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1.
J Agric Food Chem ; 67(37): 10352-10360, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31503479

RESUMO

The potential for apple peels to mitigate the deleterious effects of a high-fat diet in mice was investigated here. Mice were fed a high-fat diet supplemented with apple powders from three apple varieties or a commercial apple polyphenol. Polyphenols were characterized using colorimetric assays and high-performance liquid chromatography. Mice were tested for standard metabolic parameters. There was a dose response to dietary apple peels, with the higher intake leading to reduced weight gain and adipose tissue mass relative to the lower intake, but none of the treatments were statistically different from the control. The gene expression of liver enzyme stearoyl-CoA desaturase (Scd-1) was correlated with adipose weight, and liver enzyme cytochrome P51 (Cyp51) was downregulated by the apple diets. The feces from a subset of mice were analyzed for polyphenols and for bacteria taxa by next-generation sequencing. The results revealed that the makeup of the fecal microbiota was related to the metabolism of dietary polyphenols.


Assuntos
Biflavonoides/análise , Catequina/análise , Fezes/química , Frutas/metabolismo , Microbioma Gastrointestinal , Malus/metabolismo , Obesidade/dietoterapia , Proantocianidinas/análise , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Biflavonoides/metabolismo , Catequina/metabolismo , Dieta Hiperlipídica/efeitos adversos , Frutas/química , Humanos , Masculino , Malus/química , Camundongos , Obesidade/genética , Obesidade/metabolismo , Obesidade/microbiologia , Polifenóis/análise , Polifenóis/metabolismo , Proantocianidinas/metabolismo , Estearoil-CoA Dessaturase/genética , Estearoil-CoA Dessaturase/metabolismo , Esterol 14-Desmetilase/genética , Esterol 14-Desmetilase/metabolismo
2.
Food Chem ; 299: 125092, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31280001

RESUMO

The health-promoting functions of fruit phenolic compounds are mainly attributed to their metabolites. The organic cultivation of fruits is becoming increasingly popular. Thus, this study evaluates whether the differences in red Grenache grapes derived from organic culture conditions influence the bioavailability and metabolism of phenolic compounds in rats. Organic and nonorganic (conventional) red Grenache grapes (OG and CG, respectively) were characterized and administered to Wistar rats (65 mg gallic acid equivalents/kg bw). Serum was recollected at different time points, and the phenolic metabolites were quantified by HPLC-ESI-MS/MS. The results showed that organic cultivation increased the oligomeric proanthocyanidin and anthocyanidin contents and decreased the content of free flavanols and dietary fiber. The serum profile of OG-administered rats showed higher metabolite concentrations at 2 h and reduced metabolite concentration at 24 h compared with the CG-administered rats. Thus, this particular serum kinetic behavior might influence the bioactivity of their phenolic compounds.


Assuntos
Agricultura Orgânica , Fenóis/farmacocinética , Vitis/química , Animais , Antocianinas/análise , Antocianinas/farmacocinética , Disponibilidade Biológica , Cromatografia Líquida de Alta Pressão , Fibras na Dieta/análise , Análise de Alimentos/métodos , Frutas/química , Masculino , Fenóis/análise , Polifenóis/análise , Polifenóis/farmacocinética , Proantocianidinas/análise , Proantocianidinas/farmacocinética , Ratos Wistar , Espectrometria de Massas em Tandem
3.
Food Chem ; 298: 125068, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260977

RESUMO

In this work, 18 gluten-free flours (prepared from cereals, pseudocereals and legumes), differing in pigmentation, were screened for their phenolic profiles, cooked and, then, subjected to digestion and large intestinal fermentation in vitro. A combined targeted/untargeted metabolomic approach was used to elucidate the microbial biotransformation processes of polyphenols following digestion. This preliminary work demonstrated an increase in 3,5-dihydroxybenzoic acid (on average from 0.67 up to 1.30 µmol/g dry matter) throughout large intestinal fermentation of pseudocereals (esp. quinoa), due to their high alkylresorcinol contents. Isoflavones were converted into equol- or O-desmethylangolensin- derivatives, whereas anthocyanins were degraded into lower-molecular-weight phenolics (i.e., protocatechuic aldehyde and 4-hydroxybenzoic acid, with the latter exhibiting the highest increase over time). A decreasing trend was observed for antioxidant activities (i.e., FRAP and ORAC values) moving from digested to faecal fermented samples. These findings highlight that gluten-free flours are able to deliver bioaccessible polyphenols to the colon.


