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1.
J Agric Food Chem ; 72(5): 2697-2707, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38054424

RESUMO

There is a need for transformational innovation within the existing food system to achieve United Nations Sustainable Development Goal 2 of ending hunger within a sustainable agricultural system by 2030. Mycelium, the vegetative growth form of filamentous fungi, may represent a convergence of several features crucial for the development of food products that are nutritious, desirable, scalable, affordable, and environmentally sustainable. Mycelium has gained interest as technology advances demonstrate its ability to provide scalable biomass for food production delivering good flavor and quality protein, fiber, and essential micronutrients urgently needed to improve public health. We review the potential of mycelium as an environmentally sustainable food to address malnutrition and undernutrition, driven by food insecurity and caloric dense diets with less than optimal macro- and micronutrient density.


Assuntos
Promoção da Saúde , Desnutrição , Humanos , Fome , Micronutrientes , Micélio , Abastecimento de Alimentos
2.
J Agric Food Chem ; 72(20): 11617-11628, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38728580

RESUMO

When grapes are exposed to wildfire smoke, certain smoke-related volatile phenols (VPs) can be absorbed into the fruit, where they can be then converted into volatile-phenol (VP) glycosides through glycosylation. These volatile-phenol glycosides can be particularly problematic from a winemaking standpoint as they can be hydrolyzed, releasing volatile phenols, which can contribute to smoke-related off-flavors. Current methods for quantitating these volatile-phenol glycosides present several challenges, including the requirement of expensive capital equipment, limited accuracy due to the molecular complexity of the glycosides, and the utilization of harsh reagents. To address these challenges, we proposed an enzymatic hydrolysis method enabled by a tailored enzyme cocktail of novel glycosidases discovered through genome mining, and the generated VPs from VP glycosides can be quantitated by gas chromatography-mass spectrometry (GC-MS). The enzyme cocktails displayed high activities and a broad substrate scope when using commercially available VP glycosides as the substrates for testing. When evaluated in an industrially relevant matrix of Cabernet Sauvignon wine and grapes, this enzymatic cocktail consistently achieved a comparable efficacy of acid hydrolysis. The proposed method offers a simple, safe, and affordable option for smoke taint analysis.


Assuntos
Frutas , Cromatografia Gasosa-Espectrometria de Massas , Glicosídeo Hidrolases , Glicosídeos , Fenóis , Fumaça , Vitis , Hidrólise , Glicosídeos/química , Glicosídeos/metabolismo , Glicosídeos/análise , Fumaça/análise , Glicosídeo Hidrolases/metabolismo , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/genética , Fenóis/química , Fenóis/metabolismo , Vitis/química , Frutas/química , Frutas/enzimologia , Vinho/análise , Incêndios Florestais , Biocatálise
3.
J AOAC Int ; 96(4): 705-11, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24000740

RESUMO

An international collaborative study was conducted on an HPLC method with fluorescent detection for the determination of flavanols and procyanidins in chocolate and cocoa-containing materials. The sum of the oligomeric fractions with degree of polymerization 1-10 was the determined content value. Sample materials included dark and milk chocolates, cocoa powder, cocoa liquors, and cocoa extracts. The content ranged from approximately 2 to 500 mg/g (defatted basis). Thirteen laboratories--representing commercial, industrial, and academic institutions in six countries--participated in this interlaboratory study. Fourteen samples were sent as blind duplicates to the collaborators. Results for 12 laboratories yielded repeatability RSD (RSDr) values below 10% for all materials analyzed, ranging from 4.17 to 9.61%. Reproducibility RSD (RSDR) values ranged from 5.03 to 12.9% for samples containing 8.07 to 484.7 mg/g material analyzed. In one sample containing a low content of flavanols and procyanidins (approximately 2 mg/g), the RSDR was 17.68%.


