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1.
PLoS One ; 15(9): e0229841, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32946470

RESUMO

Starch based gluten-free bread (formulations containing mixture of corn and potato starch with hydrocolloids) are deficient in nutrients and do not contain health promoting compounds. Therefore they could be supplemented with raw materials rich in such components, especially antioxidants. Among them pseudo-cereals, seeds, fruits and vegetables are often applied to this purpose. Potato pulp produced by processing red fleshed (Magenta Love) and purple fleshed (Violetta) varieties could become a new innovative substrate for gluten-free bread enrichment, because of high levels of endogenous polyphenols, namely flavonoids, flavonols, phenolic acids and especially anthocyanins with high antioxidant potential, as well as dietary fiber. Study material consisted of gluten-free bread enriched in the pulp. Dietary fiber, acrylamide content and antioxidant and antiradical potential of the bread were determined. Sensory evaluation included crumb elasticity, porosity and other characteristics, taste and smell. Among all analyzed gluten-free breads, the sample containing 7.5% share of freeze-dried red potato pulp Magenta Love was characterized by high content of phenolic compounds and dietary fiber, pronounced antioxidant activity, low levels of potentially dangerous acrylamide and good physical and sensory characteristics. Therefore such an addition (7.5% Magenta Love) could be recommended for industrial production of gluten-free bread.


Assuntos
Pão , Farinha/análise , Ingredientes de Alimentos/análise , Solanum tuberosum/química , Verduras/química , Acrilamida/análise , Antioxidantes/análise , Doença Celíaca/dietoterapia , Doença Celíaca/imunologia , Fibras na Dieta/análise , Liofilização/métodos , Glutens/imunologia , Humanos , Valor Nutritivo , Polifenóis/análise , Porosidade , Olfato , Amido/isolamento & purificação , Paladar
2.
PLoS One ; 15(8): e0237265, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32841240

RESUMO

Roasting is the most common method of processing coffee. During roasting, aromatic compounds are generated due to various reactions, which are important for developing color, flavor and aroma. Acrylamide is an undesirable carcinogenic substance that is metabolically activated and formed during the coffee roasting process. Coffea arabica was first found in Ethiopia, and Ethiopia can produce a large volume of coffee. The major coffee-producing areas in Ethiopia are Hararghe, Sidama, Gimbi/Nekemte, Yergachefe and Limu. The primary purpose of this study was to quantify the acrylamide contents of brewed and roasted coffee collected from street coffee sellers and industrial processors found in Addis Ababa, Ethiopia, and optimize the roasting conditions for Sidama coffee. The acrylamide contents were determined by HPLC using a DAD at 210 nm, the antioxidant property were examined using a UV-spectrophotometer, and moisture and nutrient composition of coffee was determined using the method described by the AOAC (Association of Official Analytical Chemists). The roasting temperature and time were optimized based on the acrylamide content, nutritional composition and antioxidant property of the coffee using central composite design. The roasting temperature and time significantly affected (p<0.05) the acrylamide level, nutritional composition and antioxidant property of the coffee. The acrylamide contents of street and industrial processed powdered coffee were 346 ±19 to 701±38µg/kg and 442±14 to 906±7µg/kg, respectively. Brewed coffee from street vendors and industrial processing had acrylamide contents of 25±2 to 49±1µg/L and 63±2 to 89±4µg/L, respectively. The EC50 values for scavenging radicals for the optimized coffee ranged from 171±0 to 111±4 µg/L. The optimal roasting temperature and time were 190°C and 6 minutes, at this temperature and time the acrylamide content decreased, and the antioxidant and nutritional compositions of the coffee improved.


Assuntos
Acrilamida/análise , Antioxidantes/análise , Coffea/química , Café/química , Nutrientes/análise , Manipulação de Alimentos/métodos , Tecnologia de Alimentos/métodos , Temperatura Alta , Sementes/química
3.
J Oleo Sci ; 69(9): 1133-1138, 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32788514

RESUMO

To identify antioxidants for improving rough skin, we aimed to analyze the amino acid composition of fish mucus and antioxidant activity of the mucus component. Specifically, we aimed to examine the antioxidant properties of dialyzed mucus components secreted from mackerel, which can be used as raw materials for producing cosmetics. The amino acid composition of hydrolyzed mucus was examined by ultra-high-performance liquid chromatography after dialyzing mucus. In addition, the antioxidant activity of the mucus was evaluated via oxygen radical absorption capacity and Trolox equivalent antioxidant capacity assays. The amino acid composition differed between the low-molecular-weight and high-molecular-weight fractions. Moreover, the low-molecular-weight fraction of farmed mackerel mucus exhibited antioxidant activity with high specificity. The results suggest that antioxidant peptides or free amino acids are present in the low-molecular-weight fraction of farmed mackerel mucus.