Assuntos
Farinha/análise , Intestino Grosso/microbiologia , Polifenóis/metabolismo , Animais , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Técnicas de Cultura Celular por Lotes , Cromatografia Líquida de Alta Pressão , Culinária , Fezes/microbiologia , Polifenóis/análise , Polifenóis/química , Espectrometria de Massas por Ionização por Electrospray , Suínos
4.
Food Chem ; 298: 125046, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260981

RESUMO

We established a novel Dianhong black tea grades discriminant analytic technique based on a fluorescence image along with carbon quantum dots (CDs) as fluorescent probes. Different grades of Dianhong black tea contain different various amounts of tea polyphenols. Tea polyphenols can quench the fluorescent intensity of CDs, resulting in different fluorescent peaks; Dianhong black tea grades can then be discriminated through the use of principal component analysis and Bayesian analysis. Compared with the additional data processing required in other methods, the advantage of our method is that the fluorescence curve can be used directly, and it achieves satisfactory results. We firstly used CDs combined with chemometrics to identify eight grades of Dianhong black tea, and we also provide a new method that improves the identification rate using nanotechnology to avoid performing complex data processing.


Assuntos
Camellia sinensis/química , Corantes Fluorescentes/química , Teorema de Bayes , Camellia sinensis/metabolismo , Análise Discriminante , Polifenóis/análise , Análise de Componente Principal , Pontos Quânticos/química , Espectrometria de Fluorescência
5.
Chem Biodivers ; 16(8): e1900205, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31294527

RESUMO

The importance of phenolic compounds for responding to various environmental conditions has been widely emphasized. However, the role of interactions between polyphenols and ecological factors, especially C, N, and P stoichiometry was little studied. Here, 15 sites across five provinces of Pinus bungeana in temperate regions of China were studied. The results showed that the higher values of total phenolic contents (TPC) of leaf and litter were distributed among the north distribution area of P. bungeana, lower values were in the south, whereas soil TPC were contrary to leaf and litter TPC. The stepwise regression, path analysis and decision index of path analysis for leaf TPC and ecological factors showed that altitude had the most direct impact on leaf TPC. Moreover, the principal determinants of leaf, litter and soil TPC were soil C/P ratios, longitude, and soil N/P ratios, respectively. In addition, the leaf, litter and soil TPC of P. bungeana were limited by soil C/N ratios, mean annual temperature, and soil P, respectively. Overall, our study provided evidence that ecological factors affected strongly the leaf, litter and soil TPC of P. bungeana.


Assuntos
Pinus/química , Polifenóis/química , Solo/química , Carbono/química , China , Colorimetria , Ecossistema , Nitrogênio/química , Fósforo/química , Pinus/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Polifenóis/análise , Temperatura Ambiente
6.
Zhongguo Zhong Yao Za Zhi ; 44(12): 2467-2471, 2019 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-31359712

RESUMO

Three different origins of Anoectochilus roburghii were used as experimental materials to study the effect of three different substrate( peat soil-river sand-peanut shell) radio on survival rate,plant height,stem diameter,plant fresh weight,root number,the longest root length,root diameter,and the contents of polysaccharide,flavonoids,and polyphenol. The results showed that when the substrate ratio was 4 ∶2 ∶2,the survival rate of A. roburghii from different origins was the highest,and the plant height,stem diameter,plant fresh weight,the longest root length and root diameter were also the largest. The cultivation substrate had no significant effect on the polysaccharide content of A. roxburghii and A. formosanus. When the substrate ratio was 4 ∶ 2 ∶ 2,the polysaccharide content of A.chapaensis was significantly lower than that of the other two combinations. When the substrate ratio was 4 ∶2 ∶1,the flavonoid content of A. formosanus was higher than that of the other two combinations. When the substrate ratio was 4 ∶2 ∶2,A. formosanus and A. chapaensis had higher polyphenol content.


