Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Food Chem ; 345: 128853, 2021 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-33340900

RESUMO

Fifty potato genotypes from twenty-four different countries of origin, four different flesh colours (yellow, purple, red and marble) and different cultivation types (Andean accessions, landraces, breeder lines and cultivated varieties) were studied in terms of their nutritional and physicochemical characteristics. In general, cultivated varieties and breeder lines showed the highest similarity (slight differences only in some particular fatty acids distributions: C10:0, C12:0 and C22:0) concerning the physicochemical parameters assayed in this work, independently of the geographical origin or tuber flesh colour of these genotypes. Nonetheless, some of the studied landraces and Andean accessions proved to be similar enough to be considered as genotypes with good potential for commercial cultivation. These results can contribute to the supply of new potato genotypes into sustainable farming systems, supporting the protection of potato biodiversity, particularly Andean accessions, landraces and coloured genotypes (red or purple flesh) which are not widely cultivated so far.


Assuntos
Biodiversidade , Fenômenos Químicos , Genótipo , Valor Nutritivo , Solanum tuberosum/química , Análise Discriminante , Tubérculos/química , Solanum tuberosum/classificação
2.
Int J Pharm ; 598: 120375, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33581271

RESUMO

Metronidazole is the drug of choice in the treatment of bacterial vaginosis, but the oral therapy can induce several collateral effects. Aim of this work was the development of a vaginal multiparticulate system, loaded with metronidazole, able to improve its residence time allowing a complete drug release. Several kinds of MS were prepared using chitosan dissolved in different organic acids or alginate coated with chitosan. FTIR and DSC analyses were performed to study the interactions between the drug and the polymers, while MS morphology was investigated with optical and electron microscopy. All the formulations were characterized in terms of drug entrapment efficiency, mucoadhesion, swelling capacity and drug release behavior, demonstrating the best results for alginate MS coated with chitosan. The formulations evidenced a complete and rapid release of drug, compared with the commercial form: Zidoval®.The best formulations assayed for antibacterial activity confirmed the suitability of this new formulation for the vaginal treatment of local diseases.


Assuntos
Quitosana , Administração Intravaginal , Alginatos , Feminino , Humanos , Metronidazol , Microesferas
3.
Food Chem ; 310: 125980, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31838371

RESUMO

Cyanidin-3-O-glucoside (C3G) is principal anthocyanin in Chinese bayberry wine and its degradation is main problem with respect to wine color. Effect of five organic acids existing in bayberry wine on C3G oxidation mediated by iron was investigated in model wine. Fe(II) oxidation was found to follow a decreasing order in oxalate > citrate > tartrate > malate model wine whereas it hardly occurred in succinate model wine. The C3G oxidation mediated by iron followed an increasing order in citrate > oxalate > succinate > malate > tartrate model wine. More degradation products were observed in succinate, malate and tartrate model wine than in citrate and oxalate model wine. C3G degradation mediated by Fe(III) was faster than that mediated by Fe(II) in oxalate, succinate, malate, and tartrate model wine, but not in citrate model wine. C3G oxidation mediated by iron is probably not main mechanism of anthocyanin degradation in bayberry wine.


Assuntos
Antocianinas/metabolismo , Ácidos Dicarboxílicos/química , Glucosídeos/metabolismo , Ferro/metabolismo , Myrica , Vinho , Antocianinas/química , Cor , Ácidos Dicarboxílicos/metabolismo , Glucosídeos/química , Ferro/química , Malatos/química , Myrica/química , Myrica/metabolismo , Oxirredução , Ácido Succínico/química , Ácido Succínico/metabolismo , Tartaratos/química , Vinho/análise
4.
Carbohydr Polym ; 229: 115476, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31826488

RESUMO

The objective of present study is to explore whether polysaccharide could be a crystal growth inhibitor in poorly soluble antitumor drug Ibrutinib (IBR) formulation. In this work, small molecular ligands (amino or organic acids) in co-amorphous system (CAS) were preliminarily screened. A polysaccharide, microcrystalline cellulose (MCC) was selected to stabilize amorphous drug and enhance pharmacokinetic properties. Fourier-transform infrared, Raman, and X-ray photoelectron spectroscopy confirmed the ionic interaction of the ternary IBR formulation. Moreover, the biosafety of the ternary formulation was the same as that of IBR while the in vitro performance advantage of the ternary formulation was converted into higher bioavailability in vivo experiments. Overall, MCC as an effective crystal growth inhibitor in the novel ternary IBR formulation is a promising approach to improve the dissolution rate of crystalline drugs and the stability of amorphous drugs, as well as providing a theoretical basis for clinical applications.


