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1.
Proc Natl Acad Sci U S A ; 114(30): E6260-E6269, 2017 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-28696284

RESUMO

Caffeine, generally known as a stimulant of gastric acid secretion (GAS), is a bitter-tasting compound that activates several taste type 2 bitter receptors (TAS2Rs). TAS2Rs are expressed in the mouth and in several extraoral sites, e.g., in the gastrointestinal tract, in which their functional role still needs to be clarified. We hypothesized that caffeine evokes effects on GAS by activation of oral and gastric TAS2Rs and demonstrate that caffeine, when administered encapsulated, stimulates GAS, whereas oral administration of a caffeine solution delays GAS in healthy human subjects. Correlation analysis of data obtained from ingestion of the caffeine solution revealed an association between the magnitude of the GAS response and the perceived bitterness, suggesting a functional role of oral TAS2Rs in GAS. Expression of TAS2Rs, including cognate TAS2Rs for caffeine, was shown in human gastric epithelial cells of the corpus/fundus and in HGT-1 cells, a model for the study of GAS. In HGT-1 cells, various bitter compounds as well as caffeine stimulated proton secretion, whereby the caffeine-evoked effect was (i) shown to depend on one of its cognate receptor, TAS2R43, and adenylyl cyclase; and (ii) reduced by homoeriodictyol (HED), a known inhibitor of caffeine's bitter taste. This inhibitory effect of HED on caffeine-induced GAS was verified in healthy human subjects. These findings (i) demonstrate that bitter taste receptors in the stomach and the oral cavity are involved in the regulation of GAS and (ii) suggest that bitter tastants and bitter-masking compounds could be potentially useful therapeutics to regulate gastric pH.


Assuntos
Cafeína/farmacologia , Ácido Gástrico/metabolismo , Células Parietais Gástricas/fisiologia , Flavonas/farmacologia , Humanos , Células Parietais Gástricas/metabolismo , Receptores Acoplados a Proteínas G/fisiologia , Paladar
2.
J Cell Biochem ; 116(6): 1153-63, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25704235

RESUMO

Red pepper and its major pungent principle, capsaicin (CAP), have been shown to be effective anti-obesity agents by reducing energy intake, enhancing energy metabolism, decreasing serum triacylglycerol content, and inhibiting adipogenesis via activation of the transient receptor potential cation channel subfamily V member 1 (TRPV1). However, the binding of CAP to the TRPV1 receptor is also responsible for its pungent sensation, strongly limiting its dietary intake. Here, the effects of a less pungent structural CAP-analog, nonivamide, on adipogenesis and underlying mechanisms in 3T3-L1 cells were studied. Nonivamide was found to reduce mean lipid accumulation, a marker of adipogenesis, to a similar extent as CAP, up to 10.4% (P < 0.001). Blockage of the TRPV1 receptor with the specific inhibitor trans-tert-butylcyclohexanol revealed that the anti-adipogenic activity of nonivamide depends, as with CAP, on TRPV1 receptor activation. In addition, in cells treated with nonivamide during adipogenesis, protein levels of the pro-adipogenic transcription factor peroxisome-proliferator activated receptor γ (PPARγ) decreased. Results from miRNA microarrays and digital droplet PCR analysis demonstrated an increase in the expression of the miRNA mmu-let-7d-5p, which has been associated with decreased PPARγ levels.


Assuntos
Adipogenia/efeitos dos fármacos , Capsaicina/análogos & derivados , MicroRNAs/metabolismo , PPAR gama/metabolismo , Células 3T3-L1 , Animais , Capsaicina/farmacologia , Camundongos , Canais de Cátion TRPV/metabolismo
3.
Angew Chem Int Ed Engl ; 53(5): 1439-42, 2014 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-24459060

RESUMO

Flavonoids are a large group of plant secondary metabolites with a variety of biological properties and are therefore of interest to many scientists, as they can lead to industrially interesting intermediates. The anaerobic gut bacterium Eubacterium ramulus can catabolize flavonoids, but until now, the pathway has not been experimentally confirmed. In the present work, a chalcone isomerase (CHI) and an enoate reductase (ERED) could be identified through whole genome sequencing and gene motif search. These two enzymes were successfully cloned and expressed in Escherichia coli in their active form, even under aerobic conditions. The catabolic pathway of E. ramulus was confirmed by biotransformations of flavanones into dihydrochalcones. The engineered E. coli strain that expresses both enzymes was used for the conversion of several flavanones, underlining the applicability of this biocatalytic cascade reaction.