Assuntos
Flavonoides/análise , Orchidaceae/química , Orchidaceae/crescimento & desenvolvimento , Polifenóis/análise , Polissacarídeos/análise
7.
J Sci Food Agric ; 99(13): 5834-5841, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31206711

RESUMO

BACKGROUND: Many studies have described cocoa polyphenols as being bioactive compounds with a potential positive effect on human health. Although dark chocolate is a most powerful source of antioxidants, their content is lower in milk chocolate; conversely, in white chocolate the fat-free cocoa solids are omitted. The aim of this study was to increase polyphenol content and antioxidant capacity of white chocolate by adding encapsulated green tea extract (GTE) in amounts of 60, 80 and 100 g kg-1 . RESULTS: GTE influenced the particle size parameters, increasing the volume weighted mean from 15.43 µm in white chocolate to 19.34 µm in chocolate with 100 g kg-1 GTE. At the same time, the viscosity of enriched chocolate also increased owing to the addition of new solid particles. The surface color of enriched chocolates changed in accordance with the amount of encapsulate, where all enriched chocolates had a slightly lighter color after 12 months of storage. Total polyphenol content (mg gallic acid equivalents (GAE) kg-1 ) increased from 0.41 in white chocolate to 2.73 in chocolate enriched with maximal GTE. This amount of GTE increased antioxidant capacity (mmol Trolox equivalents kg-1 ) from 1.22 in white chocolate to 16.12. After 12 months of storage, degradation of polyphenols was found to be a maximum of 37.27%, while antioxidant capacity decreased up to 44.14%. CONCLUSION: In addition to the impact on chocolate viscosity, GTE added value through the polyphenol content and sensorial profile of the new product with an unusual green tea flavor and a shelf life of at least 12 months. © 2019 Society of Chemical Industry.


Assuntos
Cacau/química , Camellia sinensis/química , Chocolate/análise , Aditivos Alimentares/análise , Extratos Vegetais/análise , Antioxidantes/análise , Manipulação de Alimentos , Humanos , Polifenóis/análise , Paladar , Viscosidade
8.
Food Chem ; 295: 493-498, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174786

RESUMO

Fining treatment with polyvinylpolypyrrolidone (PVPP) is often used during winemaking of rosé wines. It can modulate the intensity and hue of their pink color and prevent some organoleptic degradations. In this paper, the effect of PVPP treatments on rosé wine during fermentation was investigated by measuring color, polyphenol content and thiol aromas. As expected, colorimetry results showed a decrease in color, indicating some adsorption of anthocyanins and other pigments. This was confirmed by UPLC-ESI-MS/MS analyses. Specific adsorption of certain families of polyphenols was evidenced. Flavonols, flavanols and anthocyanins, especially coumaroylated anthocyanins were preferentially adsorbed by PVPP. The thiol content (3-sulfanylhexyl acetate (3SHA) and 3-sulfanylhexan-1-ol (3SH)) was usually higher after PVPP treatments, in a dose dependent manner. A possible explanation is that the partial adsorption of some polyphenols at an early stage of fermentation would later limit the amount of quinone compounds able to trap thiol aromas.


Assuntos
Odorantes/análise , Polifenóis/metabolismo , Povidona/análogos & derivados , Compostos de Sulfidrila/análise , Vinho , Antocianinas/análise , Cor , Colorimetria , Fermentação , Flavonóis/análise , Hexanóis/análise , Polifenóis/análise , Povidona/farmacologia , Espectrometria de Massas em Tandem , Vinho/análise
9.
Food Chem ; 295: 165-171, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174746

RESUMO

Deep eutectic solvents (DES) and aqueous glycerol were proposed as green alternatives to conventional solvents for the extraction of polyphenols from grapefruit peels. In order to increase the extraction kinetics and yields of polyphenols, high voltage electrical discharges (HVED) were used as a pre-treatment technology (energy varied between 7.27 and 218 kJ/kg). Results showed that the HVED energy input can be reduced, when the subsequent solid-liquid extraction was performed in 20% (w/v) aqueous glycerol or in DES (lactic acid: glucose) instead of water. The addition of glycerol has reduced the energy of the pre-treatment by 6 times. The same diffusivity of polyphenols (4 × 10-11 m2/s) was obtained in water from HVED pre-treated peels at 218 kJ/kg and in aqueous glycerol from pre-treated peels at 36 kJ/kg. The solubility of naringin, the main flavonoid compound of grapefruit peels in the solvents, was investigated through a theoretical modelling of its Hansen solubility parameters.