Assuntos
Aminoácidos/análise , Antioxidantes/análise , Cosméticos , Muco/química , Aminoácidos/farmacologia , Animais , Cromatografia Líquida de Alta Pressão , Histidina , Metionina , Peso Molecular , Perciformes , Selenometionina
4.
J Chromatogr A ; 1625: 461276, 2020 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-32709328

RESUMO

The monodisperse pillar[5]arene-based polymeric sub-microsphere was prepared by polycondensation of hydroxylated pillar[5]arene and cyanuric chloride through a one-pot reaction in mild condition. The preparation was realized by a simple two-step temperature-programmed process without heating operation. The obtained polymeric sub-microsphere exhibited monodisperse and regular spherical structure with uniform particle size distribution of 220-320 nm accounting for 94%. The prominent adsorption capacity of the polymeric sub-microsphere for antioxidants was demonstrated and attributed to the synergistic effect of the cladding interaction with the π-electron rich cavity and hydrophilic interaction with terminal hydroxyl on pillar[5]arene. Then the pillar[5]arene sub-microsphere was packed into a micro-column to realize effective on-line enrichment of antioxidants coupling with high-performance liquid chromatography (HPLC). The flow rate of extraction and desorption solvent, clean-up and desorption volume were assessed to optimize the method. The method showed wide linear ranges with R2 greater than 0.9926, low limits of detection (0.030-0.20 µg/L) and limits of quantification (0.10-0.67 µg/L). The developed method was successfully applied to determine trace antioxidants in the migration of food contact materials with simulated solution, which demonstrated the promising potential of this method for practical analysis. Furthermore, the migration behavior of antioxidants from food packaging materials into different food matrix was also investigated.


Assuntos
Antioxidantes/análise , Calixarenos/química , Cromatografia Líquida de Alta Pressão/métodos , Embalagem de Alimentos , Microesferas , Sistemas On-Line , Polímeros/química , Adsorção , Bebidas/análise , Interações Hidrofóbicas e Hidrofílicas , Tamanho da Partícula , Reprodutibilidade dos Testes , Solventes
5.
Chemosphere ; 260: 127519, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32683033

RESUMO

Limited studies focus on the occurrence, removal rate and seasonal variation of substituted diphenylamine antioxidants (SDPAs) in surface water and wastewater in China. In this paper, the detection method of SDPAs was established by the ultra-performance liquid chromatography-tandem mass spectrometry. Daily variations suggested that significant variations were found for the concentrations of some SDPAs in the influent. It was found that the SDPAs could be detected in all the effluent samples and C8/C8-DPA was the predominant compound in two WWTPs. The levels of most SDPAs in the effluent were much lower than that of influent, with the removal efficiencies of total SDPAs ranged from 57.9% to 84.2%. There were significant differences with the SDPA concentrations in the influent between different seasons. Higher concentrations of SDPAs were found at downstream than those of upstream. The results of this study provide more environmental occurrence data and new insights into the research on the environmental fate of these compounds.


Assuntos
Antioxidantes/análise , Difenilamina/análise , Monitoramento Ambiental/métodos , Rios/química , Águas Residuárias/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , China , Estações do Ano
6.
Food Chem ; 333: 127410, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32682227

RESUMO

Insects represent a novel source of edible high nutritional value proteins which are gaining increasing interest as an alternative to traditional animal foods. In this work, cricket flour was used to produce gluten-free sourdough breads, suitable for celiac people and "source of proteins". The doughs were fermented by different methods and pH and microbial growth, volatile compounds, protein profile, and antioxidant activity, before and after baking, were analyzed and compared to standard gluten-free doughs. The results showed that cricket-enriched doughs and the standard had similar fermentation processes. Cricket enrichment conferred to the breads a typical flavoring profile, characterized by a unique bouquet of volatile compounds, made by nonanoic acid, 2,4-nonadienal (E,E), 1-hexanol, 1-heptanol, and 3-octen-2-one, expressed in different amounts depending on the type of inoculum. Finally, antioxidant activities were significantly enhanced in cricket breads, indicating that cricket powder provides to bakery gluten-free goods high nutritional value proteins and antioxidant properties.