Assuntos
Biflavonoides/análise , Cacau/química , Catequina/análise , Flavonoides/análise , Extratos Vegetais/análise , Proantocianidinas/análise , Cromatografia Líquida de Alta Pressão , Pós , Reprodutibilidade dos Testes
4.
J Agric Food Chem ; 71(28): 10543-10564, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37428126

RESUMO

There is an urgent requirement to minimize food waste and create more sustainable food systems that address global increases in malnutrition and hunger. The nutritional value of brewers' spent grain (BSG) makes it attractive for upcycling into value-added ingredients rich in protein and fiber having a lower environmental impact than comparable plant-based ingredients. BSG is predictably available in large quantities globally and can therefore play a role in addressing hunger in the developing world via the fortification of humanitarian food aid products. Moreover, addition of BSG-derived ingredients can improve the nutritional profile of foods commonly consumed in more developed regions, which may aid in reducing the prevalence of dietary-related disease and mortality. Challenges facing the widespread utilization of upcycled BSG ingredients include regulatory status, variability of raw material composition, and consumer perception as low-value waste products; however, the rapidly growing upcycled food market suggests increasing consumer acceptability and opportunities for significant market growth via effective new product innovation and communication strategies.


Assuntos
Desnutrição , Eliminação de Resíduos , Alimentos , Antioxidantes/análise , Dieta Vegetariana , Grão Comestível/química
5.
J AOAC Int ; 95(4): 1153-60, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22970585

RESUMO

An international collaborative study was conducted on an HPLC method with fluorescent detection (FLD) for the determination of flavanols and procyanidins in materials containing chocolate and cocoa. The sum of the oligomeric fractions with degree of polymerization 1-10 was the determined content value. Sample materials included dark and milk chocolates, cocoa powder, cocoa liquors, and cocoa extracts. The content ranged from approximately 2 to 500 mg/g (defatted basis). Thirteen laboratories representing commercial, industrial, and academic institutions in six countries participated in the study. Fourteen samples were sent as blind duplicates to the collaborators. Results from 12 laboratories yielded repeatability relative standard deviation (RSDr) values that were below 10% for all materials analyzed, ranging from 4.17 to 9.61%. The reproducibility relative standard deviation (RSD(R)) values ranged from 5.03 to 12.9% for samples containing 8.07 to 484.7 mg/g. In one sample containing a low content of flavanols and procyanidins (approximately 2 mg/g), the RSD(R) was 17.68%. Based on these results, the method is recommended for Official First Action for the determination of flavanols and procyanidins in chocolate, cocoa liquors, powder(s), and cocoa extracts.


Assuntos
Biflavonoides/análise , Cacau/metabolismo , Catequina/análise , Técnicas de Química Analítica/métodos , Técnicas de Química Analítica/normas , Cromatografia Líquida de Alta Pressão/métodos , Flavanonas/análise , Análise de Alimentos/métodos , Análise de Alimentos/normas , Proantocianidinas/análise , Cooperação Internacional , Laboratórios , Lipídeos/análise , Modelos Químicos , Polimerização , Pós/análise , Padrões de Referência , Reprodutibilidade dos Testes
6.
J Agric Food Chem ; 70(48): 15007-15027, 2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36409321

RESUMO

Research continues to provide compelling insights into potential health benefits associated with diets rich in plant-based natural products (PBNPs). Coupled with evidence from dietary intervention trials, dietary recommendations increasingly include higher intakes of PBNPs. In addition to health benefits, PBNPs can drive flavor and sensory perceptions in foods and beverages. Chardonnay marc (pomace) is a byproduct of winemaking obtained after fruit pressing that has not undergone fermentation. Recent research has revealed that PBNP diversity within Chardonnay marc has potential relevance to human health and desirable sensory attributes in food and beverage products. This review explores the potential of Chardonnay marc as a valuable new PBNP ingredient in the food system by combining health, sensory, and environmental sustainability benefits that serves as a model for development of future ingredients within a sustainable circular bioeconomy. This includes a discussion on the potential role of computational methods, including artificial intelligence (AI), in accelerating research and development required to discover and commercialize this new source of PBNPs.