Assuntos
Celulose/química , Pirazóis/química , Pirimidinas/química , Adenina/análogos & derivados , Animais , Disponibilidade Biológica , Linhagem Celular Tumoral , Fenômenos Químicos , Cristalização , Composição de Medicamentos , Humanos , Masculino , Piperidinas , Pirazóis/farmacocinética , Pirazóis/farmacologia , Pirimidinas/farmacocinética , Pirimidinas/farmacologia , Ratos
5.
Food Chem ; 276: 790-796, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30409664

RESUMO

Rapid deterioration of postharvest Agaricus bisporus is a serious problem. Measures to improve the shelf-life are of great importance. Therefore, we used a nanocomposite-based packaging material (Nano-PM) containing nano-TiO2, nano-SiO2, nano-Ag and attapulgite to study its effect on microstructure and energy metabolism of A. bisporus. Nano-PM reduced the oxidation of lipids and proteins by activating antioxidant enzyme activities and inhibiting the accumulation of ROS, thereby maintained high level of energy status. Meanwhile, ATP content and energy charge of A. bisporus in Nano-PM increased through the energy metabolism system. This was attributed to the lower respiration rate and higher mitochondrial respiratory enzyme activities. These results indicated that Nano-PM could maintain the dense and intact microstructure of A. bisporus thus improve its shelf-life.


Assuntos
Agaricus/metabolismo , Agaricus/ultraestrutura , Embalagem de Alimentos/métodos , Nanocompostos , Antioxidantes/química , Antioxidantes/metabolismo , Metabolismo Energético , Enzimas/química , Enzimas/metabolismo , Embalagem de Alimentos/instrumentação , Conservação de Alimentos/métodos , Proteínas Fúngicas/metabolismo , Mitocôndrias/metabolismo , Nanocompostos/química , Oxirredução , Dióxido de Silício/química , Prata/química , Titânio
6.
Carbohydr Polym ; 181: 292-299, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29253975

RESUMO

1,2,3,4-Butanetetracarboxylic acid (BTCA) can efficiently esterify cellulose with pyrophosphoric acid (PPA) as a catalyst to remove protons of reaction intermediates. However, valence and relative concentration ratio (RCR) of catalyst anions correlating to pH of finishing bath played a critical role in the reactions. Results here indicated that wrinkle recovery angle, tensile strength retention and ester absorbance of fabrics treated at pH of 2.8 showed higher values. It was a competing reaction for BTCA molecules to esterify or depolymerize cellulose. Importantly, divalent PPA anions were more efficient than monovalent ones in catalyzing the esterification between anhydrides and cellulose, which was confirmed by FTIR results and two-dimensional correlation spectroscopy analyses and by the RCRs of PPA anions and their changing rates versus pH. Furthermore, the higher catalytic efficiency of divalent anions was proved by the selected model catalysts. Meaningfully, the fabrics treated at pH≤3.2 presented good durability.

7.
Food Chem ; 266: 161-169, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30381171

RESUMO

Untargeted metabolomics unraveled the effects of varying substrates (soybean, wheat, and rice) and inocula (Aspergillus oryzae and Bacillus amyloliquefaciens) on metabolite compositions of koji, a starter ingredient in various Asian fermented foods. Multivariate analyses of the hyphenated mass spectrometry datasets for different koji extracts highlighted 61 significantly discriminant primary metabolites (sugars and sugar alcohols, organic acids, amino acids, fatty acids, nucleosides, phenolic acids, and vitamins) according to varying substrates and inocula combinations. However, 59 significantly discriminant secondary metabolites were evident for koji-types with varying substrates only, viz., soybean (flavonoids, soyasaponins, and lysophospholipids), wheat (flavones and lysophospholipids), and rice (flavonoids, fatty acids derivatives, and lysophospholipids). Independently, the substrates influenced primary metabolite compositions in koji (soybean > wheat, rice). The inocula choice of A. oryzae engendered higher carbohydrates, organic acids, and lipid derivative levels commensurate with high α-amylase and ß-glucosidase activities, while B. amyloliquefaciens affected higher amino acids levels, in respective koji types.