Assuntos
Antioxidantes/análise , Pão/análise , Dieta Livre de Glúten , Farinha/análise , Proteínas de Plantas/análise , Pão/microbiologia , Fermentação , Farinha/microbiologia , Concentração de Íons de Hidrogênio
7.
J Environ Sci Health B ; 55(9): 813-819, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32602767

RESUMO

The use of vegetable waste and its screening for potential cytotoxicity is of utmost importance to ensure its safe use in the feed industry for fish and other animals. We evaluated aqueous and ethanolic extracts of cooked Araucaria angustifolia seed coats. The Stiasny index for the aqueous and ethanolic extracts was 2.87% ± 0.03% and 60.53% ± 4.79%, respectively. Condensed tannins were 11-fold higher in the ethanolic extract than the aqueous extract. The flavonoid and polyphenol contents were 1.7- and 1.8-fold higher in the ethanolic extract than in the aqueous extract, respectively. The 36 h EC50 for brine shrimp hatchability was 300.32 µg/mL for the aqueous extract, and 76.60 µg/mL for the ethanolic extract. The 24 h LC50 was 1405.96 µg/mL for the aqueous extract, and it was 356.32 µg/mL for the ethanolic extract. The aqueous extract was nontoxic to A. salina nauplii, and therefore, it can be used as a possible food additive in fish feed. The results also demonstrated that the different solvents used in the extraction affected the yield and the total phenolic, total flavonoid, and condensed tannin content. Further in vivo and cell line cytotoxicity testing is recommended to substantiate these findings.


Assuntos
Araucaria/química , Artemia , Extratos Vegetais/toxicidade , Sementes/química , Ração Animal , Animais , Antioxidantes/análise , Artemia/efeitos dos fármacos , Artemia/fisiologia , Culinária , Flavonoides/análise , Dose Letal Mediana , Fenóis/análise , Extratos Vegetais/análise , Extratos Vegetais/química , Polifenóis/análise , Solventes/química , Taninos/análise , Testes de Toxicidade
8.
PLoS One ; 15(7): e0236357, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32687509

RESUMO

Adult growth hormone deficiency (GHD) is being increasingly recognized to cause premature mortality exacerbated by oxidative stress. A case-control observational study has been performed with the primary objective of evaluating new parameters of oxidative stress and macromolecular damage in adult GHD subjects: serum nitrotryptophan; Total Antioxidant Capacity expressed as LAG time; urinary hexanoil-lysine; urinary dityrosine and urinary 8-OH-deoxyguanosine. GHD was diagnosed using Growth Hormone-Releasing Hormone 50µg iv+arginine 0,5 g/Kg test, with a peak GH response <9 µg /L when BMI was <30 kg/m2 or <4 µg/L when BMI was >30 kg/m2. Patients affected by adult GHD were divided into three groups, total GHD (n = 26), partial GHD (n = 25), and controls (n = 29). Total Antioxidant Capacity, metabolic and hormonal parameters have been determined in separate plasma samples; nitrotryptophan in serum samples; hexanoil-lysine, dityrosine, 8-OH-deoxyguanosine in urine samples. Assessment of hexanoil-lysine exhibited a trend to increase in comparing total GHD vs partial and controls, although not significant. Values of 8-OH-deoxyguanosine did not significantly differ among the three groups. Significant lower levels of dityrosine in partial GHD vs total and controls were found. No significant difference in nitrotriptophan serum levels was found, while significantly greater values of Total Antioxidant Capacity were showed in total and partial GHD vs controls. Thus, our result confirm that oxidative stress is increased both in partial and total adult GHD. The lack of compensation by antioxidants in total GHD may be connected to the complications associated to this rare disorder.


