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1.
Chem Pharm Bull (Tokyo) ; 68(1): 91-95, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31902904

RESUMO

Magnolia Flower is a crude drug used for the treatment of headaches, toothaches, and nasal congestion. Here, we focused on Magnolia kobus, one of the botanical origins of Magnolia Flower, and collected the flower parts at different growth stages to compare chemical compositions and investigate potential inhibitory activities against interleukin-2 (IL-2) production in murine splenic T cells. After determining the structures, we examined the inhibitory effects of the constituents of the bud, the medicinal part of the crude drug, against IL-2 production. We first extracted the flower parts of M. kobus from the bud to fallen bloom stages and analysed the chemical compositions to identify the constituents characteristic to the buds. We found that the inhibitory activity of the buds against IL-2 production was more potent than that of the blooms. We isolated two known compounds, tiliroside (1) and syringin (2), characteristic to the buds from the methanol (MeOH) extract of Magnolia Flower. Moreover, we examined the inhibitory activities of both compounds against IL-2 production and found that tiliroside (1) but not syringin (2), showed strong inhibitory activity against IL-2 production and inhibited its mRNA expression. Thus, our strategy to examine the relationship between chemical compositions and biological activities during plant maturation could not only contribute to the scientific evaluation of medicinal parts of crude drugs but also assist in identifying biologically active constituents that have not yet been reported.


Assuntos
Interleucina-2/metabolismo , Magnolia/química , Extratos Vegetais/química , Animais , Linhagem Celular , Flavonoides/química , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Flores/química , Flores/metabolismo , Glucosídeos/química , Glucosídeos/isolamento & purificação , Glucosídeos/farmacologia , Interleucina-2/genética , Magnolia/metabolismo , Camundongos , Fenilpropionatos/química , Fenilpropionatos/isolamento & purificação , Fenilpropionatos/farmacologia , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo
2.
Sci Total Environ ; 700: 134443, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31655455

RESUMO

Worldwide, billions of people are at risk from viruses, parasites and bacteria transmitted by mosquitoes, ticks, fleas and other vectors. Over exploitation of chemical pesticides to overcome the mosquito borne diseases led to detrimental effects on environment and human health. The present research aims to explore bio-fabrication of metal silver nanomaterials using Rhazya stricta extract against deadly mosquito vectors and microbial pathogens. The phytochemical profile of the R. stricta extracts was studied by HPLC-MS and 1H NMR. Further, confirmation of the bio-fabricated silver nanoparticles (AgNPs) was carried out by UV-vis spectroscopy and characterization through FTIR, TEM, EDX, and XRD analyses. The R. stricta-fabricated AgNPs showed acute toxicity on key mosquito vectors from two different country (India and Kingdom of Saudi Arabia, KSA) strains, notably, with LC50 values of 10.57, 11.89 and 12.78 µg/ml on malarial, dengue and filarial key Indian strains of mosquito vectors, respectively, and 30.66 and 38.39 µg/ml on KSA strains of Aedes aegypti and Culex pipiens, respectively. In mosquito adulticidal activity, R. stricta extract alone exhibited LC50 values ranging from 304.34 to 382.45 µg/ml against Indian strains and from 738.733 to 886.886 against Saudi Arabian strains, while AgNPs LC50 boosted from 9.52 to 12.16 µg/ml and from 30.66 to 38.39 µg/ml, respectively. Moreover, it was noticed that at low concentration the tested AgNPs showed high growth retardation of important pathogenic bacteria such as Bacillus subtilis, Klebsiella pneumoniae and Salmonella typhi with inhibition zone diameters from 11.86 to 22.92 mm. In conclusion, the present study highlighted that R. stricta-fabricated AgNPs could be a lead material for the management of mosquito vector and microbial pathogens control.


