMO

Because of the bacterial drug resistance development, it is reasonable to investigate chemical compounds capable of preventing the spread of resistance to mupirocin (MUP), commonly used in staphylococcal eradication. The objective of the study was to verify the influence of essential oil compounds (EOCs) on the antibacterial activity of MUP against mupirocin-susceptible (MupS) and induced low-level mupirocin-resistant (MupRL) methicillin-resistant Staphylococcus aureus (MRSA) strains. The following parameters were examined: MRSAMupS and MRSAMupRL susceptibility to EOCs (1,8-cineole, eugenol, carvacrol, linalool, (-)-menthone, linalyl acetate, and trans-anethole), the bacterial cell size distribution, and chemical composition by the use of Fourier Transform Infrared Spectroscopy (FTIR) and Raman spectroscopies. The MRSAMupS and MRSAMupRL strains were susceptible to all tested EOCs. 1,8-cineole and (-)-menthone showed synergistic activity against MRSAMupS in combination with mupirocin, whereas 1,8-cineole exhibited synergistic activity against MRSAMupRL as well. In-depth analysis showed that both MRSAMupS and MRSAMupRL displayed similar distributions of the bacterial cell size. The FTIR and Raman spectra of the MRSAMupS and MRSAMupRL strains showed differences in some regions. New bands in the MRSAMupRL Raman spectrum were observed. It was concluded that the use of 1,8-cineole in combination with mupirocin can increase the mupirocin activity against the MRSAMupS and MRSAMupRL strains.


Assuntos
Antibacterianos/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Óleos Voláteis/farmacologia , Antibacterianos/isolamento & purificação , Sinergismo Farmacológico , Eucaliptol/isolamento & purificação , Eucaliptol/farmacologia , Humanos , Mentol/isolamento & purificação , Mentol/farmacologia , Viabilidade Microbiana/efeitos dos fármacos , Mupirocina/farmacologia , Óleos Voláteis/isolamento & purificação , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
4.
Carbohydr Polym ; 181: 317-326, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29253978

RESUMO

The purpose of this study was to compare the effects of increasing concentrations of ascorbate ions (AIs, 0-100mM) in the form of ascorbic acid (AA) and sodium ascorbate (SA) on the properties of edible oxidized potato starch films. The browning reactions were faster in the SA-added films than in those of AA-added. In, turn, AA recrystallized faster than its sodium salt. The highest concentration of SA increased the water vapor permeability of the films. The mechanical strength and stiffness of the films gradually decreased with the increase of AI content. Fourier-transform infrared spectroscopy spectra suggested that addition of SA provoked a more intensive structural changes in the films than AA. X-ray diffraction showed that 25 and 50mM AI-added films exhibited higher crystanility than the control. The films with AA and SA did not differ in terms of dissolving behavior, ability to release AI, and consequently, antioxidant activity.


Assuntos
Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Fenômenos Químicos , Solanum tuberosum/química , Amido/química , Cristalização , Umidade , Concentração de Íons de Hidrogênio , Ferro/química , Fenômenos Ópticos , Oxirredução , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Vapor , Difração de Raios X
5.
Molecules ; 22(9)2017 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-28926973

RESUMO

The influence of accelerated UV-A and Q-SUN irradiation on the antimicrobial properties of coatings containing ZnO nanoparticles was investigated using a polyethylene (PE) film covering. The results of the study showed that Methyl Hydroxypropyl Celluloses (MHPC) coatings did not influence the growth of S. aureus, B. cereus, E. coli, P. aeruginosa or C. albicans cells. MHPC coatings containing ZnO nanoparticles inhibited the growth of bacterial strains and reduced the number of C. albicans strains. Accelerated Q-SUN and UV-A irradiation had no influence on the antimicrobial effect of nano ZnO coatings against S. aureus, B. cereus and E. coli. Q-SUN irradiation decreased the activity of MHPC coatings containing nanoparticles against P. aeruginosa and C. albicans. An FT-IR analysis clearly showed that ZnO nanoparticles shielded the MHPC coating during Q-SUN irradiation.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Nanopartículas Metálicas/química , Óxido de Zinco/química , Antibacterianos/efeitos da radiação , Antifúngicos/efeitos da radiação , Bacillus cereus/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Excipientes/química , Luz , Nanopartículas Metálicas/efeitos da radiação , Microscopia Eletrônica de Varredura/métodos , Tamanho da Partícula , Pseudomonas aeruginosa/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Staphylococcus aureus/efeitos dos fármacos , Propriedades de Superfície , Óxido de Zinco/efeitos da radiação
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