Assuntos
Antioxidantes/análise , Hormônio do Crescimento Humano/deficiência , Hipopituitarismo/metabolismo , Síndrome Metabólica/metabolismo , Estresse Oxidativo/fisiologia , 8-Hidroxi-2'-Desoxiguanosina/urina , Adulto , Malformação de Arnold-Chiari/sangue , Malformação de Arnold-Chiari/complicações , Malformação de Arnold-Chiari/metabolismo , Biomarcadores/sangue , Biomarcadores/urina , Estudos de Casos e Controles , Síndrome da Sela Vazia/sangue , Síndrome da Sela Vazia/complicações , Síndrome da Sela Vazia/metabolismo , Feminino , Humanos , Hipopituitarismo/sangue , Hipopituitarismo/etiologia , Hipopituitarismo/urina , Peroxidação de Lipídeos , Lisina/sangue , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/etiologia , Síndrome Metabólica/urina , Pessoa de Meia-Idade , Triptofano/análogos & derivados , Triptofano/sangue , Tirosina/análogos & derivados , Tirosina/urina
9.
Arch Microbiol ; 202(9): 2533-2542, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32656677

RESUMO

The aim of this study was to evaluate the phytochemical constituents, antioxidant, antifungal, and anti-virulence activities of traditionally used Mezoneuron benthamianum leaves. Extracts were prepared using acetone and methanol, and the preliminary phytochemical screening was performed. The antioxidant activity was studied using the DPPH method. Anti-Candida albicans activity was established and the effect on the germ tube and phospholipase production, as well as on the host cell adherence was assessed. The extracts showed the presence of anthraquinones, cardiac glycosides, flavonoids, reducing sugars, saponins, steroids, tannins, and terpenoids. Gallic acid and trans-resveratrol were among the predominant phytochemicals found in M. benthamianum. The crude extracts presented significantly higher antioxidant activity than the ascorbic acid standard. At 0.39 mg/mL, acetone extract inhibited the growth of Candida albicans. At lower concentrations (200-50 µg/mL), it significantly inhibited the adherence ability (up to 51%), formation of hyphae (up to 65%), and the production of phospholipase. In conclusion, at high concentrations, M. benthamianum kills C. albicans, and at lower concentrations, it can inhibit the virulence properties of this pathogen. This study on crude extract validates the traditional use of this plant. However, further research is required to establish the anti-virulence activity of the two compounds and their therapeutic potential.


Assuntos
Candida albicans/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Fabaceae/química , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Hifas/efeitos dos fármacos , Extratos Vegetais/farmacologia , Antifúngicos/farmacologia , Antioxidantes/análise , Fosfolipases/genética , Fosfolipases/metabolismo , Extratos Vegetais/química , Folhas de Planta/química , Taninos
10.
Food Chem ; 332: 127392, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32623126

RESUMO

The present work describes a novel and rapid approach for evaluating total phenolic compounds (TPCs) in tea and fruits using colorimetric spots and the digital image-based (DIB) method. Colorimetric spots were formed by reacting diazotized aminobenzenes namely sulfanilic acid, sulfanilamide, or aniline with TPCs in the extract to form an azo dye. The limit of detection (LOD) was 6.5, 5.5, or 5.1 mg GAE (gallic acid equivalent) L-1 and the analytical range was 25-500, 20-500, or 18-200 mg GAE L-1, respectively. Correlation with the Folin-Ciocalteu assay was significant (Pearson coefficient, R = 0.970-0.991) while the antioxidant activity assay was moderate to high (R = 0.737-0.977). The method developed was successfully applied to the analysis of tea and fruits and showed RSD (n = 3) not exceeding 9.6, 8.5, and 9.7%, respectively. Ecologically, the DIB method developed could determine the variation of TPCs within cultivars and was found to be strongly dependent on the growing environment.


Assuntos
Benzeno/química , Colorimetria/métodos , Análise de Alimentos/métodos , Frutas/química , Fenóis/análise , Chá/química , Antioxidantes/análise , Limite de Detecção
11.
Arch Microbiol ; 202(10): 2679-2687, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32719949

