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1.
Food Chem ; 358: 129602, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33962815

RESUMO

Pu-erh teas from thousands of years' old trees (TPT) equip with both superior flavors and powerful antioxidative capacities. With UHPLC-Q-TOF-MS approach, TPTs' chemical profiles were characterized by comparing with Pu-erh teas from ecological trees (EPT). TPTs are discovered to possess higher contents of amino acids, fatty acids, phenolic acids, nucleosides and nucleobases but lower contents of flavonoids and caffeine congeners based on 117 discriminative constituents from 305 identified ones. Particularly, a series of caffeic acid congeners including ten new hydroxycinnamic acid depsides with higher contents in TPTs are discovered, and caffeic acid with a fold change of 638 is the foremost discriminative component. Furthermore, distinguishing constituent proportion including caffeic acid congeners in TPTs are found to take great responsibilities for their more powerful antioxidative abilities and superior flavors especially more aroma and pleasant bitterness. This research provides information for deciphering formation of TPTs' superior qualities based on chemical profile.


Assuntos
Antioxidantes/análise , Camellia sinensis/química , Chá/química , Antioxidantes/química , Cafeína/análise , Quimioinformática , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Análise de Alimentos/métodos , Qualidade dos Alimentos , Humanos , Hidroxibenzoatos/análise , Espectrometria de Massas , Paladar , Fatores de Tempo , Árvores
2.
Food Funct ; 12(9): 4005-4014, 2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-33978005

RESUMO

Tilia platyphyllos Scop. is a popular broad-leaved tree, native to Central and Southern Europe. Hydroethanolic extracts rich in phenolic compounds obtained from T. platyphyllos Scop. have shown in vitro antioxidant, anti-inflammatory and antitumor properties. The aim of this work was to evaluate the therapeutic properties of a hydroethanolic extract obtained from T. platyphyllos in HPV16-transgenic mice. The animals were divided into eight groups according to their sex and phenotype. Four groups of female: HPV+ exposed to linden (HPV linden; n = 6), HPV+ (HPV water; n = 4), HPV- exposed to linden (WT linden; n = 5) and HPV- (WT water; n = 4) and four groups of male: HPV+ exposed to linden (HPV linden; n = 5), HPV+ (HPV water; n = 5), HPV- exposed to linden (WT linden; n = 5) and HPV- (WT water; n = 7). The linden (Tilia platyphyllos Scop.) extract was orally administered at a dose of 4.5 mg/10 mL per animal (dissolved in water) and changed daily for 33 days. The hydroethanolic extract of T. platyphyllos consisted of protocatechuic acid and (-)-epicatechin as the most abundant phenolic acid and flavonoid, respectively, and was found to be stable during the studied period. In two male groups a significant positive weight gain was observed but without association with the linden extract. Histological, biochemical, and oxidative stress analyses for the evaluation of kidney and liver damage support the hypothesis that the linden extract is safe and well-tolerated under the present experimental conditions. Skin histopathology does not demonstrate the chemopreventive effect of the linden extract against HPV16-induced lesions. The linden extract has revealed a favourable toxicological profile; however, additional studies are required to determine the chemopreventive potential of the linden extract.


Assuntos
Antineoplásicos/farmacologia , Epiderme/patologia , Papillomavirus Humano 16 , Infecções por Papillomavirus/patologia , Extratos Vegetais/farmacologia , Tilia , Animais , Antineoplásicos/toxicidade , Catequina/análise , Feminino , Flavonoides/análise , Hidroxibenzoatos/análise , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Camundongos , Camundongos Transgênicos , Extratos Vegetais/química , Extratos Vegetais/toxicidade
3.
J Food Sci ; 86(5): 1726-1736, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33844283