Assuntos
Citrus paradisi/química , Glicerol/química , Polifenóis/isolamento & purificação , Solventes/química , Cromatografia Líquida de Alta Pressão , Citrus paradisi/metabolismo , Eletricidade , Flavanonas/química , Flavonoides/química , Glucose/química , Ácido Láctico/química , Extração Líquido-Líquido , Polifenóis/análise , Solubilidade , Água/química
10.
Food Chem ; 295: 289-299, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174761

RESUMO

A method combining solid-liquid extraction based on ethanolic aqueous solution, cLC-DAD and chemometrics, was performed to extract and quantify polyphenols from citrus peels. LC-MS/MS was also employed for chemical profiling. The effect of extraction variables on the recovery was examined by experimental factorial design. Data were evaluated using multifactorial-ANOVA, response surface analysis and Principal Component Analysis. trans-Ferulic and p-coumaric antioxidants were found in lower quantities (<1.4 mg·g-1) in all peel extracts. Narangin flavonoid was also identified in all samples, while rutin flavonol was determined in the concentration range of 3.3-4.7 mg·g-1. The most abundant polyphenol in the extracts obtained from all evaluated citrus samples was the flavanone hesperidin (280-673 mg·g-1). Furthermore, peel extracts were evaluated in terms of total polyphenol and flavonoid content, total antioxidant activity and DPPH free radical scavenging. The obtained results suggested that evaluated citrus peel by-products could be reused as a source of polyphenols and transformed into value-added products.


Assuntos
Citrus/química , Polifenóis/análise , Polifenóis/isolamento & purificação , Resíduos/análise , Análise de Variância , Antioxidantes/análise , Antioxidantes/isolamento & purificação , Cromatografia Líquida , Flavonoides/análise , Flavonoides/isolamento & purificação , Hesperidina/análise , Hesperidina/isolamento & purificação , Extratos Vegetais/análise , Extratos Vegetais/química , Análise de Componente Principal , Espectrometria de Massas em Tandem
11.
Food Chem ; 295: 341-349, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174767

RESUMO

The inclusion of edible wild plants in human diet has been receiving an increasing attention, as they represent an easily accessible source of nutrients, vitamins and antioxidants. In this work, the leaves of Umbelicus rupestris (Salisb.) Dandy, an edible species for which only scarce data is available in literature, were thoroughly evaluated for its nutritional profile, chemical characterization and bioactive properties. Being considered a succulent plant, the leaves revealed a very high content of moisture, with several beneficial compounds, including omega-3 polyunsaturated fatty acids, tocopherols and different polyphenols. A total of twelve flavonoids, three phenolic acids and one phenylpropanoid glucoside were identified in the decoction and/or hydroethanolic extracts, with most of them being described for the first time in this plant. Both extracts showed antioxidant activity and potential to inhibit some of the assayed bacteria, while not presenting cytotoxic effects on a non-tumour primary cell culture.


Assuntos
Magnoliopsida/química , Valor Nutritivo , Plantas Comestíveis/química , Antioxidantes/análise , Flavonoides/análise , Hidroxibenzoatos/análise , Extratos Vegetais/análise , Extratos Vegetais/química , Folhas de Planta/química , Polifenóis/análise , Portugal , Tocoferóis/análise
12.
Plant Foods Hum Nutr ; 74(3): 443-445, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31183803

RESUMO

The antioxidant activity of ginger and turmeric powders derived from freeze-dried rhizomes and peels as well as commercial spices has been evaluated by two spectrophotometric assays based on electron transfer such as DPPH and FRAP. The phenolic characterization has been also carried out by detecting total polyphenols through Folin-Ciocalteu method and HPLC analysing 6-gingerol and curcumin. Ginger and turmeric peels showed greater antioxidant activity than commercial powders because of their higher phenolic yields. Hence, ginger and turmeric peels can be considered a rich source of phytochemicals which contribute to the antioxidant effects of these agro-food wastes.