RESUMO

Some studies focused on metabolic relationships between plants and their endophytic bacterial associates, and more research is required to generate critical evidence for these relationships. In the current interest, we tried to confirm the relationship between the traditional medicinal plant, Calotropis procera (Aiton) W.T. Aiton, and its associated endophytes, Bacillus siamensis and Bacillus amyloliquefaciens, as the first matching study regarding the production of bioactive secondary metabolites from the plant vis-a-vis its bacterial endophytes.Secondary metabolites of both the plant and its endophytic bacteria were extracted using different solvents, e.g., water, methanol, and ethyl acetate. All extracts exhibited high quantities of phenolics, flavonoids, tannins, and saponins. In addition, they showed significant antioxidant capacity which was found to be positively correlated with total phenolic contents. The highest total antioxidant capacity (99.28 ± 0.0 mg AA equivalent/g extract) was measured for the aqueous extract of B. siamensis.Antibacterial activity of the different extracts was evaluated against certain pathogenic bacteria, i.e., Escherichia coli, Klebsiella pneumoniae, Streptococcus agalactiae, Salmonella typhi, Serratia marcescens, and Staphylococcus aureus. It was strikingly found that the broadest antibacterial spectrum was revealed by extracts of both C. procera and its endophytic B. siamensis. Interestingly, antibacterial activity was significantly correlated to phenolic and flavonoid contents.


Assuntos
Bacillus amyloliquefaciens/química , Bacillus/química , Calotropis/química , Calotropis/microbiologia , Plantas Medicinais/química , Plantas Medicinais/microbiologia , Antibacterianos/química , Antibacterianos/farmacologia , Antioxidantes/análise , Bacillus/fisiologia , Bacillus amyloliquefaciens/fisiologia , Bactérias/efeitos dos fármacos , Endófitos/química , Endófitos/fisiologia , Flavonoides/análise , Testes de Sensibilidade Microbiana , Fenóis/análise , Extratos Vegetais/química , Staphylococcus aureus , Taninos/análise
12.
PLoS One ; 15(6): e0234435, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32574221

RESUMO

This study was designed to investigate the antioxidant properties of the extracts and subfractions of various polarities from Clerodendrum cyrtophyllum Turcz leaves and the related phenolic compound profiles. The ethyl acetate fraction (EAF) showed the most potent radical-scavenging activity for DPPH radicals, ABTS radicals, and superoxide anion (O2·-) radicals as well as the highest reducing power of the fractions tested; the n-butyl alcohol fraction (BAF) was the most effective in scavenging hydroxyl radical (OH·), and the dichloromethane fraction (DMF) exhibited the highest ferrous ion chelating activity. Twelve phenolic components were identified from the EAF of C. cyrtophyllum. Additionally, acteoside (1) was found to be a major component (0.803 g, 0.54%) and show DPPH and ABTS radical scavenging activities with IC50 values of 79.65±3.4 and 23.00±1.5 µg/ml, indicating it is principally responsible for the significant total antioxidant effect of C. cyrtophyllum. Our work offers a theoretical basis for further utilization of C. cyrtophyllum as a potential source of natural, green antioxidants derived from plants.


Assuntos
Antioxidantes/farmacologia , Clerodendrum/química , Glucosídeos/farmacologia , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Antioxidantes/análise , Antioxidantes/isolamento & purificação , Glucosídeos/análise , Glucosídeos/isolamento & purificação , Radical Hidroxila/metabolismo , Fenóis/análise , Fenóis/isolamento & purificação , Extratos Vegetais/análise , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Superóxidos/metabolismo
13.
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
14.
Food Chem ; 331: 127293, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32554311

RESUMO

Wild rice (Zizania spp.), an important aquatic cereal grain in North America and East Asia, has attracted interest worldwide because of its antioxidant activities and health-promoting effects. Wild rice is high in protein, minerals, and vitamins but is low in fat. The phytochemical content (phytosterols, γ-oryzanol, γ-aminobutyric acid, phenolic acids, and flavonoids) of wild rice warrants its development as a functional food. Phenolic acids, flavonoids, and other phytochemicals from Zizania plants have pronounced antioxidant properties, which are associated with prevention of chronic diseases. The health-promoting effects of Zizania plants include alleviation of insulin resistance and lipotoxicity, atherosclerosis prevention, and anti-inflammatory, anti-allergic, anti-hypertensive, and immunomodulatory effects. Here, we provide an overview of Zizania research up to April 2020, focusing on the nutritional constituents, phytochemicals, antioxidant activities, and health-promoting effects of Zizania plants. This review has important implications for further investigations and applications of Zizania plants in medicine and as functional foods.