RESUMO

In this work, red quinoa was successively subjected to α-amylase steaming, complex enzyme Viscozyme (R) L hydrolysis, and lactic acid bacteria (LAB) fermentation. The total phenolic compound content (TPC), flavonoid content (TFC), and antioxidant capacities of the solvent-extractable (free) and bound fractions and the individual phenolic compounds released were determined. Compared to steaming with α-amylase, enzymatic hydrolysis and fermentation of quinoa resulted in approximately 82.6, 26.9, 36.3, and 45.2% increases in the TPC (the sum of free and bound fractions), TFC, DPPH, and ORAC values, respectively. HPLC-QqQ-MS/MS analysis showed that enzymolysis and fermentation increased the content of protocatechuic acid, catechin, procyanidin B2 , and quercetin by 126.3, 101.9, 524, and 296.3%, respectively. Moreover, a major proportion of individual phenolic compounds existed as bound form. The results indicated that complex enzymatic hydrolysis and LAB fermentation were practical and useful to release promising polyphenols. This research provides a basis for the processing of quinoa beverages rich in phenolic compounds. PRACTICAL APPLICATION: In this work, liquefying with α-amylase, hydrolyzing with cellulolytic enzyme mixture, and fermenting with Lactic acid bacteria (LAB), successively, were exploited to process quinoa. This is an innovative method of quinoa processing to produce beverage products. Complex enzymatic hydrolysis and fermentation with LAB can significantly enhance phenolic compound, especially protocatechuic acid, catechin, procyanidin B2 , and quercetin. In additional, LAB fermentation is very beneficial to improve the antioxidant activity of quinoa. We also found that a major proportion of phenolic compounds existed as bound forms in quinoa.


Assuntos
Antioxidantes/análise , Chenopodium quinoa/metabolismo , Manipulação de Alimentos/métodos , Lactobacillus/metabolismo , Complexos Multienzimáticos/metabolismo , Fenóis/análise , Chenopodium quinoa/química , Fermentação , Flavonoides/análise , Hidrólise , Hidroxibenzoatos/análise , Soluções , Vapor , Água , alfa-Amilases/metabolismo
4.
Molecules ; 26(5)2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33801551

RESUMO

The bulbs of several Lilium species are considered to be both functional foods and traditional medicine in northern and eastern Asia. Considering the limited information regarding the specific bioactive compounds contributing to the functional properties of these bulbs, we compared the secondary metabolites of ten Lilium bulb samples belonging to five different species, using an ultrahigh-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS)-based secondary metabolomics approach. In total, 245 secondary metabolites were detected; further, more metabolites were detected from purple Lilium bulbs (217 compounds) than from white bulbs (123-171 compounds). Similar metabolite profiles were detected in samples within the same species irrespective of where they were collected. By combining herbal analysis and screening differential metabolites, steroid saponins were considered the key bioactive compounds in medicinal lilies. Of the 14 saponins detected, none were accumulated in the bulbs of L. davidii var. willmottiae, also called sweet lily. The purple bulbs of L. regale accumulated more secondary metabolites, and, notably, more phenolic acid compounds and flavonoids. Overall, this study elucidates the differential metabolites in lily bulbs with varying functions and colors and provides a reference for further research on functional foods and the medicinal efficacy of Lilium species.


Assuntos
Flavonoides/análise , Hidroxibenzoatos/análise , Lilium/metabolismo , Metaboloma , Extratos Vegetais/metabolismo , Raízes de Plantas/metabolismo , Cromatografia Líquida de Alta Pressão , Análise Discriminante , Lilium/química , Lilium/classificação , Raízes de Plantas/química , Espectrometria de Massas por Ionização por Electrospray
5.
Molecules ; 26(5)2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33802535

RESUMO

The attractive colour characteristics of the flowers of the species Impatiens walleriana have been arousing great interest in the food industry, which is looking for potential natural sources of colouring ingredients. In this sense, the present work focused on the chemical and bioactive characterization of pink and orange flowers of I. walleriana. The phenolic compounds were determined by HPLC-DAD-ESI/MS; in addition, different bioactivities (antioxidant, antimicrobial, anti-inflammatory and cytotoxicity) were also analysed. Both samples studied showed significant amounts of phenolic compounds, especially phenolic acids, flavonoids, and anthocyanins, which justifies the excellent performance in the different bioactivities studied. The orange variety, despite having a greater variety of phenolic compounds, showed a total amount of compounds lower than the pink variety. Overall, the flowers of I. walleriana emerge as a promising resource to be explored by the food industry.