Assuntos
Proteínas de Bactérias/metabolismo , Eubacterium/enzimologia , Flavonoides/metabolismo , Liases Intramoleculares/metabolismo , Oxirredutases/metabolismo , Proteínas de Bactérias/genética , Biocatálise , Cristalografia por Raios X , Escherichia coli/metabolismo , Eubacterium/genética , Flavanonas/química , Flavanonas/metabolismo , Flavonoides/química , Liases Intramoleculares/genética , Oxirredutases/genética , Estrutura Quaternária de Proteína , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Análise de Sequência de DNA
4.
J Agric Food Chem ; 72(26): 14874-14886, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38885647

RESUMO

A modified aroma extract dilution approach (AEDA), followed by the determination of flavor dilution (FD) factors, a quantitative analysis and calculation of the relative flavor activity (RFA) and odor activity values (OAVs) as well as recombination experiments were conducted to evaluate the odor- and taste-relevant components of cold-pressed Citrus latifolia peel oil. A 2-fold concentration by distillation and reanalysis, compared with the original oil, revealed relevant components. Partition of the odor-active substances into four reconstitution groups according to their respective FD factors, followed by a recombination, allowed for a better understanding of the contribution of each FD-factor group to the overall aroma. Especially α-pinene, limonene, γ-terpinene, and 7-methoxycoumarin contribute significantly to the distinct aroma profile of C. latifolia. Heptadecanal (CAS 629-90-3) was described for the first time as an odor-active substance in an enriched C. latifolia peel oil. Campherenyl acetate (CAS 18530-07-9) was identified in nature for the first time and described with a herbal, minty and citrus-like odor. The odor profile of the final recombinant mixture, containing 36 components, was similar to cold-pressed C. latifolia peel oil for most descriptors, whereas the taste profile was described as more aldehydic and citral-like.


Assuntos
Citrus , Aromatizantes , Cromatografia Gasosa-Espectrometria de Massas , Odorantes , Paladar , Citrus/química , Odorantes/análise , Aromatizantes/química , Humanos , Frutas/química , Compostos Orgânicos Voláteis/química , Olfato , Óleos de Plantas/química , Feminino , Limoneno/química , Limoneno/análise , Masculino , Adulto
5.
J Agric Food Chem ; 72(17): 10014-10022, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38626782

RESUMO

Citrus fruits have been known and valued for their aroma in food and perfume ever since humans have maintained written records. Often described as the "champagne" of citrus oils, especially cold pressed lime peel oils have raised attention. Particularly peel oils of Citrus latifolia exhibit a pleasant coumarinic, sweet, and balsamic aroma in comparison to its close relative, the Citrus aurantifolia. Those coumarinic notes have not been completely understood until today. Thus, this study aimed to identify the responsible substances and elucidate their contribution and impact on the aroma of cold-pressed lime oil. By combining distillation, fractionation, olfactory detection, and structure elucidation, the responsible key aroma components were identified. A combination of coumarins and their corresponding saturated analogs have been identified to significantly contribute to the typical coumarinic-like aroma, including three new flavor compounds that have not yet been described in the literature as lime oil constituents: 7-methoxy-2-chromanone (3,4-dihydro-7-methoxy-2H-1-benzopyran-2-one; CAS 20921-02-2), 5,7-dimethoxy-2-chromanone (3,4-dihydro-5,7-dimethoxy-2H-1-benzopyran-2-one; CAS 82243-01-4) and 5,6-dihydrobergaptene (5,6-dihydro-4-methoxy-7H-furo[3,2-g][1]benzopyran-7-one; CAS 29050-61-1). The sensorial evaluation of the impact of these components on the lime aroma profile has shown flavor-modulating effects and the ability to enhance aldehydic-peely, juicy, and fruity notes as well as their importance in reproducing the authentic, typical coumarin-like notes.