Assuntos
Aspergillus oryzae/metabolismo , Bacillus amyloliquefaciens/metabolismo , Glycine max/metabolismo , Metabolômica , Oryza/metabolismo , Triticum/metabolismo , Aminoácidos/análise , Carboidratos/análise , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Cromatografia Gasosa-Espectrometria de Massas , Concentração de Íons de Hidrogênio , Hidroxibenzoatos/análise , Análise de Componente Principal , Vitaminas/análise , alfa-Amilases/metabolismo , beta-Glucosidase/metabolismo
8.
Food Chem ; 254: 272-280, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29548454

RESUMO

Grape, orange, peach and passion fruit nectars were formulated and adulterated by dilution with syrup, apple and cashew juices at 10 levels for each adulterant. Attenuated total reflectance Fourier transform mid infrared (ATR-FTIR) spectra were obtained. Partial least squares (PLS) multivariate calibration models allied to different variable selection methods, such as interval partial least squares (iPLS), ordered predictors selection (OPS) and genetic algorithm (GA), were used to quantify the main fruits. PLS improved by iPLS-OPS variable selection showed the highest predictive capacity to quantify the main fruit contents. The selected variables in the final models varied from 72 to 100; the root mean square errors of prediction were estimated from 0.5 to 2.6%; the correlation coefficients of prediction ranged from 0.948 to 0.990; and, the mean relative errors of prediction varied from 3.0 to 6.7%. All of the developed models were validated.


Assuntos
Contaminação de Alimentos/análise , Néctar de Plantas/análise , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Brasil , Calibragem , Citrus sinensis , Frutas/química , Análise dos Mínimos Quadrados , Néctar de Plantas/química , Prunus persica , Espectrofotometria Infravermelho , Espectroscopia de Infravermelho com Transformada de Fourier/estatística & dados numéricos , Vitis
9.
Food Chem ; 224: 92-96, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28159298

RESUMO

Vitamin C is usually quantified by titrimetric or chromatographic methods. However, these methods have limitations: food color interferes with the titrimetric method and the chromatographic method is costly. The aim of this study was to compare a spectrophotometric method, based on reduction of cupric ions in the presence of cuproine complex, with a titrimetric method, based on reduction of 2,6-dicholorophenolindophenol. Linearity, precision, accuracy, and limits of detection (LOD) and quantification (LOQ) were evaluated using a standard vitamin C solution. Both methods were also applied for AA quantification in industrialized orange and pineapple juices. The methods were precise and accurate when applied to the standard solution. The spectrophotometric method was more sensitive, with lower values for LOD (0.002mgmL-1) and LOQ (0.010mgmL-1), and more accurate with error less than 5% while results from the titrimetric method were affected by the juice color, which generated errors in excess of 15%.


Assuntos
Ananas , Ácido Ascórbico/análise , Técnicas de Química Analítica/métodos , Citrus sinensis , Sucos de Frutas e Vegetais/análise , Técnicas de Química Analítica/normas , Limite de Detecção , Espectrofotometria/métodos , Espectrofotometria/normas , Titulometria/métodos , Titulometria/normas
10.
Food Chem ; 231: 258-266, 2017 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-28450005

RESUMO

A time-resolved non-targeted metabolomic study towards evaluating the effects of three rice substrate types viz., white rice (WR), giant embryo rice (GER), and brown rice (BR), on Koji fermentation was performed. Notwithstanding the relatively higher proportions of metabolites in unfermented BR (BR 0>WR 0, GER 0), the relative levels of metabolic repertoire in BR Koji were marginally enhanced during 36h fermentation except those for phenolic acids, fatty acids, and vitamins. The WR Koji showed higher levels of lysophospholipids (LysoPC's) and protease-released amino acids (WR 36>GER 36>BR 36). The higher ß-glucosidase activity in GER Koji effected the increased levels of sugars and flavonoid aglycons complementing its higher antioxidant activity (GER Koji>BR Koji∼WR Koji). The present study holistically underpins the dynamic metabolomes and enzymatic states during rice Koji fermentation with varying substrate types. The present study finds applications in optimization of commercial Koji production.


Assuntos
Fermentação , Metaboloma , Oryza , Flavonoides , Oxirredução
11.
Food Chem ; 201: 80-6, 2016 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-26868551

RESUMO

This study aimed to evaluate the effects of different cooking methods on the content of important nutrients and volatiles in the fruit of Chinese chestnut. The nutritional compounds, including starch, water-soluble protein, free amino acids, reducing sugar, sucrose, organic acids and total flavonoids, of boiled, roasted and fried chestnuts were significantly (P<0.05) lower than those of fresh chestnuts after cooking, while the amylose, fat, crude protein and total polyphenol content varied slightly (P>0.05). L-Aspartic acid, L-glutamic acid and L-arginine were found to be the main reduced free amino acids in cooked chestnuts. The main aromatic compositions in fresh chestnuts were aldehydes and esters, while ketones, furfural and furan were formed in cooked chestnuts due to the Maillard reaction and degradation of saccharides, amino acids and lipids. Principle component analysis demonstrated that roasting and frying had a similar effect on the nutritional composition of chestnuts, which differed from that of the boiling process.