Assuntos
Antioxidantes/análise , Saúde , Valor Nutritivo , Compostos Fitoquímicos/análise , Poaceae/química , Antioxidantes/química , Compostos Fitoquímicos/química
15.
Food Chem ; 331: 127333, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32590265

RESUMO

Flours obtained from unripe and ripe inajá palm tree fruit pulp, as well as co-products that were generated after oil extraction, were evaluated for the first time. In addition, the oils extracted using ethanol as a solvent were also analyzed. The oils showed similar thermal characteristics, such as thermal stability up to about 253 °C, while also presenting a rich composition of phenolic compounds, antioxidant capacity and carotenoid content. Concerning the raw flours and their defatted counterparts, their free and bound phenolic compounds, which comprised gallic acid, 4-dihydroxybenzoic acid, ferulic acid, p-coumaric acid, and m-coumaric acid, were identified and quantified using high-performance liquid chromatography. Moreover, the defatting process improved thermal stability and decreased the peak viscosity of the unripe and ripe flours. The presence of starch and bioactive compounds in all the inajá flours provides a rationale for the development of new food and non-food products.


Assuntos
Arecaceae/química , Frutas/química , Antioxidantes/análise , Arecaceae/crescimento & desenvolvimento , Carotenoides/análise , Farinha/análise , Óleos Vegetais/química , Temperatura , Viscosidade
16.
Food Chem ; 331: 127180, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32544651

RESUMO

Walnut leaves are rich in phenolic components with antibiotic and antioxidative effects. However, few studies have reported the quantitative analysis of active components in walnut leaf. In this study, a novel method for quantifying the active components in walnut leaves was developed by combining ultra-high performance liquid chromatography-hybrid quadrupole-Orbitrap high-resolution mass spectrometry (UHPLC-Q-Orbitrap HRMS) with quantitative analysis of multi-components by a single marker (QAMS). In total, 13 bioactive components were analyzed by a single marker, quercetin. To evaluate the accuracy of this method, an auxiliary quantification method with 13 reference standards was established and validated. The standard method differences (SMDs) of the quantification results between QAMS and the auxiliary method were lower than 20%, indicating that the QAMS method can accurately determine the active components in walnut leaves. This method can provide a reference to address the absence of reference standards for analyzing other foods and herbs.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Juglans/química , Espectrometria de Massas/métodos , Folhas de Planta/química , Antioxidantes/análise , Limite de Detecção , Fenóis/análise , Quercetina/análise , Reprodutibilidade dos Testes
17.
Food Chem ; 329: 127157, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32504918

RESUMO

The processing and digestive stability of ethanolic extracts from four Thai rice bran varieties, namely Khao Dawk Mali 105, Hom Nil, Kiaw Ngu, and Leum Pua, were assessed by applying different thermal and pH conditions, as well as in vitro gastrointestinal digestion models. High-performance liquid chromatography, Folin-Ciocalteu analysis, as well as 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and ferric reducing antioxidant power (FRAP) assays were used to determine the chemical composition, total phenolic content (TPC), and antioxidant activity. Thermal treatment at 100 °C for 15 min induced the degradation of phenolic components and TPC, whereas the antioxidant activities measured by DPPH and FRAP assays remained stable after the heat treatment. Higher phenolic content and antioxidant activity values were observed in the extracts incubated at acidic pH levels of 3 and 5. After simulated digestion, all extracts exhibited the decrease of phenolic compounds and anthocyanin contents, as well as antioxidant activities.


Assuntos
Antocianinas/química , Antocianinas/farmacocinética , Oryza/química , Fenóis/química , Fenóis/farmacocinética , Antocianinas/análise , Antioxidantes/análise , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Digestão , Etanol/química , Calefação , Concentração de Íons de Hidrogênio , Fenóis/análise , Extratos Vegetais/química , Tailândia
18.
Arch Microbiol ; 202(8): 2233-2243, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32533206