Assuntos
Compostos de Cálcio , Citrus , Cumarínicos , Aromatizantes , Odorantes , Óxidos , Óleos de Plantas , Paladar , Humanos , Cumarínicos/química , Odorantes/análise , Óleos de Plantas/química , Citrus/química , Aromatizantes/química , Masculino , Feminino , Adulto , Frutas/química , Adulto Jovem , Pessoa de Meia-Idade , Olfato , Cromatografia Gasosa-Espectrometria de Massas
6.
Hum Brain Mapp ; 34(1): 62-76, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22020878

RESUMO

Excessive intake of dietary salt (sodium chloride) may increase the risk of chronic diseases. Accordingly, various strategies to reduce salt intake have been conducted. This study aimed to investigate whether a salty-congruent odor can enhance saltiness on the basis of psychophysical (Experiment 1) and neuroanatomical levels (Experiment 2). In Experiment 1, after receiving one of six stimulus conditions: three odor conditions (odorless air, congruent, or incongruent odor) by two concentrations (low or high) of either salty or sweet taste solution, participants were asked to rate taste intensity and pleasantness. In Experiment 2, participants received the same stimuli during the functional magnetic resonance imaging scan. In Experiment 1, compared with an incongruent odor and/or odorless air, a congruent odor enhanced not only taste intensity but also either pleasantness of sweetness or unpleasantness of saltiness. In Experiment 2, a salty-congruent combination of odor and taste produced significantly higher neuronal activations in brain regions associated with odor-taste integration (e.g., insula, frontal operculum, anterior cingulate cortex, and orbitofrontal cortex) than an incongruent combination and/or odorless air with taste solution. In addition, the congruent odor-induced saltiness enhancement was more pronounced in the low-concentrated tastant than in the high-concentrated one. In conclusion, this study demonstrates the congruent odor-induced saltiness enhancement on the basis of psychophysical and neuroanatomical results. These findings support an alternative strategy to reduce excessive salt intake by adding salty-congruent aroma to sodium reduced food. However, there are open questions regarding the salty-congruent odor-induced taste unpleasantness.


Assuntos
Imageamento por Ressonância Magnética , Odorantes , Percepção Olfatória/fisiologia , Cloreto de Sódio na Dieta/administração & dosagem , Percepção Gustatória/fisiologia , Adulto , Encéfalo/fisiologia , Mapeamento Encefálico/métodos , Dieta Hipossódica , Sacarose Alimentar/administração & dosagem , Feminino , Indústria Alimentícia/métodos , Preferências Alimentares/fisiologia , Humanos , Masculino , Olfato/fisiologia , Paladar/fisiologia , Adulto Jovem
7.
Ann Rheum Dis ; 71(11): 1839-48, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22586173

RESUMO

OBJECTIVES: Gouty arthritis patients for whom non-steroidal anti-inflammatory drugs and colchicine are inappropriate have limited treatment options. Canakinumab, an anti-interleukin-1ß monoclonal antibody, may be an option for such patients. The authors assessed the efficacy/safety of one dose of canakinumab 150 mg (n=230) or triamcinolone acetonide (TA) 40 mg (n=226) at baseline and upon a new flare in frequently flaring patients contraindicated for, intolerant of, or unresponsive to non-steroidal anti-inflammatory drugs and/or colchicine. Core study co-primary endpoints were pain intensity 72 h postdose (0-100 mm visual analogue scale and time to first new flare. METHODS: Two 12-week randomised, multicentre, active-controlled, double-blind, parallel-group core studies with double-blind 12-week extensions (response in acute flare and in prevention of episodes of re-flare in gout (ß-RELIEVED and ß-RELIEVED-II)). RESULTS: 82.6% patients had comorbidities. Mean 72-h visual analogue scale pain score was lower with canakinumab (25.0 mm vs 35.7 mm; difference, -10.7 mm; 95% CI -15.4 to -6.0; p<0.0001), with significantly less physician-assessed tenderness and swelling (ORs=2.16 and 2.74; both p≤0.01) versus TA. Canakinumab significantly delayed time to first new flare, reduced the risk of new flares by 62% versus TA (HR: 0.38; 95% CI 0.26 to 0.57) in the core studies and by 56% (HR: 0.44; 95% CI 0.32 to 0.60; both p≤0.0001) over the entire 24-week period, and decreased median C-reactive protein levels (p≤0.0001 at 72 h and 7 days). Over the 24-week period, adverse events were reported in 66.2% (canakinumab) and 52.8% (TA) and serious adverse events were reported in 8.0% (canakinumab) and 3.5% (TA) of patients. Adverse events reported more frequently with canakinumab included infections, low neutrophil count and low platelet count. CONCLUSION: Canakinumab provided significant pain and inflammation relief and reduced the risk of new flares in these patients with acute gouty arthritis.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Artrite Gotosa/tratamento farmacológico , Supressores da Gota/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
8.
Food Chem X ; 15: 100446, 2022 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-36211761