Assuntos
Antocianinas/análise , Flavonoides/análise , Flores/química , Hidroxibenzoatos/análise , Impatiens/química , Extratos Vegetais/farmacologia , Anti-Infecciosos/farmacologia , Anti-Inflamatórios/farmacologia , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Proliferação de Células , Flores/metabolismo , Impatiens/metabolismo , Células Tumorais Cultivadas
6.
J Food Sci ; 86(5): 1878-1892, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33884623

RESUMO

Phenolic acids and phytosterols, the main functional compounds in cereals, could promote wellbeing and reduce the risks of diet-related diseases. This study aimed to demonstrate phenolic acid and phytosterol profiles in rice grains and wheat flours, and estimate their intakes in five geographical regions and among different age groups. Phenolic acids and phytosterols mainly existed in bound form, and the whole rice grain had high amount of 161.39 to 368.74 µg/g and 37.50 to 93.31 mg/ 100 g, respectively. In total, nine phenolic acids and six phytosterols were detected with ferulic and p-coumaric acid, and ß-sitosterol the most abundant. The dietary intakes of phenolic acids and phytosterols were calculated combined with the dietary foods intake data of Chinese people. The intakes of total phenolic acids and phytosterols from rice grains and wheat flours varied across different regions with Beijing the highest among the five regions. At the age of 2 to 70 years, the average intakes of phenolic acids and phytosterols from rice and wheat flours were 7.74 to 17.52 and 58.02 to 135.61 mg/sp/day, respectively. If 3-ounce of polished rice was replaced by black rice grain, the predicted intakes of total phenolic acids and phytosterols from rice grains and wheat flours would increase by at least 196% and 68%, respectively, especially for free phenolic acids and phytosterols. PRACTICAL APPLICATION: This study would help the consumers know how much phenolic acids and phytosterols they would get from 3 ounces of black rice in a reasonable intake of staple food but shift away other kinds of foods. It could also provide inspirations for food industries to explore the functional cereal foods that are rich in phenolic acids and phytosterols for different regions and different age groups.


Assuntos
Dieta , Hidroxibenzoatos/análise , Oryza/química , Fitosteróis/análise , Triticum/química , Grãos Integrais/química , Adolescente , Adulto , Idoso , Pequim , Criança , Pré-Escolar , China , Ácidos Cumáricos/análise , Grão Comestível , Farinha/análise , Humanos , Pessoa de Meia-Idade , Sitosteroides/análise
7.
Food Chem ; 353: 129446, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33735771

RESUMO

Sourness is an important food taste for human. A rapid, accurate method was used to generalize the structure similarity and diversity of sour compounds. Based on the product ion and neutral loss of sour compounds, ambient ionization techniques combined with quadrupole-Orbitrap mass spectrometry (AI-Q-Orbitrap) was employed. According to the behavior of sour compounds in the process of high collision dissociation (HCD) of MS/MS, three fragmentation pathway schemes were proposed: (1) charge-driven fragmentation and CO2 loss, (2) six-membered ring rearrangement and Cα-Cß cleavage, and (3) elimination rearrangement and H2O, CO2 and CO loss in succession. Besides, structure information about characteristic product ions and characteristic neutral losses was summarized. Finally, multi-class sour compounds including monoacids, diacids, polyacids and phenolic acids in wine and tea were identified and compared. Therefore, sour compounds and their structure information can be determined by AI-MS based on characteristic product ion and neutral loss.


Assuntos
Análise de Alimentos/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Paladar , Chá/química , Vinho/análise , Ácidos Graxos/análise , Humanos , Hidrocarbonetos Aromáticos/análise , Hidroxibenzoatos/análise , Íons/análise , Íons/química , Espectrometria de Massas em Tandem/métodos
8.
Food Chem ; 355: 129598, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33765482

RESUMO

Derivatization is usually employed in immunoassay for detection of metabolites of nitrofurans and avoiding derivatization could be preferable to achieve an efficient screening. In the study, we designed four haptens of 4-hydroxybenhydrazide (HBH), the nifuroxazide metabolite. The effect of hapten structures on antibody affinity were evaluated and one monoclonal antibody was produced by using the Hapten C with a linear alkalane spacer arm. After optimization, an enzyme linked-immunosorbent assay (ELISA) was established with an 50% inhibition concentration of 0.25 ng mL-1 for HBH, which could ensure the direct detection of HBH without derivatization. The limit of detection of the ELISA for HBH was 0.12 µg kg-1 with the recoveries of 90.1-96.2% and coefficient of variation (CV) values lower than 9.1%. In conclusion, we produced several high affinity antibodies to HBH with new designed hapten and developed an icELISA for the direct detection of HBH without derivatization in chicken.