Assuntos
Inteligência Artificial , Indústria Alimentícia , Humanos
7.
Front Microbiol ; 11: 393, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32318028

RESUMO

Food and human health are inextricably linked. As such, revolutionary impacts on health have been derived from advances in the production and distribution of food relating to food safety and fortification with micronutrients. During the past two decades, it has become apparent that the human microbiome has the potential to modulate health, including in ways that may be related to diet and the composition of specific foods. Despite the excitement and potential surrounding this area, the complexity of the gut microbiome, the chemical composition of food, and their interplay in situ remains a daunting task to fully understand. However, recent advances in high-throughput sequencing, metabolomics profiling, compositional analysis of food, and the emergence of electronic health records provide new sources of data that can contribute to addressing this challenge. Computational science will play an essential role in this effort as it will provide the foundation to integrate these data layers and derive insights capable of revealing and understanding the complex interactions between diet, gut microbiome, and health. Here, we review the current knowledge on diet-health-gut microbiota, relevant data sources, bioinformatics tools, machine learning capabilities, as well as the intellectual property and legislative regulatory landscape. We provide guidance on employing machine learning and data analytics, identify gaps in current methods, and describe new scenarios to be unlocked in the next few years in the context of current knowledge.

8.
Exp Biol Med (Maywood) ; 232(2): 293-300, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17259337

RESUMO

There has been considerable work on the relationships between nutrition and the immune response, particularly on studies that have focused on adaptive responses. There is increasing recognition of the importance of innate immunity in host protection and initiation of cytokine networks. In this study, we examined the effect of select cocoa flavanols and procyanidins on innate responses in vitro. Peripheral blood mono-nuclear cells (PBMCs), as well as purified monocytes and CD4 and CD8 T cells, were isolated from healthy volunteers and cultured in the presence of cocoa flavanol fractions that differ from another by the degree of flavanol polymerization: short-chain flavanol fraction (SCFF), monomers to pentamers; and long-chain flavanol fraction (LCFF), hexamers to decamers. Parallel investigations were also done with highly purified flavanol monomers and procyanidin dimers. The isolated cells were then challenged with lipopolysaccharide (LPS) with quantitation of activation using CD69 and CD83 expression and analysis of secreted tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, IL-6, IL-10, and granulocyte macrophage colony-stimulating factor (GM-CSF). The chain length of flavanol fractions had a significant effect on cytokine release from both unstimulated and LPS-stimulated PBMCs. For example, there was a striking increase of LPS-induced synthesis of IL-1beta, IL-6, IL-10, and TNF-alpha in the presence of LCFF. LCFF and SCFF, in the absence of LPS, stimulated the production of GM-CSF. In addition, LCFF and SCFF increased expression of the B cell markers CD69 and CD83. There were also unique differential responses in the mononuclear cell populations studied. We conclude that the oligomers are potent stimulators of both the innate immune system and early events in adaptive immunity.


Assuntos
Biflavonoides/farmacologia , Biopolímeros/farmacologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Cacau/química , Catequina/farmacologia , Proantocianidinas/farmacologia , Adulto , Biflavonoides/química , Biopolímeros/química , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Catequina/química , Proliferação de Células , Cromatografia Líquida de Alta Pressão , Citocinas/metabolismo , Humanos , Proantocianidinas/química
10.
J Agric Food Chem ; 54(5): 1571-6, 2006 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-16506802

RESUMO

A new chromatographic approach for separating cacao procyanidins according to their degree of polymerization has been developed. It utilizes diol stationary phase columns operating in normal phase mode with a binary gradient of acidified acetonitrile and methanol-water. Performance of the diol stationary phase was evaluated on an analytical scale utilizing classical chromatographic conditions for the normal phase separation of procyanidins according to their degree of polymerization. The new separation approach was developed on an analytical scale but further extended to the preparative scale. These newly developed analytical and preparative high-performance liquid chromatography procedures were successfully applied to the separation, as well as isolation, of cacao procyanidins from unfermented cacao seeds. The degree of polymerization associated with each molecular weight fraction was determined by mass spectrometry.