RESUMO

Currently, there is limited insight into the influence of the different binding sites of agonists and antagonists of the sweet taste receptor TAS1R2/TAS1R3 on temporal sensory properties of sweet tasting compounds. We investigated whether the binding site and a competitive or allosteric inhibition of TAS1R2/TAS1R3 influence the time-dependent sensory perception and in vitro TAS1R2/TAS1R3-activation profiles. We compared time-intensity ratings of cyclamate, NHDC, acesulfame K, and aspartame with and without lactisole with the corresponding TAS1R2/TAS1R3-activation in transfected HEK293 cells. In combination with lactisole, cyclamate and NHDC demonstrated a shift of the dose-response curve corresponding to a competitive inhibition by lactisole in the sensory and the cell experiments. Allosteric inhibition by lactisole for aspartame and acesulfame K was seen in the cell experiments, but not the sensory ratings. In conclusion, the data do not support a major impact of the binding site on the time-intensity profile of the tested sweeteners.

9.
Ann Rheum Dis ; 70(7): 1264-71, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21540198

RESUMO

OBJECTIVE: This study assessed the efficacy and safety of canakinumab, a fully human anti-interleukin 1ß monoclonal antibody, for prophylaxis against acute gouty arthritis flares in patients initiating urate-lowering treatment. METHODS: In this double-blind, double-dummy, dose-ranging study, 432 patients with gouty arthritis initiating allopurinol treatment were randomised 1:1:1:1:1:1:2 to receive: a single dose of canakinumab, 25, 50, 100, 200, or 300 mg subcutaneously; 4×4-weekly doses of canakinumab (50+50+25+25 mg subcutaneously); or daily colchicine 0.5 mg orally for 16 weeks. Patients recorded details of flares in diaries. The study aimed to determine the canakinumab dose having equivalent efficacy to colchicine 0.5 mg at 16 weeks. RESULTS: A dose-response for canakinumab was not apparent with any of the four predefined dose-response models. The estimated canakinumab dose with equivalent efficacy to colchicine was below the range of doses tested. At 16 weeks, there was a 62% to 72% reduction in the mean number of flares per patient for canakinumab doses ≥50 mg versus colchicine based on a negative binomial model (rate ratio: 0.28-0.38, p≤0.0083), and the percentage of patients experiencing ≥1 flare was significantly lower for all canakinumab doses (15% to 27%) versus colchicine (44%, p<0.05). There was a 64% to 72% reduction in the risk of experiencing ≥1 flare for canakinumab doses ≥50 mg versus colchicine at 16 weeks (hazard ratio (HR): 0.28-0.36, p≤0.05). The incidence of adverse events was similar across treatment groups. CONCLUSIONS: Single canakinumab doses ≥50 mg or four 4-weekly doses provided superior prophylaxis against flares compared with daily colchicine 0.5 mg.


Assuntos
Alopurinol/uso terapêutico , Anticorpos Monoclonais/administração & dosagem , Artrite Gotosa/prevenção & controle , Supressores da Gota/administração & dosagem , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Alopurinol/efeitos adversos , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Artrite Gotosa/sangue , Artrite Gotosa/tratamento farmacológico , Proteína C-Reativa/metabolismo , Colchicina/administração & dosagem , Colchicina/efeitos adversos , Colchicina/uso terapêutico , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Quimioterapia Combinada , Feminino , Supressores da Gota/efeitos adversos , Supressores da Gota/uso terapêutico , Humanos , Interleucina-1beta/antagonistas & inibidores , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
10.
BMC Musculoskelet Disord ; 12: 153, 2011 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-21736751