Assuntos
Antioxidantes/análise , Curcuma/química , Gengibre/química , Fenóis/análise , Compostos Fitoquímicos/análise , Catecóis/análise , Álcoois Graxos/análise , Polifenóis/análise , Rizoma/química , Especiarias/análise
13.
Food Chem ; 293: 127-133, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31151592

RESUMO

Dried persimmon is thought to be a rich source of non-extractable polyphenols (NEPPs). Here, we analyzed the NEPP content of dried persimmon and its bile acid-binding activity in vitro. To determine total NEPP content and epicatechin equivalent (ECE) of intact NEPPs, acid hydrolysis and non-destructive methods with 70% (v/v) acetone-insoluble solids (AIS), respectively, were conducted using Folin-Ciocalteu reagent. The ECE of intact NEPPs exceeded 1000 mg/100 g in the non-destructive method, but total NEPP content was approximately 3900 mg/100 g with the acid hydrolysis method. Thiolysis showed that the non-extractable proanthocyanidins in dried persimmon mainly comprised epigallocatechin-gallate, epigallocatechin, epicatechin, and epicatechin-gallate. AIS from dried persimmon showed stronger bile acid-binding activity than AIS from apple, quince, and fresh astringent persimmon. These results suggest that the high content of NEPPs in dried persimmon may contribute to a strong bile acid-binding activity.


Assuntos
Ácidos e Sais Biliares/química , Diospyros/química , Polifenóis/química , Cromatografia Líquida de Alta Pressão , Diospyros/metabolismo , Frutas/química , Frutas/metabolismo , Hidrólise , Espectrometria de Massas , Molibdênio/química , Polifenóis/análise , Proantocianidinas/análise , Proantocianidinas/química , Compostos de Tungstênio/química
14.
Food Chem ; 297: 124954, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253296

RESUMO

In this study, fruits of two nectarine cultivars, harvested at commercial ripeness, were sorted into three density groups. Physicochemical parameters (mean weight, firmness, dry matter, soluble solids content, titratable acidity) and the levels of sugars, organic acids, vitamin C, polyphenols and volatiles were then determined at harvest and after ripening. A sensory ranking test was also performed on ripened nectarines to compare quality attributes (firmness, sweetness, acidity, and aroma). In both cultivars, ripened nectarines of higher density had significantly higher levels of dry matter, soluble solids content, sugars, ascorbic acid, polyphenols and volatiles. Among polyphenols, the levels of hydroxycinnamic acids were 30-40% significantly higher in nectarines of higher density. Among volatiles, levels of lactones, well-known key aroma compounds in nectarines, were also 2-3 times significantly higher in ripened fruits of higher density. Consistent with these results, nectarines of higher density were significantly ranked sweeter and more aromatic in both cultivars.


Assuntos
Frutas/química , Prunus persica/química , Açúcares/análise , Compostos Orgânicos Voláteis/análise , Ácido Ascórbico/análise , Análise de Alimentos/métodos , Qualidade dos Alimentos , Frutas/fisiologia , Humanos , Odorantes/análise , Polifenóis/análise , Paladar
15.
Food Chem Toxicol ; 131: 110594, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31226431

RESUMO

The phytochemical composition and the antioxidant and anti-inflammatory activities of a mixture of 23 plants, named Horchata, traditionally consumed in Ecuador, have been evaluated. The study was carried out using the hydroalcoholic extract (HHext) and infusion (IHext) of the horchata plant mixture. It was verified that thermal treatment affected the contents of vitamin C and carotenoids, but hardly those of polyphenols, which would be the main bioactive compounds in the infusion, the common form of preparation of horchata for consumption. Among phenolic compounds, caffeoylquinic acids, flavones and flavonols (mostly quercetin glycosides) were prominent. Both HHext and IHext extracts managed to protect RAW 264.7 macrophages against LPS-induced cytotoxic damage, increasing the levels of endogenous antioxidant enzymes and modulating the production of pro-inflammatory and anti-inflammatory cytokines. Greater protective effects were obtained for HHext compared to IHext, which was in agreement with its higher content of phenolic compounds favoured by a more efficient extraction in the hydroalcoholic medium. Nonetheless, the infusion still maintained a significant antioxidant and anti-inflammatory activity, which would support the protective effects on health traditionally attributed to its consumption by the population.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Extratos Vegetais/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Ácido Ascórbico/análise , Biomarcadores/metabolismo , Carotenoides/análise , Equador , Inflamação/induzido quimicamente , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Lipopolissacarídeos , Camundongos , Nitritos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Plantas Medicinais/química , Polifenóis/análise , Células RAW 264.7 , Temperatura Ambiente , Fator de Necrose Tumoral alfa/metabolismo
16.
Food Chem ; 293: 408-417, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31151628