Assuntos
Cacau/química , Cromatografia Líquida de Alta Pressão/métodos , Polímeros/química , Proantocianidinas/química , Proantocianidinas/isolamento & purificação , Sementes/química , Espectrometria de Massas , Peso Molecular
11.
Am J Clin Nutr ; 81(1 Suppl): 298S-303S, 2005 01.
Artigo em Inglês | MEDLINE | ID: mdl-15640494

RESUMO

An increasing body of epidemiologic evidence supports the concept that diets rich in fruits and vegetables can promote health and attenuate, or delay, the onset of various diseases. Epidemiologic data support the idea that these health benefits are causally linked to the consumption of certain flavonoids present in fruit and vegetables. In the context of cardiovascular health, a particular group of flavonoids, namely, the flavan-3-ols (flavanols), has received attention. Flavanol-rich, plant-derived foods and beverages include wine, tea, and various fruits and berries, as well as cocoa and cocoa products. Numerous dietary intervention studies in humans and animals indicate that flavanol-rich foods and beverages might exert cardioprotective effects with respect to vascular function and platelet reactivity. This review discusses the bioactivity of flavanols in the context of cardiovascular health, with respect to their bioavailability, their antioxidant properties, and their vascular effects.


Assuntos
Antioxidantes/uso terapêutico , Cacau , Doenças Cardiovasculares/prevenção & controle , Endotélio Vascular/efeitos dos fármacos , Flavonoides/uso terapêutico , Proantocianidinas/uso terapêutico , Animais , Antioxidantes/farmacocinética , Disponibilidade Biológica , Plaquetas/efeitos dos fármacos , Doenças Cardiovasculares/etiologia , Endotélio Vascular/fisiologia , Flavonoides/farmacocinética , Frutas , Homeostase/efeitos dos fármacos , Humanos , Proantocianidinas/farmacocinética , Ratos , Verduras
13.
Free Radic Biol Med ; 34(1): 84-92, 2003 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-12498983

RESUMO

The antioxidant activity and the membrane effects of the flavanols (-)-epicatechin, (+)-catechin, and their related oligomers, the procyanidins, were evaluated in liposomes composed by phosphatidylcholine:phosphatidylserine (60:40, molar ratio). When liposomes were oxidized with a steady source of free radicals, the flavanols and procyanidins (25 microM monomer equivalents) inhibited oxidation in a manner that was related to procyanidin chain length. Flavanols and procyanidins did not influence membrane fluidity or lipid lateral phase separation. However, flavanols and procyanidins induced a decrease in the membrane surface potential and protected membranes from detergent-induced disruption. These effects were dependent on flavonoid concentration, procyanidin chain length, and membrane composition. Flavanol- and procyanidin-induced inhibition of lipid oxidation was correlated with their effect on membrane surface potential and integrity. These results indicate that the interaction of flavanols and procyanidins with phospholipid head groups, particularly with those containing hydroxyl groups, is associated with a reduced rate of membrane lipid oxidation. Thus, flavanols and procyanidins can potentially reduce oxidative modifications of membranes by restraining the access of oxidants to the bilayer and the propagation of lipid oxidation in the hydrophobic membrane matrix.


Assuntos
Biflavonoides , Catequina/farmacologia , Bicamadas Lipídicas , Lipossomos , Proantocianidinas , Cromatografia em Camada Fina , Fluidez de Membrana , Micelas
14.
Am J Clin Nutr ; 76(4): 798-804, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12324293

RESUMO

BACKGROUND: Epidemiologic studies have linked flavonoid-rich foods with a reduced risk of cardiovascular mortality. Some cocoas are flavonoid-rich and contain the monomeric flavanols (-)-epicatechin and (+)-catechin and oligomeric procyanidins formed from these monomeric units. Both the monomers and the oligomers have shown potential in favorably influencing cardiovascular health in in vitro and preliminary clinical studies. Although previous investigations have shown increasing concentrations of (-)-epicatechin in human plasma after cocoa consumption, no information is available in the published literature regarding the presence of procyanidins in human plasma. OBJECTIVE: This study sought to determine whether procyanidins can be detected and quantified in human plasma after acute consumption of a flavanol-rich cocoa. DESIGN: Peripheral blood was obtained from 5 healthy adult subjects before (baseline, 0 h) and 0.5, 2, and 6 h after consumption of 0.375 g cocoa/kg body wt as a beverage. Plasma samples were analyzed for monomers and procyanidins with the use of reversed-phase HPLC with coulometric electrochemical array detection and liquid chromatography-tandem mass spectrometry. RESULTS: Procyanidin dimer, (-)-epicatechin, and (+)-catechin were detected in the plasma of human subjects as early as 0.5 h (16 +/- 5 nmol/L, 2.61 +/- 0.46 micro mol/L, and 0.13 +/- 0.03 micro mol/L, respectively) after acute cocoa consumption and reached maximal concentrations by 2 h (41 +/- 4 nmol/L, 5.92 +/- 0.60 micro mol/L, and 0.16 +/- 0.03 micro mol/L, respectively). CONCLUSION: Dimeric procyanidins can be detected in human plasma as early as 30 min after the consumption of a flavanol-rich food such as cocoa.