Assuntos
Anticorpos Monoclonais/imunologia , Galinhas/metabolismo , Ensaio de Imunoadsorção Enzimática/métodos , Hidroxibenzoatos/análise , Hidroxibenzoatos/metabolismo , Nitrofuranos/metabolismo , Animais , Anticorpos Monoclonais/metabolismo , Formação de Anticorpos , Haptenos/química , Haptenos/imunologia , Concentração de Íons de Hidrogênio , Hidroxibenzoatos/imunologia , Camundongos , Concentração Osmolar , Temperatura
9.
Molecules ; 26(5)2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33669143

RESUMO

A new type of multigrain snack has been designed containing varied additions of Moldavian dragonhead (Dracocephalum moldavica L.) seeds. The antioxidant properties and the general health benefits of this plant material have already been widely acknowledged. The research discussed herein aimed to investigate the influence of the formulation and expansion method (frying) on the content of polyphenolic compounds, individual phenolic acids, and antiradical properties of innovative snacks enriched with dragonhead seeds. The highest content of polyphenols (0.685 mg GAE/mL), free phenolic acids (47.052 µg/g of dry matter), and highest radical scavenging activity (96.23% towards DPPH) were found in the fried snacks enriched with 22% of seeds. In these samples, 11 phenolic acids were detected. Strong positive correlations were seen between the addition of dragonhead and the polyphenol content (r = 0.989) and between the quantity of the enriching additive and the content of free phenolic acids (r = 0.953). The research has shown that such innovative snacks have the potential to supply health-benefiting free phenolic acids, e.g., salicylic, isoferulic, ferulic, p-coumaric, vanillic. Our studies provide an introduction to the development of a new range of functional foods.


Assuntos
Compostos de Bifenilo/análise , Alimento Funcional/análise , Hidroxibenzoatos/análise , Lamiaceae/química , Picratos/análise , Polifenóis/análise , Lanches , Extratos Vegetais/análise , Sementes/química
10.
Food Chem ; 345: 128612, 2021 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-33352407

RESUMO

In the present study, soymilk samples were prepared from 15 soybean varieties by employing dry method-raw slurry filtration (D-BAF), dry method-cooked slurry filtration (D-BBF), wet method-raw slurry filtration (W-BAF), and wet method-cooked slurry filtration (W-BBF). Different varieties of soybean and processing techniques were found to impose a significant impact on total phenolics, total flavonoids, phenolic acids, isoflavones and antioxidant capacity of soymilk samples. Overall, the soymilk prepared by W-BAF exhibited a higher level of total phenolic content and antioxidant activity. The soymilk samples prepared by W-BBF presented higher values for total flavonoid content and ferric-reducing antioxidant power assay. The soymilk prepared by W-BBF presented higher subtotal values of phenolic acids. In comparison, the soymilk prepared by D-BAF exhibited high amount of total isoflavones followed by the soymilk processed by W-BAF. Overall, the wet method was found to be responsible for improved phenolic contents and antioxidant activity of soymilk sample.


Assuntos
Antioxidantes/análise , Manipulação de Alimentos/métodos , Hidroxibenzoatos/análise , Isoflavonas/análise , Leite de Soja/química , Soja/química , Análise de Alimentos
11.
Food Chem ; 345: 128732, 2021 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-33341558

RESUMO

Edible wild plants are part of the ethnobotanical and gastronomic heritage of different geographical areas. Corema album (L.) D. Don is an endemic species of the dune systems of the Atlantic coast of the Iberian Peninsula. The aerial parts of Corema album are a source of nutrients and antioxidants. The Corema album white berry (Portuguese crowberry) is rich in calcium, iron, and zinc. The plant also shows high phenolic content and antioxidant capacity associated with the leaves, fruit, and flowers. The presence of organic acids, namely phenolic acids, such as hydroxycinnamic acids, and long chain polyunsaturated fatty acids (PUFAs) omega-3 and omega-6 has also been confirmed. Toxicity studies evaluated by cell viability tests with human intestinal epithelium model cells (Caco-2) have shown that, at low concentrations, plant extracts may present beneficial effects.