Assuntos
Anti-Infecciosos/química , Apocynaceae , Inseticidas/química , Nanopartículas Metálicas/química , Mosquitos Vetores/efeitos dos fármacos , Extratos Vegetais/química , Prata/química , Anti-Infecciosos/toxicidade , Índia , Inseticidas/toxicidade , Dose Letal Mediana , Controle de Mosquitos/métodos , Extratos Vegetais/toxicidade
3.
Biosci Biotechnol Biochem ; 84(1): 37-42, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31578944

RESUMO

The monoterpene, trans-p-menth-3-ene-1,2,8-triol, is a naturally occurring alcohol isolated from several herbal plants. In the present work, the asymmetric synthesis of both enantiomers of this natural product was achieved using Sharpless asymmetric dihydroxylation as the key step. A reversal of enantiofacial selectivity was observed in the asymmetric dihydroxylation.


Assuntos
/química , Extratos Vegetais/química , Extratos Vegetais/síntese química , Cromatografia em Gel , Cristalização , Cromatografia Gasosa-Espectrometria de Massas , Hidrogenação , Hidroxilação , Isomerismo , Conformação Molecular , Extratos Vegetais/isolamento & purificação , Sílica Gel
4.
Biosci Biotechnol Biochem ; 84(1): 31-36, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31794330

RESUMO

4-(2-Hydroxyphenethyl)-2,6-dimethoxyphenol, a bibenzyl, was isolated from the leaves of Empetrum nigrum var. japonicum, collected from Mount Tateyama. Japanese rock ptarmigans frequently eat the leaves and fruits of this plant. The structure of the bibenzyl was confirmed by NMR spectroscopic analysis and fully characterized. A synthesis of this compound was accomplished by coupling 2-hydroxyphenylacetic acid with syringaldehyde, decarboxylation of the resultant isoaurones, and hydrogenation of the double bond in the corresponding stilbene. This compound displayed cytotoxic activity against human cancer cells (HCT116 and Hela cells) and leukemia cells (HL-60 cells). The present study suggests that this plant serves as a source of biologically active natural products. Also, our findings provide information on the secondary metabolites in the diet of Japanese rock ptarmigans.


Assuntos
Bibenzilas/síntese química , Bibenzilas/farmacologia , Ericaceae/química , Extratos Vegetais/síntese química , Extratos Vegetais/farmacologia , Bacillus subtilis/efeitos dos fármacos , Bibenzilas/química , Bibenzilas/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Células HCT116 , Células HL-60 , Células HeLa , Humanos , Japão , Espectroscopia de Ressonância Magnética , Conformação Molecular , Neoplasias/metabolismo , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Pirogalol/análogos & derivados , Pirogalol/química
5.
J Sci Food Agric ; 100(2): 500-508, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31435948

RESUMO

BACKGROUND: In the present study a metabolomics-based approach was used to discriminate among different hazelnut cultivars and to trace their geographical origins. Ultra-high-pressure liquid chromatography coupled to quadrupole-time-of-flight mass spectrometry (UHPLC-ESI/QTOF-MS) was used to profile phenolic and sterolic compounds. RESULTS: Compounds were identified against an in-house database using accurate monoisotopic mass and isotopic patterns. The screening approach was designed to discern 15 hazelnut cultivars and to discriminate among the geographical origins of six cultivars from the four main growing regions (Chile, Georgia, Italy, and Turkey). This approach allowed more than 1000 polyphenols and sterols to be annotated. The metabolomics data were elaborated with both unsupervised (hierarchical clustering) and supervised (orthogonal projections to latent structures discriminant analysis, OPLS-DA) statistics. These multivariate statistical tools allowed hazelnut samples to be discriminated, considering both 'cultivar type' and 'geographical origin'. Flavonoids (anthocyanins, flavanols and flavonols - VIP scores 1.34-1.49), phenolic acids (mainly hydroxycinnamics - VIP scores 1.35-1.55) together with cholesterol, ergosterol, and stigmasterol derivatives (VIP scores 1.34-1.49) were the best markers to discriminate samples according to geographical origin. CONCLUSIONS: This work illustrates the potential of untargeted profiling of phenolics and sterols based on UHPLC-ESI/QTOF mass spectrometry to discriminate hazelnut and support authenticity and origin. © 2019 Society of Chemical Industry.