RESUMO

Selenium nanoparticles (SeNPs) are attractive nanomaterials for application in medical diagnosis, because their toxicities are lower than the elemental selenium which is a functional element and essential for human. In the current study, SeNPs synthesis capability of a novel soil originated indigenous Bacillus isolate was investigated. In this context, effects of processing conditions (SeO2 concentration, pH, temperature, and time), and yeast extract supplementation on the synthesis of SeNPs have been tested. In addition, nanoparticles were characterized and antioxidant capacity was determined. The cell-free supernatant of the bacterium, which was obtained after the cultivation of the isolate in nutrient broth at 33 °C for 24 h, was used for the synthesis. During the synthesis color change from light yellow to red-orange was an indication of the formation of SeNPs. Effect of SeO2 concentration was tested on the formation of nanoparticles and at concentrations higher than 10 mM, there was no formation of nanoparticles. The best production was achieved at 6.4 mM concentration, at pH 9 and 33 °C in 72 h. Field emission scanning electron microscopy (FESEM) images revealed that SeNPs were spherical in shape having the diameters between 31 and 335 nm, and the average diameter was determined to be 126 nm. Energy dispersive X-ray spectroscopy analysis confirmed the presence of elemental selenium. SeNPs possessed significant antioxidant activity that the scavenging capacity was up to 56.5 ± 5% (IC50 322.8 µg/mL).


Assuntos
Bacillus/efeitos dos fármacos , Bacillus/metabolismo , Meios de Cultura/farmacologia , Nanopartículas/química , Selênio/química , Antioxidantes/análise , Microscopia Eletrônica de Varredura , Nanopartículas/ultraestrutura
19.
Food Chem ; 331: 127282, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32559597

RESUMO

Phenolics are important secondary metabolites in plants with strong antioxidant effects. Seeds germination and exogenous stimulation could activate endogenous enzymes to enhance the content of phenolic acids and flavonoids. Barley seeds geminated under NaCl (1-20 mM) treatment to evaluate the accumulation of phenolics in this study. Results showed that NaCl treatment significantly enhanced the growth of seedlings, especially bud length. NaCl treatment up-regulated genes and proteins expression of phenylalanine ammonia lyase (PAL), cinnamate-4-hydroxylase (C4H) and 4-coumarate-CoA ligase (4CL), resulting in the enhancement of their activities. As a result, phenolic acids and flavonoids contents increased by 11.19% and 32.54%, respectively, in which gallic acid, protocatechuic, fisetin, myricetin and quercetin were affected mostly. Moreover, NaCl treatment enhanced 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging capacity. Hence, NaCl stimulated the synthesis of phenolic components via enhancing gene, protein expression and the activity of key enzymes.


Assuntos
Hordeum/efeitos dos fármacos , Hordeum/metabolismo , Fenóis/metabolismo , Plântula/efeitos dos fármacos , Cloreto de Sódio/farmacologia , Antioxidantes/análise , Flavonoides/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Germinação/efeitos dos fármacos , Fenóis/análise , Fenilalanina Amônia-Liase/genética , Fenilalanina Amônia-Liase/metabolismo , Reguladores de Crescimento de Planta/farmacologia , Proteínas de Plantas/metabolismo , Plântula/metabolismo , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Transcinamato 4-Mono-Oxigenase/genética , Transcinamato 4-Mono-Oxigenase/metabolismo
20.
Food Chem ; 331: 127279, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32563800

RESUMO

Stability of protein-polyphenol aggregate particles, created by complexing polyphenols from blueberry and muscadine grape pomaces with a rice-pea protein isolate blend, was evaluated in an in vitro gastrointestinal model. Recovery index (RI; % total phenolics present post-digestion) was 69% and 62% from blueberry and muscadine grape protein-polyphenol particles, compared to 23% and 31% for the respective pomace extracts. Anthocyanins RI was 52% and 42% from particles (6% and 13% from pomace extracts), and proanthocyanidins RI was 77% and 73% from particles (25% and 14% from pomace extracts), from blueberry and grape, respectively. Protein-polyphenol particle digests retained 1.5 to 2-fold higher antioxidant capacity and suppressed the expression of pro-inflammatory cytokines, iNOS, IL6, and IL1ß, compared to unmodified extract digests, which only suppressed IL6. Protein-polyphenol particles as a delivery vehicle in foods may confer better stability during gastrointestinal transit, allow protected polyphenols to reach the gut microbiota, and preserve polyphenol bioactivity.


Assuntos
Mirtilos Azuis (Planta)/química , Polifenóis/farmacocinética , Vitis/química , Animais , Antocianinas/análise , Anti-Inflamatórios não Esteroides/farmacocinética , Antioxidantes/análise , Digestão , Indústria de Processamento de Alimentos , Frutas/química , Camundongos , Extratos Vegetais/química , Extratos Vegetais/farmacocinética , Proteínas de Vegetais Comestíveis/química , Proantocianidinas/análise , Células RAW 264.7
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