Assuntos
Biflavonoides , Cacau/química , Catequina/sangue , Flavonoides/administração & dosagem , Proantocianidinas , Adulto , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Dimerização , Feminino , Flavonóis , Humanos , Cinética , Masculino , Espectrometria de Massas
15.
Thromb Res ; 106(4-5): 191-7, 2002 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-12297125

RESUMO

BACKGROUND: Flavanols modulate platelet function in vitro, but less is known of their in vivo effects and how they compare to pharmacological platelet inhibitors. We investigated the effect of a flavanol-rich cocoa beverage (897 mg/ml) in combination with and in comparison to aspirin on platelet function and activation in healthy subjects. METHODS AND RESULTS: On separate test days in a crossover design, 16 healthy adults consumed aspirin (81 mg), cocoa (as a beverage), or aspirin plus cocoa. Platelet activation was measured by surface expression of P-selectin and PAC-1 binding to the activated conformation of the GPIIb/IIIa receptor (GPIIb/IIIa-act). Platelet function was measured on an analyzer (the PFA-100) that measures shear stress-induced platelet plug formation in response to collagen-epinephrine or collagen-ADP. Plasma epicatechin concentrations peaked approximately 2 h after subjects were given either the cocoa or aspirin plus cocoa. After 6 h, cocoa inhibited epinephrine-induced platelet function. Epinephrine-induced platelet function was inhibited 2 and 6 h after aspirin, and after aspirin plus cocoa. Epinephrine-stimulated P-selectin expression was inhibited by aspirin at 6 h, and after 2 and 6 h by aspirin plus cocoa. ADP-stimulated P-selectin expression was not affected by the treatments. Cocoa and aspirin, given separately, reduced epinephrine-stimulated GPIIb/IIIa-act expression at 2 and 6 h, respectively, and at 2 and 6 h when given together, suggesting an additive effective. ASA plus cocoa inhibited ADP-stimulated GPIIb/IIIa-act expression at 6 h. CONCLUSIONS: Flavanol-rich cocoa inhibited epinephrine-stimulated platelet activation and function. These effects were qualitatively similar to aspirin, but less profound. These results emphasize the need to further examine the effects of food flavonoids for platelet modulating effects.


Assuntos
Aspirina/farmacologia , Cacau , Flavonoides/farmacologia , Ativação Plaquetária/efeitos dos fármacos , Adulto , Anticorpos Monoclonais , Testes de Coagulação Sanguínea , Catequina/sangue , Catequina/farmacocinética , Estudos Cross-Over , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/análise , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/imunologia
16.
Exp Biol Med (Maywood) ; 229(3): 255-63, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14988518