Assuntos
Corylus/química , Nozes/química , Extratos Vegetais/química , Chile , Cromatografia Líquida de Alta Pressão , Corylus/classificação , Corylus/metabolismo , Análise Discriminante , República da Geórgia , Itália , Espectrometria de Massas , Metabolômica , Análise Multivariada , Nozes/classificação , Nozes/metabolismo , Fenóis/química , Fenóis/metabolismo , Extratos Vegetais/metabolismo , Esteróis/química , Esteróis/metabolismo , Turquia
6.
J Sci Food Agric ; 100(2): 509-516, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31487036

RESUMO

BACKGROUND: Emblica officinalis, known as amla in Ayurveda, has been used as a folk medicine to treat numerous pathological conditions, including diabetes. However, the novel extract of E. officinalis fruit extract (amla fruit extract, AFE, Saberry®) containing 100 g kg-1 ß-glucogallin along with hydrolyzable tannins has not yet been extensively studied for its antidiabetic potential. OBJECTIVE: The aim of this study was to investigate the antidiabetic and antioxidant activities of AFE and its stability during gastric stress as well as its thermostability. METHODS: The effect of AFE on the inhibition of pancreatic α-amylase and salivary α-amylase enzymes was studied using starch and yeast α-glucosidase enzyme using 4-nitrophenyl α-d-glucopyranoside as substrate. Further, 2,2-diphenyl-1-picrylhydrazyl radical scavenging and reactive oxygen species inhibition assay was performed against AFE. RESULTS: AFE potently inhibited the activities of α-amylase and α-glucosidase in a concentration-dependent manner with half maximal inhibitory concentration (IC50 ) values of 135.70 µg mL-1 and 106.70 µg mL-1 respectively. Furthermore, it also showed inhibition of α-glucosidase (IC50 562.9 µg mL-1 ) and dipeptidyl peptidase-4 (DPP-4; IC50 3770 µg mL-1 ) enzyme activities. AFE is a potent antioxidant showing a free radical scavenging activity (IC50 2.37 µg mL-1 ) and protecting against cellular reactive oxygen species (IC50 1.77 µg mL-1 ), and the effects elicited could be attributed to its phytoconstituents. CONCLUSION: AFE showed significant gastric acid resistance and was also found to be thermostable against wet heat. Excellent α-amylase, α-glucosidase, and DPP-4 inhibitory activities of AFE, as well as antioxidant activities, strongly recommend its use for the management of type 2 diabetes mellitus. © 2019 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Antioxidantes/química , Inibidores da Dipeptidil Peptidase IV/química , Frutas/química , Inibidores de Glicosídeo Hidrolases/química , Phyllanthus emblica/química , Extratos Vegetais/química , Antioxidantes/isolamento & purificação , Diabetes Mellitus Tipo 2/enzimologia , Dipeptidil Peptidase 4/química , Inibidores da Dipeptidil Peptidase IV/isolamento & purificação , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Humanos , Hipoglicemiantes/química , Hipoglicemiantes/isolamento & purificação , Extratos Vegetais/isolamento & purificação , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/química , alfa-Glucosidases/química
7.
J Sci Food Agric ; 100(1): 201-211, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31487402

RESUMO

BACKGROUND: The sunflower oil industry produces a large amount of waste that is not currently commercially exploited, as in the case of oil-tank settlings. The recovery of a high value-added by-product, such as sunflower wax, would increase the commercial value of this waste. In this original research paper, a method that allows the recovery and purification of this by-product was developed. The wax was characterized and its potential use as an organogelator agent was investigated. RESULTS: The waste sample was composed of 45.1% oily material, 16.9% of this being impure waxes. Purification was performed through two different methods, obtaining three waxes with different degrees of purity. All the waxes were composed of wax esters with a range of 40-60 carbon atoms, exhibiting traces of carotenes, free fatty acids, and free fatty alcohols. The presence of phospholipids was observed in two of them. The third wax presented a higher total wax ester content and physicochemical characteristics (color and thermal behavior) similar to those of commercial sunflower waxes, and was the most efficient organogelator agent, requiring only a small amount of wax (1.5%) to structure high oleic sunflower oil. CONCLUSION: It was verified that sunflower wax could be recovered from oil-tank settlings. A purification method that allowed sunflower wax with similar physicochemical properties to those of commercial waxes to be obtained was also developed. The purified waxes were capable of structuring high oleic sunflower oil. © 2019 Society of Chemical Industry.