RESUMO

We studied the polyphenol profile and antioxidant properties of cooked whole-wheat pasta to evaluate its effective antioxidant capacity, including changes produced by its production and in vitro digestion. The polyphenol profile was studied by HPLC-ESI-MS/MS, while the antioxidant capacity was measured by TEAC and FRAP assays. Results show that the polyphenol profile and antioxidant capacity change along the elaboration of cooked pasta, being the cooking step important to increase the release of bound polyphenols, enhancing their antioxidant properties. On the other hand, the study of the bioaccessibility of polyphenols, using an experimental model that simulates human gastrointestinal digestion and subsequent absorption, showed that only a small fraction of the starting polyphenolic compounds, mainly free polyphenols, could be absorbed by the small intestine; thus, reducing their effective antioxidant capacity. To our knowledge, this is the first report showing the bioaccessibility of hydroxybenzoic acid glucoside, hydroxybenzoic acid diglucoside, tryptophan, 6-C-glucosyl-8-C-arabinosyl-apigenin and diferulic acids.


Assuntos
Farinha/análise , Polifenóis/análise , Polifenóis/farmacocinética , Triticum/química , Antioxidantes/análise , Antioxidantes/metabolismo , Disponibilidade Biológica , Culinária , Ácidos Cumáricos/análise , Ácidos Cumáricos/farmacocinética , Digestão , Glucosídeos/análise , Humanos , Hidroxibenzoatos/análise , Absorção Intestinal , Espectrometria de Massas em Tandem , Triptofano/análise , Triptofano/farmacocinética
17.
Food Chem ; 294: 138-151, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31126446

RESUMO

A method was developed with ultra-high performance liquid chromatography-tandem mass spectrometry for the qualitative and semi-quantitative analysis of anthocyanins and anthocyanin-derived adducts in red wine. The method utilized in-source collision induced dissociation in conjunction with multiple reaction monitoring to achieve group-specific detection of the targeted compound groups. The method detected quantification marker ions instead of intact molecules and, as a result, 2D chromatographic fingerprints were produced. Altogether we could detect 18 groups of wine polyphenols, including up to 50 individual monomeric pigments together with fingerprints of three different types oligomeric proanthocyanidin-malvidin adducts. Importantly, the method was able to separate small, medium-sized and large oligomeric adducts. The quantitative and qualitative function of the method was tested with 10 model wines. Ultimately, we were able to obtain a comprehensive picture of the main pigment composition of any model wine with only a single UPLC-MS/MS analysis.


Assuntos
Antocianinas/análise , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em Tandem , Vinho/análise , Antocianinas/química , Cromatografia Líquida , Polifenóis/análise , Proantocianidinas/química
18.
Food Chem ; 294: 87-95, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31126509

RESUMO

Quinoa flour (QF) was added in wheat flour to make nutritionally fortified wheat bread (WB). Effects of QF on baking performance, antioxidant activity and digestibility of WB were studied. The results indicated that with an addition of a small amount of QF (5%) would not affect the baking performance of WB, while higher amounts of QF (10% and 15%) resulted in smaller specific volume, increased hardness and coarse porosity, since QF changed gluten secondary structure and disrupted gluten network. However, sensory evaluation showed that the flavor of WB enhanced significantly with increasing QF addition. More importantly, WB containing QF exhibited improved antioxidant activity and reduced in vitro digestibility with lower estimated glycemic index (eGI) and higher content of slowly digestible starch (SDS) and resistant starch (RS). Our findings indicate that QF-fortified bread is promising to be developed as a functional food with relatively lower eGI and more effective antioxidant properties.