RESUMO

Flavonoids isolated from cocoa have biological activities relevant to oxidant defenses, vascular health, tumor suppression, and immune function. The intake of certain dietary flavonoids, along with other dietary substances such as tocopherols, ascorbate, and carotenoids, is epidemiologically associated with a reduced risk of cardiovascular disease. Flavonoids have also been shown to modulate tumor pathology in vitro and in animal models. We took advantage of the conserved sequences found in tyrosine kinases to study the influence of cocoa fractions and controls on gene expression. We report that the pentameric procyanidin (molecular weight of 1442 daltons) fraction isolated from cocoa was a potent inhibitor of tyrosine kinase ErbB2 expression, a receptor important in angiogenesis regulation. Consistent with this primary observation, the cocoa flavonoid fraction also suppressed human aortic endothelial cell (HAEC) growth and decreased expression of two tyrosine kinases responsive to ErbB2 modulation, namely VEGFR-2/KDR and MapK 11/p38beta2. These inhibitory effects were observed when HAECs were treated with the flavonol fraction (molecular weight 280 daltons) isolated from cocoa, which comprise the structural subunits from which the procyanidin flavonoid subclass is biosynthetically constructed. Down-regulation of ErbB2 and inhibition of HAEC growth by cocoa procyanidins may have several downstream implications, including reduced vascular endothelial growth factor (VEGF) activity and angiogenic activity associated with tumor pathology. These results suggest specific dietary flavonoids are capable of selectively inhibiting ErbB2 and therefore may offer important insight into the design of therapeutic agents that target tumors overexpressing ErbB2.


Assuntos
Antioxidantes/farmacologia , Biflavonoides , Cacau , Catequina/farmacologia , Células Endoteliais/efeitos dos fármacos , Proantocianidinas , Receptor ErbB-2/efeitos dos fármacos , Aorta/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Humanos , Proteína Quinase 11 Ativada por Mitógeno , Proteínas Quinases Ativadas por Mitógeno/biossíntese , Proteínas Quinases Ativadas por Mitógeno/efeitos dos fármacos , Extratos Vegetais/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/biossíntese , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/efeitos dos fármacos
17.
Exp Biol Med (Maywood) ; 229(8): 765-71, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15337830

RESUMO

Procyanidins extracted from cocoa play a role in the defense against oxidative stress, as well as in vascular and immune functions. We previously reported that pentameric procyanidins isolated from cocoa inhibit the expression of the tyrosine kinase ErbB2 gene, thus slowing the growth of cultured human aortic endothelial cells. We herein investigate the further consequences of such inhibition by cocoa procyanidins, particularly regarding the protein level in phosphorylation patterns and the effects on the proliferation of human dermal microvascular endothelial cells (HDMECs) following angiogenic stimulation with low-level H2O2. We report herein that both the pentameric and octameric procyanidin fractions of cocoa inhibit the proliferation of HDMECs, whereas the pentameric fraction modulates the activity of several crucial proteins in angiogenic signaling by altering their tyrosine phosphorylation. Similar to aortic endothelial cells, the pentameric procyanidin fraction down-regulates the expression of ErbB2 tyrosine kinase in HDMECs. In conclusion, we report evidence suggesting that polyphenols may influence endothelial growth signaling, thus affecting angiogenesis in vitro. If these observations are applicable in vivo, they suggest a beneficial effect for cells overexpressing ErbB2, such as in specific neoplasias


Assuntos
Biflavonoides , Cacau , Catequina/farmacologia , Divisão Celular/efeitos dos fármacos , Endotélio Vascular/citologia , Endotélio Vascular/fisiologia , Peróxido de Hidrogênio/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Proantocianidinas , Pele/irrigação sanguínea , Primers do DNA , Endotélio Vascular/efeitos dos fármacos , Flavonoides/farmacologia , Humanos , Microcirculação/fisiologia , Receptor ErbB-2/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
Life Sci ; 73(7): 857-69, 2003 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-12798412