Assuntos
Helianthus/química , Extratos Vegetais/isolamento & purificação , Resíduos/análise , Ceras/isolamento & purificação , Fracionamento Químico , Ésteres/química , Ésteres/isolamento & purificação , Ácidos Graxos/química , Ácidos Graxos/isolamento & purificação , Extratos Vegetais/química , Óleo de Girassol/química , Ceras/química
8.
J Sci Food Agric ; 100(1): 258-267, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31512250

RESUMO

BACKGROUND: Composite gels were individually prepared from 20 g kg-1 myofibrillar protein (MP) imbedded with typical native starch (potato, tapioca, rice or corn starch) in 0.6 mol L-1 NaCl at pH 6.2. The gel strength, water holding capacity, rheological properties and microstructure of the obtained myofibrillar protein-starch composite gels were evaluated. RESULTS: Tapioca starch improved (P < 0.05) gel strength and water holding capacity of MP composite gel at 80 °C. Rheological properties of MP-starch composites differed significantly with the addition of different types of native starch. Additionally, the promoting effect of starch on the storage modulus of the composite gels positively correlated with the gelatinization properties of different typical starch. Environmental scanning electron microscopy showed that the filling effect of starch on the composite gel was related to the pasting temperature and particle size of typical starch, with almost no particles forming at 80 °C. Moreover, the addition of starch changed the relaxation peak area and increased the relaxation time in nuclear magnetic resonance tests, which suggested that starch could improve the water holding capacity of MP-starch composite gels. CONCLUSION: Different typical native starch has varied impacts on the gel strength, water holding capacity, rheological properties and microstructure of MP gels, indicating the potential and feasibility of these typical native starches as an addition agent to modify the textural properties in comminuted meat products. © 2019 Society of Chemical Industry.


Assuntos
Produtos da Carne/análise , Proteínas Musculares/química , Miofibrilas/química , Extratos Vegetais/química , Amido/química , Animais , Aditivos Alimentares/química , Géis/química , Espectroscopia de Ressonância Magnética , Manihot/química , Oryza/química , Reologia , Solanum tuberosum/química , Suínos , Zea mays/química
9.
J Sci Food Agric ; 100(2): 682-694, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31583702

RESUMO

BACKGROUND: Cropping practices focusing on agronomic water use efficiency and their impact on quality parameters must be investigated to overcome constraints affecting olive groves. We evaluated the response of olive trees (Olea europaea, cv. 'Cobrançosa') to different water regimes: full irrigation (FI, 100% crop evapotranspiration (ETc )), and three deficit irrigation strategies (DIS) (regulated (RDI, irrigated with 80% of crop evapotranspiration (ETc ) in phases I and III of fruit growth and 10% of ETc in the pit hardening stage), and two continuous sustained strategies (SDI) - a conventional SDI (27.5% of ETc ), and low-frequency irrigation adopted by the farmer (SDIAF, 21.2% of ETc ). RESULTS: The effects of water regimes on the plant water status, photosynthetic performance, metabolite fluctuations and fruit quality parameters were evaluated. All DIS treatments enhanced leaf tissue density; RDI and SDI generally did not affect leaf water status and maintained photosynthetic machinery working properly, and the SDIAF treatment impaired olive tree physiological indicators. The DIS treatments maintained the levels of primary metabolites in leaves, but SDIAF plants showed signs of oxidative stress. Moreover, DIS treatments led to changes in the secondary metabolism, both in leaves and in fruits, with increased total phenolic compounds, ortho-diphenols, and flavonoid concentration, and higher total antioxidant capacity, as well higher oil content. Phenolic profiles showed the relevance of an early harvest in order to obtain higher oleuropein levels with associated higher health benefits. CONCLUSION: Adequate DIS are essential for sustainable olive growing, as they enhance the competitiveness of the sector in terms of olive production and associated quality parameters. © 2019 Society of Chemical Industry.


Assuntos
Irrigação Agrícola/métodos , Frutas/química , Olea/crescimento & desenvolvimento , Extratos Vegetais/química , Água/metabolismo , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Olea/química , Olea/metabolismo , Estresse Oxidativo , Fenóis/química , Fenóis/metabolismo , Fotossíntese , Extratos Vegetais/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Água/análise
10.
J Sci Food Agric ; 100(1): 343-353, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31584698

RESUMO

BACKGROUND: Herbs are rich in various beneficial bioactive compounds and they can be used for many different purposes. One of the most common is maceration of herbs in alcohol. Different substances respond differently to extraction in prepared solutions. It is very important to enhance the highest proportion of beneficial ingredients during the maceration process in a herbal liqueur. A comparative analysis of numerous different phenolic compounds from eight of the most frequently used herbs for making aperitifs in Europe was performed. RESULTS: In the comparison among all studied herbs, the highest phenolic content was found with Artemisia absinthium (wormwood) (14.61 mg g-1 ) and Mentha piperita (peppermint) (13.89 mg g-1 ), while the lowest content was found with Centaurium erythraea (common centaury) (3.96 mg g-1 ). Salvianolic acid isomers and caffeic acid derivatives were the greatest contributors to the total phenolic content in lemon balm, wormwood, peppermint, fennel and sage. These compounds contain more hydroxyl groups and they were better extracted at the beginning of the maceration process. Caraway and common centaury contain more flavonols (quercetin and kaempferol derivatives), with higher chemical stability and fewer hydroxyl groups in their structure. CONCLUSION: The compositions of eight herbal liqueurs were highly related to the presence of different herbal ingredients and their solubility in the extract over time. Most flavonol derivatives were extracted over a longer time and the two liqueurs (common centaury and caraway) therefore had the highest phenolic contents after 3 weeks of maceration. © 2019 Society of Chemical Industry.


Assuntos
Bebidas Alcoólicas/análise , Extratos Vegetais/química , Plantas Medicinais/química , Artemisia/química , Carum/química , Centaurium/química , Europa (Continente) , Manipulação de Alimentos , Isomerismo , Mentha piperita/química , Fenóis/química
11.
J Sci Food Agric ; 100(2): 578-586, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31591732

RESUMO

BACKGROUND: Canola oil processing generates as by-products cakes rich in proteins, which have high nutritional value. These cakes contain an expressive amount of phenolic compounds which are important as antioxidants, but can interfere in proteins nutritional value. The aim of this work was to identify the phenolic compounds present in canola seed cake and to maximize their extraction by investigating the factors: temperature (20-70 °C), ethanol concentration in water (0-85%) and sample/solvent ratio (1:5-1:20). RESULTS: The maximum phenolic compounds amount was obtained at 65 °C, ethanol concentration of 35% and sample/solvent ratio of 1:20. At this condition, more than 95% of these compounds were extracted from the canola seed cake. It was observed that the solvent could be re-used for additional extractions, reducing the solvent consumption. A large number of phenolic compounds were identified (24 compounds) and quantified, including sinapic acid derivatives, flavonoid glycosides derivatives and major and minor sinapoyl choline derivatives. CONCLUSION: The phenolic compounds can be easily extracted from the canola seed cake, resulting in a cake with low antinutrients content and, in contrast, an extract rich in antioxidant compounds with possible use as a natural source of antioxidants. © 2019 Society of Chemical Industry.


Assuntos
Antioxidantes/química , Brassica napus/química , Fenóis/química , Extratos Vegetais/química , Antioxidantes/isolamento & purificação , Espectrometria de Massas , Valor Nutritivo , Fenóis/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Sementes/química
12.
J Sci Food Agric ; 100(1): 376-383, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31595514

RESUMO

BACKGROUND: Every year, the viticulture activity generates considerable amounts of underused lignocellulosic residues as grape cane, which are generally composted or burned despite their potential value as a source of bioactive compounds. Determination of their phytochemical composition and total antioxidant capacity (TAC) may be a useful way of exploiting different high-added value applications. RESULTS: Twenty-one phenolic compounds (PC) and two carotenoids (Car) were quantified by high performance-liquid chromatography-diode array detection in eight grape varieties from different locations in Mendoza, Argentina. The maximum concentrations corresponded to the stilbene ϵ-viniferin [10 552 µg g-1 dry weight (DW)], followed by the flavanols (+)-catechin (3718 µg g-1 DW) and (-)-epicatechin (2486 µg g-1 DW). In addition, lutein and ß-carotene were quantified at levels ranging between 350 and 2400 ng g-1 DW. The TAC of the extracts was assessed by oxygen radical absorbance capacity, 2,20-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid and 1,1-diphenyl-2-picrylhydrazyl assays, with a good correlation between TAC and total PC for each sample (r ≥ 0.82). CONCLUSION: Samples of cv. Malbec, the most representative variety of Argentina's winemaking industry, presented high contents of PC, particularly ϵ-viniferin, (+)-catechin and (-)-epicatechin. Quercetin-3-galactoside, OH-tyrosol and Car were reported for the first time in grape canes of the eight varieties. The results add to the existing knowledge related to this inexpensive source of high-value bioactive compounds, which could be used as functional ingredients. © 2019 Society of Chemical Industry.


Assuntos
Antioxidantes/química , Extratos Vegetais/química , Polifenóis/química , Vitis/química , Resíduos/análise , Cromatografia Líquida de Alta Pressão , Compostos Fitoquímicos/química , Caules de Planta/química , Vitis/classificação
13.
J Sci Food Agric ; 100(2): 614-622, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31597198

RESUMO

BACKGROUND: Lonicera japonica Thunb is a common herb in East Asia. The flower buds are usually regarded as the traditional medicinal part, while leaves and stems are considered less valuable and receive little attention. This study compared the chemical constituents and anti-inflammatory effects of the different tissues in L. japonica Thunb for the first time. RESULTS: Thirty compounds were identified by ultra-performance liquid chromatography-photodiode detector-quadrupole / time of flight-mass spectrometry (UPLC-PDA-Q/TOF-MS/MS) analysis. Hydroxycinnamic acids, flavonoids, and iridoids were identified as the major components. The flower buds (FLJ), leaves (LLJ), and stems (SLJ) of L. japonica Thunb showed strong similarities in chemical components. The LLJ contained higher levels of hydroxycinnamic acids and flavonoids than the FLJ and SLJ. Furthermore, FLJ, LLJ, and SLJ exhibited potent anti-inflammatory activity in croton oil-induced ear edema and carrageenan-induced paw edema assays in mice. Moreover, FLJ, LLJ, and SLJ showed a cytoprotective effect on lipopolysaccharide- (LPS-) stimulated RAW 264.7 macrophages. Lipopolysaccharide-induced increases in nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and interleukin-6 (IL-6) were suppressed by treatments of FLJ, LLJ, and SLJ, respectively. The LLJ possessed a stronger anti-inflammatory effect than the FLJ. CONCLUSION: Leaves and stems of L. japonica Thunb have chemical components and anti-inflammatory properties similar to flower buds, and may become alternative or supplementary sources of flower buds. © 2019 Society of Chemical Industry.


Assuntos
Anti-Inflamatórios/química , Edema/tratamento farmacológico , Lonicera/química , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Animais , Anti-Inflamatórios/administração & dosagem , Carragenina/efeitos adversos , Cromatografia Líquida de Alta Pressão , Edema/induzido quimicamente , Edema/genética , Edema/imunologia , Flavonoides/administração & dosagem , Flavonoides/química , Flores/química , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Interleucina-6/genética , Interleucina-6/imunologia , Camundongos , Folhas de Planta/química , Caules de Planta/química , Espectrometria de Massas em Tandem , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
14.
J Agric Food Chem ; 68(2): 591-602, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31859496

RESUMO

An ultrahigh performance liquid chromatography-electrospray-tandem mass spectrometry method was developed for the determination of 36 phenolic compounds in paprika. The proposed method showed good method performance with limits of quantitation between 0.03 and 50 µg/L for 16 compounds and between 50 µg/L and 1 mg/L for 12 compounds. Good linearity (R2 > 0.995), run-to-run and day-to-day precisions (%RSD values < 12.3 and < 19.2%, respectively), and trueness (relative errors < 15.0%) were obtained. The proposed method was applied to the analysis of 111 paprika samples from different production regions: Spain (La Vera PDO and Murcia PDO) and Czech Republic, each one including different flavor varieties (sweet, bittersweet, and spicy). Phenolic profiles and concentration levels showed to be good chemical descriptors to achieve paprika classification and authentication according to the production region by principal component analysis and partial least squares regression-discriminant analysis. In addition, perfect classification among flavor varieties for Murcia PDO and Czech Republic samples was also obtained.


Assuntos
Capsicum/química , Contaminação de Alimentos/análise , Fenóis/química , Extratos Vegetais/química , Cromatografia Líquida de Alta Pressão , República Tcheca , Análise de Componente Principal , Espanha , Especiarias/análise , Espectrometria de Massas em Tandem
15.
Food Chem ; 308: 125592, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31648086

RESUMO

This paper investigated the conformational and functional properties of myofibrillar protein modified by five phenolic compounds, including cyanidin 3-O-glucoside, cyanidin 3-O-rutinoside, caffeic acid, quercetin and rutin, dominantly presented in mulberry polyphenols-enriched sausage. These phenolic compounds significantly affected the structure of myofibrillar protein as indicated by the remarkable losses of carbonyl and ε-NH2 and the obviously fluorescence quenching effect (P < 0.05). Modified myofibrillar protein increased antioxidative activity but decreased thermal stability. Myofibirllar protein modified with rutin had no change in thermal stability but improved emulsifying properties. Quercetin has little effect on secondary structure of myofibirlliar protein. Caffeic acid triggered the conversion of α-helix to ß-sheet in myofibrillar protein, and the resulted protein exhibited the strongest fluorescence quenching, solubility and antioxidant activity among all samples. Overall, the results suggested that all phenolic compounds involved in the changes of meat product quality, with caffeic acid and rutin being the most critical ones.


Assuntos
Morus/química , Extratos Vegetais/química , Polifenóis/química , Proteínas/química , Frutas/química , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína
16.
Food Chem ; 308: 125571, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31655480

RESUMO

Grape seed maturation involves the gradual oxidation of tannins, decreasing excessive bitterness and astringency in wine. In cool climates, this process is limited by the short growing season, affecting wine quality. A "freeze-thaw" treatment on seeds of red vinifera cultivars at veraison and harvest was used to evaluate the effect of oxidation and extractability on seed phenolic fractions. Freezing increased the extraction of total phenolics and o-diphenols quantified from fractionation (fraction 1, vacuolar tannins; fraction 2, hydrogen bonded tannins; fraction 3, covalently bonded tannins), especially at harvest. Despite this, colorimetry, microscopy, oxidation reactivity index (ORI), and correlations between the color index and fractions indicated that freezing disrupted vacuole integrity, enhancing oxidation in the seed coat. In conclusion, vacuolar tannins (which are the main seed phenolics extracted during fermentation) were highly correlated with seed color change, potentially providing information for winemaking in cool climate regions.


Assuntos
Extratos Vegetais/química , Taninos/isolamento & purificação , Vitis/química , Vinho/análise , Clima , Fermentação , Congelamento , Oxirredução , Fenóis/química , Sementes/química
17.
Food Chem ; 307: 125524, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31639581

RESUMO

Methylcellulose (MC) polymer was used to prepare the edible films. Then, the Rheum ribes L. ethanol extract (RE) was added to the films in order to act as a natural antimicrobial agent. All the methylcellulose films were characterized for bioactivity and the physicochemical analysis were carried out to define functional group interactions between the polymer and RE. The strongest antimicrobial effect was obtained with MC films enriched with 2% (w/w) RE against to Listeria monocytogenes with 20.3 ±â€¯2.5 mm zone diameter. In the presence of RE, the tensile strength of film decreased, whereas the extract concentration significantly increased. The elongation at break and the water vapor permeability (WVP) values of the films were found to have decreased significantly in parallel with the increase in RE content. Moreover, the increase in the concentration of RE caused an increment in the hydrophilic properties, especially contact angle values of the films.