Assuntos
Ericaceae/química , Hidroxibenzoatos/análise , Minerais/análise , Plantas Comestíveis/química , Antioxidantes/análise , Células CACO-2 , Frutas/química , Humanos , Extratos Vegetais/toxicidade , Folhas de Planta/química
12.
Food Chem ; 340: 127910, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32882475

RESUMO

The aim of this study is to monitor the evolution of the principal phenolic compounds throughout the fermentation stage of white wines treated with different enzymes. The effect of five commercial enzymes on the evolution of the phenolic profile during the alcoholic fermentation of white wines obtained from Feteasca regala and Sauvignon blanc varieties was evaluated. Physicochemical properties of resulted wine samples have been analyzed according to OIV standards and regulations. The evolution of the principal phenolic compounds was carried out using HPLC method. Enzymatic treatments did not significantly affect the physicochemical composition of the obtained wines. The analyzed samples showed different variations on the phenolic compound content, depending on the type of added enzyme and grape variety. The statistical analysis confirms that enzymes significantly contributed to the enrichment of the wines with phenolic compounds, especially with p-coumaric, gentisic, caftaric, and protocatechuic acids.


Assuntos
Enzimas/metabolismo , Fenóis/análise , Vitis/química , Vinho/análise , Cromatografia Líquida de Alta Pressão , Enzimas/química , Fermentação , Hidroxibenzoatos/análise , Fenóis/química , Fenóis/metabolismo , Vitis/microbiologia , Vinho/microbiologia
13.
Food Chem ; 340: 127908, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32889206

RESUMO

This study aims to evaluate the effects of in vitro digestion of rice and common bean blends on phenolics content and profile. Black and carioca beans were used as common bean sources. Blends consisted of 25:75, 50:50, and 75:25 polished rice:beans (w/w). Pure rice or pure beans were also analyzed. Phenolic compounds were determined in raw, cooked, and digested samples. The glucose release through in vitro digestion was slower as the proportion of black beans or carioca beans increased. Starch digestibility ranged between 41.1 in 100% carioca bean to 84.4% in 100% rice. Hydroxybenzoic acid, ferulic acid, p-coumaric acid, catechin, and epicatechin were the most abundant phenolics detected in the studied samples. Considering the content of phenolic compounds determined in the raw, cooked, and digested grains, only a small fraction was available for absorption in the gut, with amounts varying from 0.1 to 0.6 µg·g-1.


Assuntos
Oryza/química , Phaseolus/química , Fenóis/análise , Amido/química , Amido/farmacocinética , Catequina/análise , Catequina/química , Culinária , Digestão , Glucose/farmacocinética , Hidroxibenzoatos/análise , Hidroxibenzoatos/química , Fenóis/química , Amido/análise
14.
Food Chem ; 340: 127983, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32919354

RESUMO

This study aims at determining the potentials of cinnamon (Cinnamomun burmannii) extracts to improve the health-promoting properties of white chocolate. LC-HRMS analysis was employed to obtain information regarding the phytochemical content while the phosphomolybdenum, FRAP and DPPH assays were used to determine antioxidant activity of cinnamon extract. Furthermore, the cinnamon extract was loaded into nanoparticles before adding it to white chocolate. The results show that cinnamon extracts contained phenols up to 310 mg EE and possessed antioxidant activity up to 260 mg TAE per gram of dry extract depending on the extraction mode (i.e., traditional and ultrasonic-assisted method) and the solvent type. The cinnamon extract contained catechin, epicatechin, procyanidin B2, quercitrin, 3,4-dihydroxybenzaldehyde, protocatechuic acid and cinnamic acid at levels of 51, 53, 1396, 13, 1138, 228 and 934 µg/g of dry extract, respectively. The encapsulated cinnamon extract increased the phenolic content of white chocolate from 47.6 to 1060.6 µg EE/g.


Assuntos
Antioxidantes/química , Chocolate , Cinnamomum zeylanicum/química , Compostos Fitoquímicos/análise , Extratos Vegetais/química , Biflavonoides/análise , Catequina/análise , Chocolate/análise , Microscopia Crioeletrônica , Indústria de Processamento de Alimentos , Hidroxibenzoatos/análise , Fenóis/análise , Extratos Vegetais/análise , Proantocianidinas/análise , Quercetina/análogos & derivados , Quercetina/análise , Ultrassom
15.
Food Chem ; 340: 128123, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33010645