RESUMO

BACKGROUND: Canakinumab is a fully human anti-interleukin IL-1beta monoclonal antibody, being investigated for the treatment of rheumatoid arthritis (RA). This multicenter, phase II, randomized, double-blind, placebo-controlled, parallel-group, dose-finding study investigated the efficacy and safety of canakinumab in patients with active RA despite ongoing therapy at stable doses of methotrexate. METHODS: Patients were randomized to receive one of four regimens, in addition to methotrexate, for 12 weeks: canakinumab 150 mg subcutaneously (SC) every 4 weeks (q4wk), canakinumab 300 mg SC (2 injections of 150 mg SC) every 2 weeks, a 600 mg intravenous loading dose of canakinumab followed by 300 mg SC every 2 weeks', or placebo SC every 2 weeks. RESULTS: Among 274 patients with evaluable efficacy data, the percentage of responders according to American College of Rheumatology 50 criteria (the primary endpoint, based on a 28-joint count) was significantly higher with canakinumab 150 mg SC q4wk than with placebo (26.5% vs. 11.4%, respectively; p = 0.028). Compared to placebo, this dosage of canakinumab was also associated with significantly more favorable responses at week 12 with respect to secondary endpoints including the Disease Activity Score 28, scores on the Health Assessment Questionnaire and Functional Assessment of Chronic Illness Therapy-Fatigue, swollen 28-joint count, and patient's and physician's global assessments of disease activity. No safety concerns were raised with canakinumab therapy, particularly with regard to infections. Few injection-site reactions occurred. CONCLUSION: The addition of canakinumab 150 mg SC q4wk improves therapeutic responses among patients who have active RA despite stable treatment with methotrexate. TRIAL REGISTRATION: (ClinicalTrials.gov identifier: NCT00784628).


Assuntos
Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Antirreumáticos/administração & dosagem , Antirreumáticos/efeitos adversos , Artrite Reumatoide/tratamento farmacológico , Interleucina-1beta/antagonistas & inibidores , Adulto , Idoso , Anticorpos Monoclonais Humanizados , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Quimioterapia Combinada/efeitos adversos , Quimioterapia Combinada/métodos , Feminino , Humanos , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/efeitos adversos , Interleucina-1beta/imunologia , Masculino , Metotrexato/administração & dosagem , Pessoa de Meia-Idade
11.
Mol Nutr Food Res ; 65(2): e2000472, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33249735

RESUMO

SCOPE: This study investigates the effect of the sweetness of a sucrose versus an isocaloric glucose solution in dietary concentrations on blood glucose regulation by adjusting the sweetness level using the sweet taste inhibitor lactisole. METHODS AND RESULTS: A total of 27 healthy males participated in this randomized, crossover study with four treatments: 10% glucose, 10% sucrose, 10% sucrose + 60 ppm lactisole, and 10% glucose + 60 ppm lactisole. Plasma glucose, insulin, glucagon-like peptide 1, and glucagon levels are measured at baseline and 15, 30, 60, 90, and 120 min after beverage consumption. Test subjects rated the sucrose solution to be sweeter than the isocaloric glucose solution, whereas no difference in sweetness is reported after addition of lactisole to the sucrose solution. Administration of the less sweet glucose solution versus sucrose led to higher blood glucose levels after 30 min, as reflected by a lower ΔAUC for sucrose (1072 ± 136) than for glucose (1567 ± 231). Application of lactisole leads to no differences in glucose, insulin, or glucagon responses induced by sucrose or glucose. CONCLUSION: The results indicate that the structure of the carbohydrate has a stronger impact on the regulation of blood glucose levels than the perceived sweetness.