Assuntos
Culinária/métodos , Eleocharis/química , Frutas/química , Valor Nutritivo , Flavonoides/análise , Reação de Maillard , Compostos Orgânicos Voláteis
12.
Food Chem ; 201: 168-76, 2016 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-26868562

RESUMO

The effect of storage at two temperatures (5±1 and 25±1 °C and 60-70±5% RH for both temperatures) on marketability and quality features of dry bulbs of local landrace "Vatikiotiko", "Sivan F1", "Red Cross F1" and "Creamgold" was examined. During storage measurements for fresh and dry weight of bulbs, tunic and flesh color, bulb firmness, nutritional value and mineral composition were taken at regular intervals. Storage concluded when either bulbs lost marketable quality or sprouting occurred. "Vatikiotiko" onion can be stored for at least 7months at 25±1 °C, whereas at 5±1 °C storage could be prolonged without significant marketability and quality loss. The fact that "Vatikiotiko" landrace can be considered a "storage" onion has to be capitalized in order to increase total production and yield, since storage could cover the market needs that arise throughout the year.


Assuntos
Valor Nutritivo , Cebolas/química , Armazenamento de Alimentos , Grécia , Minerais/análise , Temperatura
13.
Food Chem ; 185: 200-4, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25952858

RESUMO

The contributions of free hydrogen ions, undissociated hydrogen ions in protonated acid species, and anionic acid species to sour taste were studied through sensory experiments. According to tasting results, it can be inferred that the basic substance producing a sour taste is the hydrogen ion, including free hydrogen ions and undissociated hydrogen ions. The intensity of a sour taste is determined by the total concentration of free hydrogen ions and undissociated hydrogen ions. The anionic acid species (without hydrogen ions) does not produce a sour taste but can intensify or weaken the intensity of a sour taste. It seems that hydroxyl or conjugated groups in anionic acid species can intensify the sour taste produced by hydrogen ions. The following strategy to reduce the sensory sourness is advanced: not only reduce free hydrogen ions, namely elevate pH value, but also reduce the undissociated hydrogen ions contained in protonated acid species.


Assuntos
Cerveja/análise , Ácido Acético/química , Prótons , Percepção Gustatória
14.
Food Chem ; 179: 318-24, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-25722171

RESUMO

Graphene oxide (GO) is a pH-dependent amphiphile. In this paper, it was found that carbon nanotubes (CNTs) can be highly dispersed in graphene oxide "water" with the aid of prototype ionic liquid of 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6]). The introduction of [BMIM][PF6] not only can minimize the defects of poor electrical conductivity of GO, but also can improve the dispersibility of CNT in water. Hence, a new composite of CNT/GO-[BMIM][PF6] with high dispersibility and strong conductivity was presented for the first time and employed in the sensitive determination of Amaranth in soft drinks. The detection limit achieved (0.1 nM) is much lower than the guideline values in soft drinks. The ease of preparation, low background current, high sensitivity and stability can create novel avenues and applications for fabricating robust sensors for determination of other azo dyes in foods.


Assuntos
Bebidas/análise , Grafite/metabolismo , Líquidos Iônicos/metabolismo , Água/química , Corante Amaranto , Análise de Alimentos , Nanotubos de Carbono
15.
Food Chem ; 182: 156-63, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25842322

RESUMO

"Vatikiotiko" is an onion local landrace from Greece with special quality features, such as strong and pungent taste and storability. In this study, we tried for the first time to describe this landrace and record its morphological traits and nutritional value in comparison with commercially cultivated genotypes ("Creamgold", "Red Cross F1" and "Sivan F1"). Nutritional value of "Vatikiotiko" was higher than commercial genotypes, whereas total sugars, fructose and glucose content were lower in "Vatikiotiko" and "Creamgold" onions. Fatty acids composed mostly from polyunsaturated fatty acids (linoleic and α-linolenic acid), whereas for "Vatikiotiko" saturated and monounsaturated fatty acids were detected in equal amounts (29.79% and 30.60%, respectively). "Vatikiotiko" and "Creamgold" had low antioxidant activity (DPPH radical scavenging activity), especially when comparing with "Sivan F1" and "Red Cross F1", whereas no flavonoids were detected in "Vatikiotiko". The overview of "Vatikiotiko" landrace supported its special character regarding its nutritional value (sugar content, mineral composition and fatty acids profile) and the necessity to revalorize and protect its traditional culture. The potential of introducing it as Protected Designation of Origin (PDO) or Protected Geographical Indication (PGI) product has also been discussed.


Assuntos
Antioxidantes/análise , Flavonoides/análise , Valor Nutritivo , Cebolas/química , Ácido alfa-Linolênico/análise , Análise de Alimentos , Genótipo , Grécia , Minerais/análise , Cebolas/genética , Cebolas/crescimento & desenvolvimento
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa