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1.
Chem Biodivers ; 19(9): e202200217, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35924460

RESUMO

In this work, phytochemical components, and the antioxidant properties of an aqueous extract obtained from a medicinal plant Hubertia ambavilla, endemic to Reunion Island, were investigated. A total of 37 compounds were detected and identified by high-performance liquid chromatography (UHPLC) using a photodiode-array detector (DAD) coupled with electrospray ionization/mass spectrometry (ESI/MSn ). From calibration curves, the quantity of secondary metabolites in the aqueous extract was calculated. The mean amounts of phenols, flavonoids, and condensed tannins found were 158.38±1.20 mg GAE/g DE, 60.41±1.65 mg AE/g DE and 23.77±1.36 mg CE/g DE, respectively. The in vitro antioxidant properties of the Hubertia ambavilla plant were measured using three methods: DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) scavenging and ferric reducing antioxidant power. The results showed that crude aqueous extract of H. ambavilla had effective radical scavenging and reducing power in comparison with standard antioxidant compounds. In conclusion, the crude extract herein presented offers a natural alternative biosource of antioxidants with potential applications in food and health industries.


Assuntos
Asteraceae , Proantocianidinas , Antioxidantes/química , Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/química , Fenóis/análise , Compostos Fitoquímicos/análise , Extratos Vegetais/química , Polifenóis/análise , Proantocianidinas/análise , Espectrometria de Massas por Ionização por Electrospray
2.
Drug Chem Toxicol ; 43(5): 539-545, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30212238

RESUMO

Strychnos pseudoquina is a plant species whose stem bark is used as bitter tonic beverage. The phytochemical analysis, as well as quantification of phenolic constituents and antioxidant activity of ethanolic extracts from S. pseudoquina stem bark, and leaves were conducted. The extracts were tested for mutagenicity (Ames test) and DNA-damaging activity (Plasmid Cleavage test). Leaves recorded the largest amount of flavonoids. The performed high-performance liquid chromatography (HPLC) showed flavonoids such as isorhamnetin and strychnobiflavone (phytochemical markers of the investigated species) in stem barks, but not in leaves. The proanthocyanidin content and antioxidant activity were significantly higher in stem barks than in leaves. Stem bark and leaf extracts presented mutagenic activity against TA98 and TA100 strains with, and without, metabolic activation (S9). The Plasmid Cleavage test did not indicate DNA-damaging activity. Our results suggest that extracts deriving from S. pseudoquina should be used with extreme caution, mainly the stem bark extract, which is widely used in folk medicine.


Assuntos
Dano ao DNA , Fenóis/análise , Casca de Planta/química , Extratos Vegetais/química , Extratos Vegetais/toxicidade , Strychnos/química , Antioxidantes/análise , Antioxidantes/farmacologia , Etanol/química , Flavonoides/análise , Testes de Mutagenicidade , Compostos Fitoquímicos/análise , Folhas de Planta/química , Caules de Planta/química , Proantocianidinas/análise , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética
3.
Biomolecules ; 9(12)2019 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-31783641

RESUMO

The search for grape varieties resistant to diseases and to climatic changes notably concerns the wine industry. Nine monovarietal wines from new red grape varieties resistant to cryptogamic diseases (downy and powdery mildews) were evaluated in terms of their total phenolic, anthocyanin and proanthocyanidin contents, anthocyanin profile, volatile composition, and sensory attributes. Thus, the question remains, will these hybrid grapes (≥97.5% of Vitisvinifera genome) lead to wines with organoleptic properties similar to those of Vitisvinifera wines that consumers are used to? Total phenolic (1547-3418 mg GA/L), anthocyanin (186-561 mg malvidin/L), and proanthocyanidin (1.4-4.5 g tannins/L) contents were in broad agreement with those previously described in the literature for monovarietal wines produced with well-known red grape varieties (Cabernet Sauvignon, Merlot, Syrah). With regard to fruity aroma, ethyl esters of straight-chain fatty acids (530-929 µg/L) stood out clearly as the major volatile components for all hybrid wines considered. Sensory analysis revealed significant differences (p < 0.05) for visual aspect, aroma, flavor, global balance, astringency, and body. Overall, these new hybrid grape varieties are not only resistant to cryptogamic diseases, but also present enough potential to become quality wines, since their phenolic and volatile attributes are close to those of common red monovarietal wines.


Assuntos
Resistência à Doença , Vitis , Vinho/análise , Antocianinas/análise , Antioxidantes/análise , Quimera , Feminino , Humanos , Masculino , Odorantes/análise , Fenóis/análise , Proantocianidinas/análise , Sensação , Volatilização
4.
J Agric Food Chem ; 67(51): 14038-14047, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31730342

RESUMO

Blackcurrants of three Finnish commercial cultivars 'Mortti', 'Ola', and 'Melalahti' cultivated in southern and northern Finland were compared on the basis of the content and composition of proanthocyanidins (PAs). Seventeen B-type PA oligomers (degree of polymerization 2-5 and 7) were detected by hydrophilic interaction liquid chromatography and electrospray ionization mass spectrometry. Total PAs, dimers, trimers, and tetramers were quantified. Among the three cultivars, 'Ola' had the highest contents of both total PAs and PA oligomers. 'Melalahti' was separated from both 'Mortti' and 'Ola' by PA profiles in the partial least-squares discriminant analysis model. All three cultivars revealed distinct responses to latitude and weather conditions. The content of total PAs showed a positive correlation to latitude in 'Ola' and 'Melalahti'. Among the meteorological variables, high temperature and radiation correlated negatively with total PAs, while only specific variables showed a correlation with PA oligomers.


Assuntos
Frutas/química , Extratos Vegetais/análise , Proantocianidinas/análise , Ribes/crescimento & desenvolvimento , Ecossistema , Finlândia , Frutas/economia , Frutas/crescimento & desenvolvimento , Extratos Vegetais/economia , Proantocianidinas/economia , Ribes/química , Temperatura
5.
Food Chem ; 242: 481-490, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29037718

RESUMO

The impact of co-fermenting white grape pomace (WP) and red grape pomace (RP) on the composition of interspecific hybrid wine was studied using the Vitis sp. 'Frontenac' and 'Vidal'. The proanthocyanidin and anthocyanin content of the resulting wines were analysed by HPLC-fluorescence and UPLC-MS/MS, respectively. The CIELAB parameters and volatile compounds were analysed using spectrophotometry-UV and GC-MS-SPME, respectively. The WP addition increased the concentration of monomeric and oligomeric flavan-3-ols, and terpenes in the wines. The manipulation of the WP/RP ratio efficiently modulated the anthocyanin profile of the wines, resulting in faded red colour, a desirable achievement in hybrid red wine, which is usually perceived as too dark. An appropriate ratio (30% RP/6% WP) improved the colour stability of the wines without a significant impact on wine colour. Addition of WP proved to be a suitable tool to modulate the colour, the phenolic and volatile composition of interspecific hybrid wine.


Assuntos
Vitis/química , Vinho/análise , Antocianinas/análise , Cromatografia Líquida de Alta Pressão , Cor , Fermentação , Cromatografia Gasosa-Espectrometria de Massas , Fenóis/análise , Polifenóis/análise , Proantocianidinas/análise , Espectrometria de Massas em Tandem
6.
J Sci Food Agric ; 97(3): 902-910, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27219821

RESUMO

BACKGROUND: Thinned fruits are agricultural by-products that contain large quantities of interesting compounds due to their early maturity stage. In this work, the phenolic profile and the antioxidant activity of six thinned stone fruits (apricot, cherry, flat peach, peach, plum and nectarine) have been investigated, focussing on proanthocyanidins. RESULTS: Thinned nectarine had the highest content of total phenols [67.43 mg gallic acid equivalents (GAE) g-1 dry weight (DW)] and total flavonoids (56.97 mg CE g-1 DW) as well as the highest antioxidant activity measured by DPPH scavenging (133.30 mg [Trolox equivalents (TE) g-1 DW] and FRAP assay (30.42 mg TE g-1 DW). Proanthocyanidins were very abundant in these by-products, and the main phenolic group quantified in cherry (10.54 mg g-1 DW), flat peach (33.47 mg g-1 DW) and nectarine (59.89 mg g-1 DW), while hydroxycinnamic acids predominate in apricot, peach and plum (6.67, 22.04 and 23.75 mg g-1 DW, respectively). The low, mean degree of polymerisation of proanthocyanidins suggests that their bioavailability could be very high. CONCLUSIONS: This study shows that thinned stone fruit extracts might be used as antioxidants in foods or as a source of compounds with health-related benefits that can be used in the pharmaceutical, cosmetic and food industries. © 2016 Society of Chemical Industry.


Assuntos
Antioxidantes/isolamento & purificação , Produção Agrícola , Produtos Agrícolas/química , Frutas/química , Resíduos Industriais/análise , Proantocianidinas/isolamento & purificação , Prunus/química , Antioxidantes/análise , Antioxidantes/química , Antioxidantes/economia , Cinamatos/análise , Cinamatos/química , Cinamatos/economia , Cinamatos/isolamento & purificação , Cosméticos/economia , Produção Agrícola/economia , Produtos Agrícolas/economia , Produtos Agrícolas/crescimento & desenvolvimento , Suplementos Nutricionais/economia , Conservantes de Alimentos/análise , Conservantes de Alimentos/química , Conservantes de Alimentos/economia , Conservantes de Alimentos/isolamento & purificação , Liofilização , Frutas/economia , Frutas/crescimento & desenvolvimento , Resíduos Industriais/economia , Estrutura Molecular , Peso Molecular , Fenóis/análise , Fenóis/química , Fenóis/economia , Fenóis/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/economia , Extratos Vegetais/isolamento & purificação , Conservantes Farmacêuticos/análise , Conservantes Farmacêuticos/química , Conservantes Farmacêuticos/economia , Conservantes Farmacêuticos/isolamento & purificação , Proantocianidinas/análise , Proantocianidinas/química , Proantocianidinas/economia , Prunus/crescimento & desenvolvimento , Prunus persica/química , Prunus persica/crescimento & desenvolvimento , Estações do Ano , Espanha
7.
Food Chem ; 208: 177-84, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27132838

RESUMO

Assessment of the flavanol composition of 41 commercial chocolates was by HPLC-DAD. Among individual flavonols ranged from 0.095 to 3.264mgg(-1), epicatechin was the predominant flavanol accounting for 32.9%. Contrary to catechin, epicatechin was a reliable predictive value of the polyphenol content. Conversely the percentage of theobromine used as a proxy measure for nonfat cocoa solids (NFCS) was not a good predictor of epicatechin or flavanol content. In a further chiral analysis, the naturally occurring forms of cocoa flavanols, (-)-epicatechin and (+)-catechin, was determined joint the occurrence of (+)-epicatechin and (-)-catechin due to the epimerization reactions produced in chocolate manufacture. (-)-Epicatechin, the most bioactive compound and predominant form accounted of 93%. However, no positive correlation was found with% cocoa solids, the most significant quality parameter.


Assuntos
Cafeína/análise , Chocolate/análise , Flavonoides/análise , Teobromina/análise , Biflavonoides/análise , Cacau/química , Catequina/análise , Cromatografia Líquida de Alta Pressão , Análise de Alimentos , Polifenóis/análise , Proantocianidinas/análise , Estereoisomerismo , Xantinas/análise
8.
Br J Nutr ; 114(3): 472-80, 2015 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-26119062

RESUMO

The scientific community continues to be interested in potential links between flavonoid intakes and beneficial health effects associated with certain chronic diseases such as CVD, some cancers and type 2 diabetes. Three separate flavonoid databases (Flavonoids, Isoflavones and Proanthocyanidins) developed by the USDA Agricultural Research Service since 1999 with frequent updates have been used to estimate dietary flavonoid intakes, and investigate their health effects. However, each of these databases contains only a limited number of foods. The USDA has constructed a new Expanded Flavonoids Database for approximately 2900 commonly consumed foods, using analytical values from their existing flavonoid databases (Flavonoid Release 3.1 and Isoflavone Release 2.0) as the foundation to calculate values for all the twenty-nine flavonoid compounds included in these two databases. Thus, the new database provides full flavonoid profiles for twenty-nine predominant dietary flavonoid compounds for every food in the database. Original analytical values in Flavonoid Release 3.1 and Isoflavone Release 2.0 for corresponding foods were retained in the newly constructed database. Proanthocyanidins are not included in the expanded database. The process of formulating the new database includes various calculation techniques. This article describes the process of populating values for the twenty-nine flavonoid compounds for every food in the dataset, along with challenges encountered and resolutions suggested. The new expanded flavonoid database released on the Nutrient Data Laboratory's website would provide uniformity in estimations of flavonoid content in foods and will be a valuable tool for epidemiological studies to assess dietary intakes.


Assuntos
Bases de Dados Factuais , Dieta , Projetos de Pesquisa Epidemiológica , Flavonoides/análise , United States Department of Agriculture , Animais , Laticínios/análise , Flavonoides/administração & dosagem , Humanos , Isoflavonas/análise , Carne/análise , Plantas Comestíveis/química , Proantocianidinas/análise , Alimentos Marinhos/análise , Estados Unidos
9.
Food Chem ; 174: 392-9, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25529697

RESUMO

Shelf life of commercial cranberry syrup irradiated with gamma radiation at a rate of 5 kGy and stored for 6 months at 25 °C and 60% relative humidity (RH) and under accelerated stability conditions was investigated. High-performance liquid chromatography coupled to electrospray ionisation quadrupole-time-of-flight mass spectrometry (HPLC-ESI-QTOF-MS) was used to characterise cranberry syrup. Afterwards, these compounds were quantified by HPLC-ESI-QTOF-MS and 4-dimethylaminocinnamaldehyde (DMAC) assay. A significant increase in the content of procyanidin B isomer 1 (from 4.4 to 7.0 µg/ml) and procyanidin A2 (from 83 to 93 µg/ml) was observed after irradiation and compared with the non-irradiated syrup. Procyanidin B isomers and prodelphinidin were stable at 25 °C during the first month of storage, whereas quercetin and some derivatives remained constant for 3 months of storage at this temperature. In short, after gamma-irradiation in dose of 5 kGy, most compounds were highly stable for a month at 25 °C.


Assuntos
Irradiação de Alimentos , Armazenamento de Alimentos , Fenóis/análise , Proantocianidinas/química , Vaccinium macrocarpon/química , Biflavonoides/análise , Catequina/análise , Cromatografia Líquida de Alta Pressão , Cinamatos/análise , Relação Dose-Resposta à Radiação , Raios gama , Limite de Detecção , Proantocianidinas/análise , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
10.
BMC Complement Altern Med ; 14: 482, 2014 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-25496367

RESUMO

BACKGROUND: The physiological effects of the non-anthocyanin fraction (NAF) in a black soybean seed coat extract on Aß-induced oxidative stress were investigated to confirm neuroprotection. In addition, we examined the preventive effect of NAF on cognitive defects induced by the intracerebroventricular (ICV) injection of Aß. METHODS: Levels of cellular oxidative stress were measured using 2',7'-dichlorofluorescein diacetate (DCF-DA). Neuronal cell viability was investigated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase (LDH) assay. To investigate in vivo anti-amnesic effects of NAF by using Y-maze and passive avoidance tests, the learning and memory impairment in mice was induced by Aß. After in vivo assays, acetylcholinesterase (AChE) activity and level of malondialdehyde (MDA) in the mouse brain were determined to confirm the cognitive effect. Individual phenolics of NAF were qualitatively analyzed by using an ultra-performance liquid chromatography (UPLC) Accurate-Mass Quadrupole Time of-Flight (Q-TOF) UPLC/MS. RESULTS: A NAF showed cell protective effects against oxidative stress-induced cytotoxicity. Intracellular ROS accumulated through Aß1-40 treatment was significantly reduced in comparison to cells only treated with Aß1-40. In MTT and LDH assay, the NAF also presented neuroprotective effects on Aß1-40-treated cytotoxicity. Finally, the administration of this NAF in mice significantly reversed the Aß1-40-induced cognitive defects in in vivo behavioral tests. After behavioral tests, the mice brains were collected in order to examine lipid peroxidation and AChE activity. AChE, preparation was inhibited by NAF in a dose-dependent manner. MDA generation in the brain homogenate of mice treated with the NAF was decreased. Q-TOF UPLC/MS analyses revealed three major phenolics from the non-anthocyanin fraction; epicatechin, procyanidin B1, and procyanidin B2. CONCLUSIONS: The results suggest that the NAF in black soybean seed coat extracts may improve the cytotoxicity of Aß in PC12 cells, possibly by reducing oxidative stress, and also have an anti-amnesic effect on the in vivo learning and memory deficits caused by Aß. Q-TOF UPLC/MS analyses showed three major phenolics; (-)-epicatechin, procyanidin B1, and procyanidin B2. Above results suggest that (-)-epicatechins are the major components, and contributors to the anti-amnesic effect of the NAF from black soybean seed coat.


Assuntos
Encéfalo/efeitos dos fármacos , Glycine max/química , Transtornos da Memória/tratamento farmacológico , Memória/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Polifenóis/farmacologia , Acetilcolinesterase/metabolismo , Peptídeos beta-Amiloides/efeitos adversos , Peptídeos beta-Amiloides/metabolismo , Animais , Antioxidantes/análise , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Biflavonoides/análise , Biflavonoides/farmacologia , Biflavonoides/uso terapêutico , Encéfalo/metabolismo , Catequina/análise , Catequina/farmacologia , Catequina/uso terapêutico , Sobrevivência Celular/efeitos dos fármacos , Transtornos Cognitivos/tratamento farmacológico , Transtornos Cognitivos/metabolismo , Aprendizagem/efeitos dos fármacos , Deficiências da Aprendizagem/tratamento farmacológico , Deficiências da Aprendizagem/metabolismo , Masculino , Transtornos da Memória/metabolismo , Camundongos Endogâmicos ICR , Fármacos Neuroprotetores/análise , Fármacos Neuroprotetores/uso terapêutico , Células PC12 , Fragmentos de Peptídeos/efeitos adversos , Fragmentos de Peptídeos/metabolismo , Fitoterapia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Polifenóis/análise , Polifenóis/uso terapêutico , Proantocianidinas/análise , Proantocianidinas/farmacologia , Proantocianidinas/uso terapêutico , Ratos , Sementes
11.
Food Chem ; 145: 883-91, 2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-24128560

RESUMO

Incorporation of ground peanut skins (PS) into peanut butter at 1.25%, 2.5%, 3.75%, and 5.0% (w/w) resulted in a marked concentration-dependent increase in both the total phenolics content (TPC) and antioxidant activity. Using dry-blanched PS to illustrate, the TPC increased by 86%, 357%, 533%, and 714%, respectively, compared to the peanut butter control devoid of PS; the total proanthocyanidins content (TPACs) rose by 633%, 1933%, 3500%, and 5033%, respectively. NP-HPLC detection confirmed that the increase in the phenolics content was attributed to the endogenous proanthocyanidins of the PS, which were characterised as dimers to nonamers by NP-HPLC/ESI-MS. FRAP values increased correspondingly by 62%, 387%, 747%, and 829%, while H-ORAC(FL) values grew by 53%, 247%, 382%, and 415%, respectively. The dietary fibre content of dry-blanched PS was ~55%, with 89-93% being insoluble fibre. Data revealed that PS addition enhances the antioxidant capacity of the peanut butter, permits a "good source of fibre" claim, and offers diversification in the market's product line.


Assuntos
Antioxidantes/análise , Arachis/química , Fibras na Dieta/análise , Manipulação de Alimentos , Alimento Funcional/análise , Fenóis/análise , Sementes/química , Antioxidantes/economia , Cromatografia Líquida de Alta Pressão , Fibras na Dieta/economia , Indústria de Processamento de Alimentos/educação , Frutas/química , Alimento Funcional/economia , Georgia , Temperatura Alta , Interações Hidrofóbicas e Hidrofílicas , Resíduos Industriais/análise , Resíduos Industriais/economia , Extratos Vegetais/análise , Proantocianidinas/análise , Rosaceae/química , Solubilidade , Espectrometria de Massas por Ionização por Electrospray , Edulcorantes/análise
12.
J Sci Food Agric ; 94(4): 736-43, 2014 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-24105894

RESUMO

BACKGROUND: Camelina sativa (CS) is an oilseed crop used for biofuel production. By-products from oil extraction are high in protein and can be used in ruminant rations; more information about their nutritive value is required also considering the antinutrional factor content of the by-products. The aim of this study was to evaluate the nutritive value of CS meal genotypes in comparison with canola. RESULTS: Ten CS genotypes and one canola cultivar were evaluated. Meals were obtained from seeds after solvent oil extraction. CS average crude protein (CP) content (g kg⁻¹ dry matter) was 457. Numerical differences in lysine and sulfur amino acid content were observed among CS genotypes. Glucosinolate (mmol kg⁻¹) content was higher for CS (23.1) than canola (7.2). Sinapine content (g kg⁻¹) was lower for CS (2.79) than for canola (4.32). Differences were observed among CS genotypes for rumen undegraded protein (RUP). Average RUP (g kg⁻¹ CP) was 316 for CS and 275 for canola. CONCLUSIONS: CS meal has potential for use in ruminant rations as a high-quality protein source. In vivo studies are needed to compare CS with other protein sources used in cattle rations. Implementation of breeding programs for improved meal quality is recommend.


Assuntos
Ração Animal/análise , Brassicaceae/química , Produtos Agrícolas/química , Proteínas Alimentares/análise , Proteínas de Plantas/análise , Ruminantes/fisiologia , Sementes/química , Ração Animal/efeitos adversos , Ração Animal/economia , Animais , Brassica napus/química , Brassica napus/genética , Brassica napus/crescimento & desenvolvimento , Brassica napus/metabolismo , Brassicaceae/genética , Brassicaceae/crescimento & desenvolvimento , Brassicaceae/metabolismo , Colina/efeitos adversos , Colina/análogos & derivados , Colina/análise , Colina/metabolismo , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/metabolismo , Fibras na Dieta/efeitos adversos , Fibras na Dieta/análise , Fibras na Dieta/economia , Fibras na Dieta/metabolismo , Proteínas Alimentares/química , Proteínas Alimentares/economia , Proteínas Alimentares/metabolismo , Digestão , Indústria de Processamento de Alimentos/economia , Variação Genética , Glucosinolatos/efeitos adversos , Glucosinolatos/análise , Glucosinolatos/metabolismo , Resíduos Industriais/análise , Resíduos Industriais/economia , Itália , Valor Nutritivo , Ácido Fítico/efeitos adversos , Ácido Fítico/análise , Ácido Fítico/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/economia , Proteínas de Plantas/metabolismo , Proantocianidinas/efeitos adversos , Proantocianidinas/análise , Proantocianidinas/metabolismo , Proteólise , Rúmen/metabolismo , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo
13.
J Sci Food Agric ; 93(2): 332-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22740383

RESUMO

BACKGROUND: Tannins added to animal diets may have a positive effect on energy and protein utilisation in the rumen. The objective of this study was to examine the impact of different sources and concentrations (20, 50, 100, 150 and 200 g kg⁻¹ dry matter (DM)) of condensed (acacia and quebracho) and hydrolysable (chestnut and valonea) tannins on rumen microbial fermentation in vitro. The experiment also included a negative control with no tannins (control) and a positive control with monensin (10 mg L⁻¹). RESULTS: In vitro gas production and total volatile fatty acid (VFA) concentration decreased as tannin concentration increased. Addition of acacia, chestnut or valonea tannins at ≥ 50 g kg⁻¹ or quebracho tannins at ≥ 100 g kg⁻¹ resulted in a decrease (up to 40%) in methane (CH4) production compared with the control. Valonea tannins were the only tannin source that reduced (-11%) CH4 production at 50 g kg⁻¹ without affecting VFA concentration. Tannin treatments reduced ammonia (NH3) and branched-chain VFA concentrations, indicating a reduction in ruminal protein degradation. Monensin reduced CH4 production (-37%) and NH3 concentration (-20%) without affecting total VFA concentration. CONCLUSION: Supplying acacia, chestnut or valonea tannins at 50 g kg⁻¹ has the potential to reduce CH4 production and ruminal protein degradation with minimum detrimental effects on efficiency of ruminal fermentation.


Assuntos
Dieta/veterinária , Digestão , Fármacos Gastrointestinais/metabolismo , Taninos Hidrolisáveis/metabolismo , Extratos Vegetais/metabolismo , Proantocianidinas/metabolismo , Rúmen/microbiologia , Acacia/química , Anacardiaceae/química , Animais , Bovinos , Dieta/efeitos adversos , Proteínas Alimentares/metabolismo , Suplementos Nutricionais/efeitos adversos , Fagaceae/química , Ácidos Graxos Voláteis/metabolismo , Feminino , Fermentação , Fármacos Gastrointestinais/efeitos adversos , Fármacos Gastrointestinais/análise , Fármacos Gastrointestinais/química , Taninos Hidrolisáveis/efeitos adversos , Taninos Hidrolisáveis/análise , Metano/antagonistas & inibidores , Metano/metabolismo , Extratos Vegetais/efeitos adversos , Extratos Vegetais/química , Proantocianidinas/efeitos adversos , Proantocianidinas/análise , Proteólise , Quercus/química , Rúmen/metabolismo
14.
Br J Nutr ; 108 Suppl 1: S91-102, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22916820

RESUMO

The present study compared the effects of feeding uncooked pea fractions (embryo v. seed coat) on glucose homeostasis in glucose-intolerant rats and examined potential mechanisms influencing glucose homeostasis. Rats were made glucose intolerant by high-fat feeding, after which diets containing both high-fat and pea fractions were fed for 4 weeks. Rats fed diets containing uncooked pea seed coats low (non-coloured seed coat; NSC) or high (coloured seed coat; CSC) in proanthocyanidins but not embryos had improved oral glucose tolerance (P < 0·05). NSC also lowered fasting and glucose-stimulated insulin secretion (P < 0·05), decreased ß-cell mass by 50 % (P < 0·05) and lowered levels of malondialdehyde, a marker of oxidative stress. Furthermore, NSC decreased the mucosal thickness of the colon by 25 % (P < 0·05), which might affect fibre fermentation and other gut functions. Small but statistically significant (P < 0·05) effects consistent with enhanced glucose transport or metabolism were observed in the skeletal muscle of rats fed NSC or CSC, for example, increased levels of AMP-dependent kinase or akt. We conclude that pea seed coats are the fraction exerting beneficial effects on glucose tolerance. Most of the changes were small in amplitude, suggesting that additive effects on multiple tissues may be important. NSC content appeared to have the most beneficial effects in improving glucose homeostasis but our ability to detect the effect of flavonoids may have been limited by their low concentration in the diet.


Assuntos
Dieta , Intolerância à Glucose/dietoterapia , Pisum sativum , Sementes , Animais , Glicemia/análise , Dieta Hiperlipídica , Fibras na Dieta/análise , Alimentos em Conserva , Glucose/metabolismo , Intolerância à Glucose/etiologia , Homeostase , Insulina/análise , Insulina/metabolismo , Células Secretoras de Insulina/química , Fígado/metabolismo , Malondialdeído/análise , Músculo Esquelético/metabolismo , Estresse Oxidativo , Proantocianidinas/administração & dosagem , Proantocianidinas/análise , Ratos , Ratos Sprague-Dawley , Sementes/química , Transdução de Sinais
15.
J Food Sci ; 77(4): M242-9, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22515250

RESUMO

UNLABELLED: Proanthocyanidins were extracted from peanut skins and investigated for their antimicrobial activity against Saccharomyces cerevisiae, Zygosaccharomyces bailii, and Zygosaccharomyces bisporus in traditional growth media (Sabouraud Dextrose and Maltose broth) and a simulated apple juice beverage. Peanut skins extracts (PSE) were prepared through a multisolvent extraction procedure. The PSE extended the lag phase growth of the 3 yeasts studied at a concentration of 1 mg/mL and at 10 mg/mL yeast growth was totally inhibited for 120 h. PSE was fractionated by normal phase high performance liquid chromatography and the active components/fractions were determined. Compounds present in the fractions were identified by liquid chromatography-mass spectrometry to determine the compounds responsible for inhibition. Fractions consisting mostly of A-type proanthocyanidin dimers, trimers, and tetramers showed the highest percent inhibition toward the yeasts tested in this study. Both optical density (OD) and standard enumeration plating methods were performed in this study. The OD method led to an overestimation of the inhibitory effects of PSE, the 2 methods agreed in respect to treatment effects but not the severity of the inhibition. PRACTICAL APPLICATION: There is a growing consumer demand for "fresh like" products containing reduced amounts of chemical preservatives without compromising food safety and quality. Therefore, the goal of this study was to determine if an extract of peanut skins containing flavonoid rich compounds could function as a natural antimicrobial in a model beverage system. Proteins were removed through the process of producing the peanut skin extract, thus it is unlikely to contain peanut allergens. The antimicrobial compounds mentioned in this study were successfully integrated into a model beverage system, and were found to have antimicrobial effect. However, the incorporation of these compounds would likely lead to negative sensory attributes at the concentration needed to achieve an appreciable antimicrobial effect alone.


Assuntos
Anti-Infecciosos/farmacologia , Arachis/química , Conservantes de Alimentos/farmacologia , Epiderme Vegetal/química , Extratos Vegetais/farmacologia , Proantocianidinas/farmacologia , Leveduras/efeitos dos fármacos , Anti-Infecciosos/análise , Anti-Infecciosos/economia , Anti-Infecciosos/isolamento & purificação , Bebidas/microbiologia , Cromatografia Líquida de Alta Pressão , Contagem de Colônia Microbiana , Conservantes de Alimentos/análise , Conservantes de Alimentos/economia , Conservantes de Alimentos/isolamento & purificação , Indústria de Processamento de Alimentos/economia , Frutas/química , Frutas/microbiologia , Resíduos Industriais/análise , Resíduos Industriais/economia , Malus/química , Malus/microbiologia , Espectrometria de Massas , Peso Molecular , Nefelometria e Turbidimetria , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Proantocianidinas/análise , Proantocianidinas/química , Proantocianidinas/isolamento & purificação , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/crescimento & desenvolvimento , Sementes/química , Leveduras/crescimento & desenvolvimento , Zygosaccharomyces/efeitos dos fármacos , Zygosaccharomyces/crescimento & desenvolvimento
16.
J Food Sci ; 77(1): C80-8, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22132766

RESUMO

UNLABELLED: Mango biowastes, obtained after processing, contain large amounts of compounds with antioxidant activity that can be reused to reduce their environmental impact. The present study evaluates the effect of solvent (methanol, ethanol, acetone, water, methanol:water [1:1], ethanol:water [1:1], and acetone:water [1:1]), and temperature (25, 50, and 75 °C) on the efficiency of the extraction of antioxidants from mango peel and seed. Among the factors optimized, extraction solvent was the most important. The solvents that best obtained extracts with high antioxidant capacity were methanol, methanol:water, ethanol:water, and acetone:water (ß-carotene test, antioxidant activity coefficient 173 to 926; thiobarbituric acid reactive substances test, inhibition ratio 15% to 89%; 2,2'-azino-bis-(3-ethylbenzothiazoline)-6-sulfonic acid ABTS(·+); and 2,2-diphenyl-1-picrylhydrazyl DPPH· scavenging, 7 to 22 and 8 to 28 g trolox equivalent antioxidant capacity [TE] per 100 g mango biowaste on a dry matter basis [DW]). Similarly, the flavonoid (0.21 to 1.4 g (+)-catechin equivalents per 100 g DW), tannin (3.8 to 14 g tannic acid equivalents per 100 g DW), and proanthocyanidin (0.23 to 7.8 g leucoanthocyanidin equivalents per 100 g DW) content was highest in the peel extracts obtained with methanol, ethanol:water, or acetone:water and in the seed extracts obtained with methanol or acetone:water. From the perspective of food security, it is advisable to choose ethanol (which also has a notable antioxidant content), ethanol:water, or acetone:water, as they are all solvents that can be used in compliance with good manufacturing practice. In general, increasing temperature improves the capacity of the extracts obtained from mango peel and seed to inhibit lipid peroxidation; however, its effect on the extraction of phytochemical compounds or on the capacity of the extracts to scavenge free radicals was negligible in comparison to that of the solvent. PRACTICAL APPLICATION: There are many antioxidant compounds in mango peel and seed, and they could be used as a natural and very inexpensive alternative to synthetic food additives. However, the conditions in which the antioxidants are extracted must be optimized. This work proves that conditions such as extraction solvent or temperature have a crucial impact on obtaining extracts rich in antioxidants from mango biowastes.


Assuntos
Antioxidantes/química , Frutas/química , Resíduos Industriais/análise , Mangifera/química , Extratos Vegetais/química , Sementes/química , Solventes/química , Acetona/química , Antioxidantes/análise , Antioxidantes/economia , Antioxidantes/isolamento & purificação , Etanol/química , Flavonoides/análise , Flavonoides/química , Flavonoides/economia , Flavonoides/isolamento & purificação , Indústria de Processamento de Alimentos/economia , Temperatura Alta , Resíduos Industriais/economia , Extratos Vegetais/economia , Extratos Vegetais/isolamento & purificação , Proantocianidinas/análise , Proantocianidinas/química , Proantocianidinas/economia , Proantocianidinas/isolamento & purificação , Taninos/análise , Taninos/química , Taninos/economia , Taninos/isolamento & purificação , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Água/química
17.
J Food Sci ; 76(1): C117-26, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21535639

RESUMO

Rice bran, a byproduct of the rice milling process, contains most of the phytochemicals. This study aimed at determining the concentrations of lipophilic, solvent-extractable (free), and cell wall-bound (bound) phytochemicals and their antioxidant capacities from brans of white, light brown, brown, purple, and red colors, and broccoli and blueberry for comparison. The concentrations of lipophilic antioxidants of vitamin E (tocopherol and tocotrienols) and γ-oryzanols were 319.67 to 443.73 and 3861.93 to 5911.12 µg/g bran dry weight (DW), respectively, and were not associated with bran color. The total phenolic, total flavonoid, and antioxidant capacities of ORAC (oxygen radical absorbance capacity), DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging, and iron-chelating in the free fraction were correlated with the intensity of bran color, while variations of these in the bound fraction were less than those in the free fraction among brans. Compounds in the bound fraction had higher antioxidant capacity of ORAC than DPPH, relative to those in the free fraction. The bound fraction of light-color brans contributed as much to its total ORAC as the free fraction. Total proanthocyanidin concentration was the highest in red rice bran, while total anthocyanin was highest in purple brans. The predominant anthocyanin was cyanidin-3-glucoside. Red and purple brans had several fold higher total phenolics and flavonoids as well as ORAC and DPPH, from both free and bound fractions, than freeze-dried blueberry and broccoli. These results indicate that rice brans are natural sources of hydrophilic and lipophilic phytochemicals for use in quality control of various food systems as well as for nutraceutical and functional food application.


Assuntos
Antioxidantes/análise , Fibras na Dieta/análise , Flavonoides/análise , Oryza/química , Fenóis/análise , Sementes/química , Antocianinas/análise , Antocianinas/química , Antocianinas/economia , Antioxidantes/química , Antioxidantes/economia , Parede Celular/química , Flavonoides/química , Flavonoides/economia , Aditivos Alimentares/análise , Aditivos Alimentares/química , Aditivos Alimentares/economia , Indústria de Processamento de Alimentos/economia , Sequestradores de Radicais Livres/análise , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/economia , Interações Hidrofóbicas e Hidrofílicas , Resíduos Industriais/análise , Resíduos Industriais/economia , Quelantes de Ferro/análise , Quelantes de Ferro/química , Quelantes de Ferro/economia , Fenóis/química , Fenóis/economia , Fenilpropionatos/análise , Fenilpropionatos/química , Fenilpropionatos/economia , Pigmentação , Polifenóis , Proantocianidinas/análise , Proantocianidinas/química , Proantocianidinas/economia , Solubilidade , Especificidade da Espécie , Vitamina E/análise , Vitamina E/química , Vitamina E/economia
18.
J Nutr ; 141(3): 447-52, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21270367

RESUMO

Proanthocyanidins (PA), the polymers of flavan-3-ols, have cardioprotective and cancer preventive properties as shown in clinical studies. The PA intake in a free-living population has not yet been reported, however. We aimed to estimate the dietary intake of PA and identify its major sources by combining the recently released and expanded USDA PA database with food consumption data of 8809 U.S. adults in the NHANES 1999-2002. U.S. adults over 19 y had a total PA intake of 95 mg/d, in the order of polymers (30%), monomers (22%), dimers (16%), 4-6 mers (15%), 7-10 mers (11%), and trimers (5%). When adjusted for energy intake, the total PA intake increased with age (P < 0.001), was higher in women than men (P < 0.01) and in alcohol consumers compared with nonconsumers (P < 0.05), and was lower in non-Hispanic blacks compared with other ethnicities (P < 0.001). Three major food sources, tea, legumes, and wines, contributed 45 mg (48%) of daily PA intake. The marked differences in PA intake among various sociodemographic subgroups need further investigation in relation to health disparities and chronic disease prevalence in the US.


Assuntos
Dieta/estatística & dados numéricos , Proantocianidinas/administração & dosagem , Proantocianidinas/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Consumo de Bebidas Alcoólicas , Bases de Dados Factuais , Dieta/etnologia , Fabaceae/química , Feminino , Análise de Alimentos , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Sementes/química , Caracteres Sexuais , Chá/química , Estados Unidos , Vinho/análise , Adulto Jovem
19.
C R Biol ; 333(9): 663-9, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20816646

RESUMO

The present study was carried out to evaluate the antioxidant activities of the root bark extract of Securidaca longepedunculata. This plant material is commonly used in folk medicine in several parts in the world. The bark extracts of S. longepedunculata were evaluated for their total phenols, flavonoids, anthocyanins, tannins content and total antioxidant capacity. The compounds were identified and quantified both by RP-HPLC and UV spectrophotometer; the antioxidant capacity was assessed by ABTS and DPPH tests and expressed as IC(50). The total phenolic compounds determinate was 9.86mg gallic acid equivalents/g dw, the total flavonoid contents was 5.85mg catechin equivalents/g dw, the total anthocyanin contents was 0.032mg cyanidin-3-glycosyl equivalents/g dw and the condensed tannins content were 1.03mg catechin equivalents/g dw. The major compound identified using RP-HPLC was quercetin (0.98mg/ml). The IC(50) value reached 5.5microg/ml, revealing that the root barks of S. longepedunculata have a very high antioxidant and anti-inflammation properties.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Antioxidantes/farmacologia , Fabaceae/química , Flavonoides/farmacologia , Fenóis/farmacologia , Casca de Planta/química , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Animais , Antocianinas/análise , Anti-Inflamatórios não Esteroides/isolamento & purificação , Antioxidantes/isolamento & purificação , Benzotiazóis , Compostos de Bifenilo , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Colorimetria , Avaliação Pré-Clínica de Medicamentos , Flavonoides/análise , Flavonoides/isolamento & purificação , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Nigéria , Óxido Nítrico/metabolismo , Fenóis/análise , Fenóis/isolamento & purificação , Picratos , Extratos Vegetais/isolamento & purificação , Polifenóis , Proantocianidinas/análise , Ácidos Sulfônicos , Tiazóis
20.
J Food Sci ; 74(6): H174-82, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19723202

RESUMO

UNLABELLED: Grape juice processing by-products, grape seed and pomace are a rich source of procyanidins, compounds that may afford protection against chronic disease. This study was undertaken to identify optimal extrusion conditions to enhance the contents of monomers and dimers at the expense of large molecular weight procyanidin oligomers and polymers in grape seed and pomace. Extrusion variables, temperature (160, 170, and 180 degrees C in grape seed, and 160, 170, 180, and 190 degrees C in pomace) and screw speed (100, 150, and 200 rpm in both) were tested using mixtures of grape seed as well as pomace with decorticated white sorghum flour at a ratio of 30 : 70 and moisture content of 45%. Samples of grape seed and pomace were analyzed for procyanidin composition before and after extrusion, and total anthocyanins were determined in pomace. Additionally, chromatograms from diol and normal phase high-performance liquid chromatography were compared for the separation of procyanidins. Extrusion of both grape by-products increased the biologically important monomer and dimers considerably across all temperature and screw speeds. Highest monomer content resulted when extruded at a temperature of 170 degrees C and screw speed of 200 rpm, which were 120% and 80% higher than the unextruded grape seed and pomace, respectively. Increases in monomer and dimer contents were apparently the result of reduced polymer contents, which declined by 27% to 54%, or enhanced extraction facilitated by disruption of the food matrix during extrusion. Extrusion processing reduced total anthocyanins in pomace by 18% to 53%. PRACTICAL APPLICATIONS: Extrusion processing can be used to increase procyanidin monomer and dimer contents in grape seed and pomace. Procyanidins in grape by-products have many health benefits, but most are present as large molecular weight compounds, which are poorly absorbed. Extrusion processing appears to be a promising technology to increase levels of the bioactive low molecular weight procyanidins.


Assuntos
Antocianinas/análise , Biflavonoides/análise , Catequina/análise , Manipulação de Alimentos/métodos , Frutas/química , Proantocianidinas/análise , Sementes/química , Vitis/química , Resíduos/análise , Antocianinas/isolamento & purificação , Biflavonoides/química , Biflavonoides/isolamento & purificação , Disponibilidade Biológica , Biopolímeros/análise , Biopolímeros/química , Catequina/química , Catequina/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Farinha , Temperatura Alta , Pressão , Proantocianidinas/química , Proantocianidinas/isolamento & purificação , Sorghum , Espectrometria de Massas por Ionização por Electrospray , Gerenciamento de Resíduos/economia , Resíduos/economia
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