Assuntos
Glicemia/metabolismo , Glucose/administração & dosagem , Sacarose/administração & dosagem , Percepção Gustatória , Administração Oral , Adolescente , Adulto , Glicemia/análise , Glucagon/sangue , Peptídeo 1 Semelhante ao Glucagon/sangue , Voluntários Saudáveis , Humanos , Insulina/sangue , Masculino , Pessoa de Meia-Idade , Adulto Jovem
12.
Curr Res Toxicol ; 2: 192-201, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34345860

RESUMO

In a 90-day GLP-compliant study groups of Sprague-Dawley rats (10/sex/group) were fed diets containing ß-ionone epoxide, a fragrance material and a flavoring substance, at dietary concentrations providing target intakes of 0, 20, 40 and 80 mg/kg bw/day. There were no deaths and no adverse changes in clinical observations, ophthalmological examinations, body weight, body weight gain, food consumption, food efficiency; hematology, serum chemistry, urinalysis parameters; or in macroscopic findings attributable to ß-ionone epoxide administration. Increased absolute and relative liver weights in high dose females without correlating hepatic histopathological findings were considered non-adverse. Cortical vacuolation of adrenal zona fasciculata was observed in high-dose males but was considered non-adverse due to the nondegenerative nature of this alteration. ß-Ionone epoxide did not influence estrus cyclicity in females and did not affect sperm morphology or epididymal sperm count, homogenization-resistant spermatid count and motility measurements in male rats. The no-observed-adverse-effect level (NOAEL) for administration of ß-ionone epoxide in the diet was determined to be the highest dose tested of 80 mg/kg bw/day.

13.
Artigo em Inglês | MEDLINE | ID: mdl-33170096

RESUMO

Intake assessment and hazard profile of chemical substances are the two critical inputs in a safety assessment. Human intake assessment presents challenges that stem either from the absence of data or from numerous sources of variability and uncertainty, which have led regulators to adopt conservative approaches that inevitably overestimate intake. Refinements of intake assessments produce more realistic estimates and help prioritise areas of concern and better direct investment of resources. However, use levels (ULs), which represent the usual added amount of flavourings to food products, are the starting point for refined intake assessments, are data-intensive, and data availability is often a limitation. The work presented here was undertaken to investigate the use level patterns of substances used as flavourings in foods and to develop a systematic tool for data extrapolation based on chemical structure. The available dataset consists of use levels reported through eight industry surveys and hence are representative of industry uses rather than regulatory limits, which are higher by design and not realistic. A systematic statistical analysis was undertaken to determine whether the industry-reported UL data can be used to estimate use levels of flavouring substances belonging to the same chemical group for which such data are not available. Predictive modelling approaches were explored to evaluate relationships in the data and utilised additional variables relevant to technological considerations, such as volatility losses upon heat treatment, and Tanimoto index-based pair-wise structural similarity scores to determine whether more granular similarity information can reduce the within-group variability. The analyses indicated that the use levels of flavouring substances can reasonably be estimated based on the available data using chemical group classifications stratified by food category. Source of uncertainty and limitations are discussed.


Assuntos
Inquéritos sobre Dietas , Ingestão de Alimentos , Aromatizantes/análise , Análise de Alimentos , Contaminação de Alimentos/análise , Aromatizantes/administração & dosagem , Inocuidade dos Alimentos , Humanos
14.
Nutrients ; 12(10)2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33066498

RESUMO

Knowledge regarding the involvement of sweetness perception on energy intake is scarce. Here, the impact of glucose and sucrose sweetness, beyond their caloric load, on subsequent food intake and biomarkers of satiation was evaluated by co-administration of the sweet taste receptor inhibitor lactisole. A total of 27 healthy, male subjects received solutions of either 10% glucose w/o 60 ppm lactisole or 10% sucrose w/o 60 ppm lactisole. Subsequent food intake from a standardized breakfast was evaluated 2 h after receiving the respective test solution. Changes in postprandial plasma concentrations of cholecystokinin, ghrelin, and serotonin were determined over a period of 120 min, as was the body temperature. Administration of lactisole to the sucrose solution increased the energy intake from the subsequent standardized breakfast by 12.9 ± 5.8% (p = 0.04), led to a decreased Δ AUC of the body core temperature by 46 ± 20% (p = 0.01), and time-dependently reduced Δ serotonin plasma concentrations (-16.9 ± 6.06 ng/mL vs. -0.56 ± 3.7 ng/mL after sucrose administration, p = 0.03). The present study shows that lactisole increases energy intake and decreases plasma serotonin concentrations as well as body core temperature induced by sucrose, but not glucose. This finding may be associated with the different binding affinities of sucrose and glucose to the sweet taste receptor.