RESUMO

Macronutrients in food and gastric acid are known to have a pronounced effect on the metabolism of many xenobiotics, an effect that impacts their efficacy as bioactive agents. In this investigation we assessed the impact of select food treatments and the histamine H(2)-receptor antagonist Famotidine (Pepcid-AC) on flavanol absorption and metabolism. Four crossover intervention studies were conducted with 6 subjects each. Volunteers consumed sugar-free, flavanol-rich cocoa (0.125 g/kg body wt) alone, with macronutrient-rich foods (8.75 or 17.5 kJ/kg subject body wt) or Famotidine (Pepcid-AC). Blood samples were drawn at 5 time points including baseline. Plasma samples were analyzed for epicatechin and catechin flavanols by HPLC. Pharmacokinetic parameters were assessed using non-compartmental methodology. When provided at 17.5 kJ/kg subject body weight (approximately 4 kcal/kg), sugar and bread test meals increased flavanol area under the curve (AUC) values to 140% of control values (P < 0.05). A corresponding tendency for plasma antioxidant capacity to increase was observed for the cocoa treatment at 1.5 and 2.5 h (P < 0.17, P < 0.06, respectively). The ability of treatment meals to affect AUC values was positively correlated with treatment carbohydrate content (r = 0.83; P< 0.02). In contrast to carbohydrate rich meals, lipid and protein rich meals and Famotidine treatment had minimal effects on flavanol absorption. Based on C(max) and AUC values, this data suggests that the uptake of flavanols can be increased significantly by concurrent carbohydrate consumption.


Assuntos
Cacau/metabolismo , Catequina/farmacocinética , Alimentos , Absorção Intestinal , Adolescente , Adulto , Área Sob a Curva , Catequina/análise , Catequina/metabolismo , Carboidratos da Dieta , Quimioterapia Combinada , Famotidina/farmacologia , Comportamento Alimentar , Feminino , Antagonistas dos Receptores H2 da Histamina/farmacologia , Humanos , Masculino , Pessoa de Meia-Idade
19.
J Agric Food Chem ; 51(3): 828-33, 2003 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-12537465

RESUMO

Cocoa flavanols and procyanidins have numerous biological activities. It is known that (-)-epicatechin, (+)-catechin, epicatechin-(4beta-8)-epicatechin (dimer B2), and epicatechin-(4beta-6)-epicatechin (dimer B5) are unstable at physiologic pH, degrading almost completely within several hours, whereas they are relatively stable at pH 5.0. The present study investigated the effects of ascorbic and citric acid on the stability of monomers and dimers in simulated intestinal juice (pH 8.5) and in sodium phosphate buffer (pH 7.4). The addition of ascorbic acid to the incubation mixture significantly increased the stability of the monomers and dimers, whereas the addition of citric acid provided no protective effects. LC-MS showed that with the degradation of dimer B2 and dimer B5, doubly linked A-type dimers were formed. The present results, although not directly transferable to in vivo conditions, suggest that ascorbic acid may stabilize cocoa flavanols and procyanidins in the intestine where the pH is neutral, or alkaline, before absorption.


Assuntos
Ácido Ascórbico/farmacologia , Biflavonoides , Cacau/química , Catequina/química , Flavonoides/química , Proantocianidinas , Líquidos Corporais , Ácido Cítrico/farmacologia , Dimerização , Estabilidade de Medicamentos , Concentração de Íons de Hidrogênio , Intestinos
20.
J Agric Food Chem ; 50(6): 1700-5, 2002 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-11879061

RESUMO

Cocoa flavanols and procyanidins possess wide-ranging biological activities. The present study investigated the stability of the cocoa monomers, (-)-epicatechin and (+)-catechin, and the dimers, epicatechin-(4beta-8)-epicatechin (Dimer B2) and epicatechin-(4beta- 6)-epicatechin (Dimer B5), in simulated gastric and intestinal juice and at different pH values. The dimers were less stable than the monomers at both acidic and alkaline pH. Incubation of Dimer B2 and Dimer B5 in simulated gastric juice (pH 1.8) or acidic pH resulted in degradation to epicatechin and isomerization to Dimer B5 and Dimer B2, respectively. When incubated in simulated intestinal juice or at alkaline pH, all four compounds degraded almost completely within several hours. These results suggest that the amount, and type, of flavanols and procyanidins in the gastrointestinal tract following the consumption of cocoa can be influenced by the stability of these compounds in both acidic and alkaline environments.


Assuntos
Cacau/química , Catequina/metabolismo , Dimerização , Líquidos Corporais/metabolismo , Catequina/química , Cromatografia Líquida de Alta Pressão , Estabilidade de Medicamentos , Suco Gástrico/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Mucosa Intestinal/metabolismo , Espectroscopia de Ressonância Magnética , Espectrometria de Massas
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