RESUMO

Six commercial red sorghum varieties (Tong Za 117, 141, 142 and 143, Chi Za 109 and 101) were investigated for their triacylglycerol (TAG) profiles, soluble and bound phenolics, and radical scavenging and anti-inflammatory activities. A total of 21 TAGs were identified in red sorghum oils for the first time. Total phenolic (TPC) and flavonoid contents (TFC) in the soluble or bound phenolic fractions differed among red sorghums. Significant correlation among TPC, TFC and DPPH radical scavenging activities was observed in both fractions. Except for caffeic acid, most of phenolic acids in red sorghums are in the bound form. Soluble 3-deoxyanthocyanidins contents (2.12-57.14 µg/g) were significantly higher than those of bound forms (0.01-0.18 µg/g) regardless of sorghum varieties and types of 3-deoxyanthocyanidins. Moreover, the stronger anti-inflammatory capacity of soluble phenolic fraction in Tong Za 117 correlated with its higher TPC, TFC and radical scavenging activity than those of its bound counterpart.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Sequestradores de Radicais Livres/farmacologia , Sorghum/química , Triglicerídeos/análise , Triglicerídeos/farmacologia , Animais , Anti-Inflamatórios não Esteroides/química , Antioxidantes/química , Ácidos Cafeicos/análise , Ácidos Cafeicos/química , Diterpenos/análise , Flavonoides/análise , Sequestradores de Radicais Livres/química , Hidrólise , Hidroxibenzoatos/análise , Hidroxibenzoatos/química , Camundongos , Fenóis , Extratos Vegetais/química , Óleos Vegetais/análise , Óleos Vegetais/química , Células RAW 264.7
16.
Food Chem ; 340: 128183, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33032151

RESUMO

Non-centrifugal cane sugar (NCS) samples obtained by traditional moulding and granulation, and also via a novel spray-drying powdering process without additives, were assessed to characterise their sugar and phenolic profiles, flavonoid content, as well as colour parameters. As expected, sucrose was the predominant sugar (91.9-95.5%), followed by glucose (2.9-4.6%), and fructose (1.6-3.7%). Total phenolic content was between 0.4 and 0.6% and total flavonoid content into the range of 0.2-0.4%. Six phenolic acids were found in all NCS samples: protocatechuic acid (0.36-0.94 µg/100 g), vanillic acid (0.70-1.45 µg/100 g), chlorogenic acid (2.08-3.82 µg/100 g), syringic acid (1.08-2.80 µg/100 g), p-coumaric acid (0.69-1.35 µg/100 g), and ferulic acid (0.50-0.95 µg/100 g). The thermal treatment under high temperatures required in the production of granulated products was related with darker colours and changes in phenol and flavonoid contents. In contrast, spray drying generates clearer products, but with slightly less phenol and flavonoid contents.


Assuntos
Colorimetria , Manipulação de Alimentos , Açúcares/química , Antioxidantes/análise , Ácidos Cumáricos/análise , Flavonoides/análise , Hidroxibenzoatos/análise , Fenóis/análise
17.
Food Chem ; 335: 127655, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32731125

RESUMO

In the present study, the profile of phenolic compounds in colored (white, yellow, black and blue) naked barley was detected and their content and antioxidant abilities were investigated. The results showed that there were 156 phenolic substances identified, including monophenol, phenolic acids, flavonoids and other polyphenols. The black sample had the most types of phenolic. The content of phenolic varies depending on color of naked barley and the highest values of total phenolic acid and total flavonoids were observed in black and white samples. Furthermore, the strongest ferric reducing antioxidant power and the free radical scavenging ability of DPPH, ABTS, and superoxide anion showed in white, white, yellow and black naked barley. While white and yellow samples had the strongest scavenging ability of hydroxyl radical. There was significant correlation between phenolic components and anti-oxidation. This study suggests that colored naked barley grains are rich in phenolic compounds with antioxidant capacity.


Assuntos
Antioxidantes/análise , Antioxidantes/química , Hordeum/química , Fenóis/análise , Sementes/química , Compostos de Bifenilo/química , Flavonoides/análise , Sequestradores de Radicais Livres/química , Hidroxibenzoatos/análise , Radical Hidroxila/química , Oxirredução , Picratos/química , Pigmentação , Polifenóis/análise , Superóxidos/química
18.
Sci Rep ; 10(1): 21972, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33319819