Assuntos
Antioxidantes/química , Pão/análise , Chenopodium quinoa/química , Farinha/análise , Triticum/química , Chenopodium quinoa/metabolismo , Glutens/química , Glutens/metabolismo , Índice Glicêmico , Polifenóis/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/química , Paladar/fisiologia , Triticum/metabolismo
19.
J Food Sci ; 84(6): 1371-1381, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31112298

RESUMO

Industrial processing of raspberries into juice and jam results in the production of with high content of lipophilic and hydrophilic phytochemicals. Usually considered as waste, raspberry pomace is occasionally cold-pressed to recover specialty oil. However, the resulting pomace press-cake (PPC) still contains 30% to 35% of lipophilic compounds, such as essential fatty acids, tocols, phytosterols, and ellagitannins initially present in pomace. In a perspective of sustainable development, we investigate an eco-friendly process using an aqueous enzyme-assisted extraction (AEAE) to simultaneously and effectively recover lipophilic compounds and polyphenols from the PPC. The performance of different combinations of carbohydrases and proteases was compared. After selecting the best enzymatic system, a definitive screening design involving six factors was then implemented to optimize the process. Under optimized conditions, 1.2 units of thermostable alkaline protease/100 g PPC, pH 9, 60 °C, and 2 hr hydrolysis, more than 38% of total PPC lipophilic content were recovered in the aqueous medium. The recovery of polyphenols and antioxidant activity was, respectively, 48% and 25% higher than obtained by extraction with methanol/acetone/water mixture. Such an AEAE extract might prove useful in food and nutraceutical applications. PRACTICAL APPLICATION: Raspberry pomace, a food industrial by-product, is often considered as waste. However, it is a rich source of phytochemicals, such as tocols, polyphenols, and polyunsaturated fatty acids. To overcome the drawbacks of organic solvent use, an enzyme-assisted extraction process was developed as an eco-friendly alternative to recover these bioactive compounds. Definitive screening design experimental design was used to enhance polyphenols and lipophilics extraction yields while reducing process costs. This extract is an oil-in-water emulsion, with high content in antioxidant phytochemicals, which might have potential for use in nutraceutical applications. Therefore, this green process developed for the valorization of raspberry pomace is considered as a perspective of sustainable development.


Assuntos
Antioxidantes/análise , Proteínas de Bactérias , Endopeptidases , Frutas/química , Química Verde , Compostos Fitoquímicos/análise , Extratos Vegetais/química , Rubus/química , Antioxidantes/farmacologia , Emulsões , Ácidos Graxos Essenciais/análise , Indústria Alimentícia , Humanos , Taninos Hidrolisáveis/análise , Taninos Hidrolisáveis/farmacologia , Resíduos Industriais , Compostos Fitoquímicos/farmacologia , Fitosteróis/análise , Extratos Vegetais/farmacologia , Polifenóis/análise , Polifenóis/farmacologia , Tocoferóis/análise
20.
J Chromatogr A ; 1601: 255-265, 2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31103200

RESUMO

A simple and efficient low-cost matrix solid-phase dispersion (MSPD) extraction based on TiO2 nanoparticles (NPs) and diatomaceous earth has been developed for the recovery of phenolic compounds from residual brewing yeast. Experimental conditions for MSPD extraction were optimized by an experimental design approach. A screening factorial design plus replicates at the center point, followed by surface response analysis were used. The simultaneous identification and quantification of eleven main natural polyphenols: caffeic, chlorogenic, p-coumaric, 3,4-dihydroxibenzoic, trans-ferulic and gallic acids, kaempferol, myricetin, naringin, quercetin and rutin, was possible by combining MSPD and capillary liquid chromatography couple to a diode array detection system (cLC-DAD) and liquid chromatography couple to a triple quadrupole analyzer (LC-MS/MS). Moreover, residual brewing yeast extracts were evaluated in terms of DPPH (1,1-diphenyl-2 picrylhydrazyl) free radical scavenging activity. Polyphenol-nanoparticle interaction was studied by UV-vis spectroscopy and electron transmission microscopy (TEM), pointing out a stable interplay that assists phenolic isolation. The extracted polyphenol quantities were within the 3.2-1,500 µg g-1 range, and the high antioxidant activity estimated suggested that developed MSPD is a successful, simple, efficient and rapid method for the extraction and recovery of bioactive phenolic compounds, which promotes the reuse and re-evaluation of brewing yeast agri-food by-products.


Assuntos
Técnicas de Química Analítica/métodos , Nanopartículas/química , Fenóis/análise , Saccharomyces cerevisiae/química , Extração em Fase Sólida , Titânio/química , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Terra de Diatomáceas/química , Fenóis/isolamento & purificação , Polifenóis/análise , Polifenóis/química , Quercetina/análise , Espectrometria de Massas em Tandem
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