Assuntos
Metilcelulose/química , Extratos Vegetais/química , Rheum/química , Antioxidantes/química , Interações Hidrofóbicas e Hidrofílicas , Listeria monocytogenes/efeitos dos fármacos , Permeabilidade , Extratos Vegetais/farmacologia , Rheum/metabolismo , Resistência à Tração , Água/química
18.
Food Chem ; 307: 125515, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31648177

RESUMO

This study evaluated the polyphenol profile and the antioxidative properties of Plinia trunciflora (O. Berg) Kausel fruits. Folin-Ciocalteau and pH-jumping methods indicated that these berries are a major source of antioxidant polyphenols (1201.05 mg GAE/100 g FW), particularly anthocyanins. HPLC-DAD-ESI-MS/MS analysis identified cyanidine glycosides as the main components. Flavon-3-ols and hydrolysable-tannins were also found. CAA assay showed that extracts of P. trunciflora fruits prevent lipid peroxidation in HepG2 cells with higher efficacy than other colourful fruits (CAA50 935.25 mg FW/mL cell medium). Moreover, our results suggested that the observed antioxidant protection involve both redox active properties of P. trunciflora components, as measured by ABTS, DPPH and FRAP assays, and upregulation of the genes coding for the antioxidant enzymes MnSOD and GPx, as evaluated by qRT-PCR. Collectively, our data provided evidence on the potential of P. trunciflora fruit as a very rich source of natural antioxidant molecules.


Assuntos
Antioxidantes/metabolismo , Suplementos Nutricionais/análise , Myrtaceae/química , Compostos Fitoquímicos/química , Cromatografia Líquida de Alta Pressão , Frutas/química , Frutas/metabolismo , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Células Hep G2 , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Myrtaceae/metabolismo , Compostos Fitoquímicos/análise , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Polifenóis/análise , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Espectrometria de Massas em Tandem , Regulação para Cima/efeitos dos fármacos
19.
Food Chem ; 307: 125528, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31648181

RESUMO

Simple, rapid, convenient, and economical surface enhanced Raman scattering (SERS) substrate is developed for on-site evaluation of Aflatoxin B1 (AFB1) in food matrix using handheld Raman Spectrometer. Self-assembly of gold nanobipyramids (Au NBPs) into the nanoholes of anodic aluminum oxide (AAO) template/pattern using 'drop-dry' approach provides a reliable pathway for the rapid fabrication of highly active and uniform SERS substrate. It shows enhanced and reproducible SERS signals towards the probe molecule, 4-aminothiophenol (4-ATP) with a relative standard deviation (RSD) of less than 10% and an average enhancement factor (EF) of 1 × 108. For practical application, the proposed method is demonstrated for the detection of aflatoxin B1 (AFB1) in peanut extracts. The results show that the AFB1 in peanut extracts can be identified within 1 min, with a limit of detection of 0.5 µg/L. Compared with conventional ELISA based AFB1 analysis, our method is much more efficient (1 min versus >30 min).


Assuntos
Aflatoxina B1/análise , Arachis/química , Nanoestruturas/química , Extratos Vegetais/química , Análise Espectral Raman/métodos , Óxido de Alumínio/química , Arachis/metabolismo , Ouro/química , Limite de Detecção
20.
Food Chem ; 308: 125633, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31644968

RESUMO

The objective of this study was to evaluate the in vitro antimicrobial and antioxidant activities of different bran extracts and concentrations, and their influence on the parameters of a mayonnaise-type emulsion. To that end, first ethanol and then water were used to extract two rice bran extracts (RBE) from rice bran. Both these extracts were then added at two different concentrations (0.5 and 2%) to the emulsions that were subsequently analysed after seven days under two different storage temperatures, 4 °C and 20 °C. The antioxidant and antimicrobial ability of the extracts were evaluated, along with a control and a synthetic antioxidant. Results indicate the positive effect of rice bran extracts as additives in the food matrix. Ethanolic rice bran extract (EE) at 2% decreased the oxidation as well as mould and yeast proliferation and preserved the emulsion structure, while the other treatments acted in a similar way although their effect was less pronounced.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Oryza/química , Extratos Vegetais/farmacologia , Antibacterianos/química , Antioxidantes/química , Condimentos , Emulsões , Escherichia coli/efeitos dos fármacos , Listeria/efeitos dos fármacos , Oxirredução , Extratos Vegetais/química
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