RESUMO

The effects of ultraviolet-C light (UVC) on vitamin C and phenolic compounds in acerola during postharvest storage were investigated in order to elucidate the mechanism inducing the antioxidant systems. The fruits, stored at 10 °C for 7 days after a hormetic UVC irradiation (two pulses of 0.3 J/cm2), showed significantly less degradation of vitamin C and phenolic compounds than the control without the UVC challenge. UVC activated the L-galactono-1,4-lactone dehydrogenase (GalDH), a key enzyme for vitamin C biosynthesis, and altered the composition of phenolic compounds, through phenolic biosynthesis, in acerola during postharvest storage. UVC also induced reactive oxygen species (ROS) productions at immediate (day 0) and late (day 7) times during postharvest storage through the mitochondrial electron transport chain and NADPH oxidase, respectively. Results suggest that UVC helps in the retention of vitamin C and phenolic content in acerola by altering ascorbic acid and phenolic metabolism through an increase in mitochondrial activity and a ROS-mediated mechanism. Data showed the beneficial effects of UVC on maintenance of nutraceutical quality in acerola during postharvest storage and supplied new insights into understanding the mechanism by which UVC irradiation enhance the antioxidant system in fruits.


Assuntos
Ácido Ascórbico/biossíntese , Malpighiaceae/metabolismo , Malpighiaceae/efeitos da radiação , Mitocôndrias/metabolismo , Fenóis/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Raios Ultravioleta , Ácido Ascórbico/metabolismo , Vias Biossintéticas , Catecol Oxidase/metabolismo , Flavonoides/análise , Regulação da Expressão Gênica/efeitos dos fármacos , Hidroxibenzoatos/análise , Mitocôndrias/efeitos da radiação , Modelos Biológicos , NADPH Oxidases/metabolismo , Oxirredutases/metabolismo , Fenilalanina Amônia-Liase/metabolismo
19.
PLoS One ; 15(8): e0238061, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32846429

RESUMO

The method of non-aqueous conductivity titration (NACT) of organic weak acids was applied to quickly and accurately determine the phenolic-hydroxyl and carboxyl-groups contents in humic acid. By varying the pH of the humic-acid sample, the concentration of the titrant, and the nitrogen-gas flow rate, the optimal titration conditions were determined to be a sample pH of 4, titrant concentration of 0.05 mol/L, and nitrogen-gas flow rate of 80 mL/min. Applying the detection method to p-hydroxybenzoic acid showed that its phenolic-hydroxyl content was 758.82±111.76 cmol/kg and carboxyl content was 744.44±51.11 cmol/kg. The theoretical phenolic-hydroxyl and carboxyl-groups contents of the p-hydroxybenzoic acid were 723.96 cmol/kg respectively, indicating that the method can accurately quantify the carboxyl and phenolic-hydroxyl groups in the sample. The NACT was used to measure the phenolic-hydroxyl and carboxyl-groups contents in humic acid quickly and accurately. In addition, 29 humic acid samples from 8 provinces of China covering the main humic-acid producing areas were collected and analyzed for acidic-groups content using the reported method.


Assuntos
Técnicas Eletroquímicas/métodos , Substâncias Húmicas/análise , China , Condutividade Elétrica , Eletrodos , Concentração de Íons de Hidrogênio , Hidroxibenzoatos/análise , Fenóis/química , Solo/química
20.
Food Chem ; 330: 127266, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32540528

RESUMO

The present study aimed to characterize the nutritional value and potential use of elderberries as a source of antioxidant compounds. The chemical composition, fatty acids and phenolic compounds were determined for elderberries. The optimization of extraction parameters was designed with a Box-Behnken design coupled with response surface methodology (RSM) and desirability function analysis. The process parameters tested included extraction temperature, % of ethanol and pH, while response variables were global extraction yield, total phenolic and anthocyanins content (TAC), carotenoids and antioxidant activity. Analyses revealed that elderberry was a rich source of total soluble solids, proteins and polyunsaturated fatty acids (omega-3: 38.12 g/100 g and omega-6: 39.54 g/100 g fatty acids). Regarding phenolic compounds, elderberries were found abundant in flavonoids (rutin and quercetin), and phenolic acids (i.e. gallic acid and gentisic acid). Finally, numerical optimization indicated that the best extraction parameters were the following: temperature 60 °C, 50% of ethanol and pH 2.


Assuntos
Antioxidantes/análise , Antioxidantes/química , Sambucus nigra/química , Antocianinas/análise , Carotenoides/análise , Fracionamento Químico , Etanol/química , Flavonoides/análise , Análise de Alimentos/métodos , Ácido Gálico/análise , Concentração de Íons de Hidrogênio , Hidroxibenzoatos/análise , Valor Nutritivo , Fenóis/análise , Extratos Vegetais/química , Quercetina/análise , Solventes , Espectrometria de Massas em Tandem , Temperatura
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