Assuntos
Derivados de Benzeno/administração & dosagem , Sacarose Alimentar/administração & dosagem , Ingestão de Alimentos/fisiologia , Ingestão de Energia/fisiologia , Saciação/fisiologia , Serotonina/sangue , Serotonina/metabolismo , Bebidas Adoçadas com Açúcar , Papilas Gustativas/metabolismo , Percepção Gustatória/fisiologia , Adolescente , Adulto , Temperatura Corporal , Desjejum , Colecistocinina/sangue , Sacarose Alimentar/metabolismo , Grelina/sangue , Glucose/metabolismo , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Prandial , Adulto Jovem
15.
J Agric Food Chem ; 68(32): 8613-8620, 2020 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-32662269

RESUMO

So far, the occurrence of the flavor constituent 1-phenylethyl acetate in a natural source has not been unambiguously confirmed. The present work provides the detailed identification of 1-phenylethyl acetate from clove (Syzygium aromaticum (L.) Merr. & L.M. Perry) buds. In addition, headspace solid-phase microextraction-gas chromatography/mass spectrometry (GC/MS) analysis revealed further occurrence of 1-phenylethyl acetate in cocoa pulp and grape hyacinth flowers. A total of 15.2 g of essential oil was recovered from 7.2 kg of clove buds by simultaneous distillation-extraction followed by vacuum distillation. The distillate obtained was fractionated by silica column chromatography, whereby a significant enrichment of 1-phenylethyl acetate was achieved. The fraction containing the target analyte was further purified by preparative high-performance liquid chromatography, resulting in a final purity of ∼93.0%, yielding a total of 1 to 2 mg of 1-phenylethyl acetate. Identification of the isolated compound was achieved by GC/MS, infrared spectroscopy, enantioselective GC, isotope ratio MS, and nuclear magnetic resonance spectroscopy. Enantioselective GC/MS analysis revealed an enantiomeric excess of 60% (1S)-(-)-1-phenylethyl acetate in the isolate. The δ13CV-PDB value of -32.5 ± 0.5‰ was in accordance with that of C3-plants and other constituents found in genuine clove extracts.


Assuntos
Acetatos/análise , Aromatizantes/química , Extratos Vegetais/química , Syzygium/química , Cromatografia Gasosa-Espectrometria de Massas , Estrutura Molecular , Odorantes/análise , Óleos Voláteis/química
16.
Food Chem X ; 7: 100100, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-32904296

RESUMO

A reduction in sugar consumption is desirable from a health point of view. However, the sensory profiles of alternative sweet tasting compounds differ from sucrose regarding their temporal profile and undesired side tastes, reducing consumers' acceptance. The present study describes a sensory characterization of a variety of sweet and sweet taste affecting compounds followed by a comparison of similarity to sucrose and a multivariate regression analysis to investigate structural determinants and possible interactions for the temporal profile of the sweetness and side-tastes. The results of the present study suggest a pivotal role for the number of ketones, aromatic rings, double bonds and the M LogP in the temporal profile of sweet and sweet taste affecting compounds. Furthermore, interactions between aggregated physicochemical descriptors demonstrate the complexity of the sensory response, which should be considered in future models to predict a comprehensive sensory profile of sweet and sweet taste affecting compounds.

17.
J Agric Food Chem ; 68(11): 3434-3444, 2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-31891507

RESUMO

This study aimed at identifying whether the bitter-tasting amino acids l-arginine (l-ARG) and l-isoleucine (l-ILE) differentially regulate mechanisms of gastric acid secretion in human parietal cells (HGT-1 cells) via activation of bitter taste sensing receptors (T2Rs). In a first set of experiments, involvement of T2Rs in l-ARG and l-ILE-modulated proton secretion was demonstrated by co-treatment of HGT-1 cells with T2R antagonists. Subsequent whole genome screenings by means of cDNA arrays revealed T2R1 as a prominent target for both amino acids. Next, the functional role of T2R1 was verified by means of a T2R1 CRISPR-Cas9 knock-out approach. Here, the effect of l-ARG on proton secretion decreased by 65.7 ± 21.9% and the effect of l-ILE increased by 93.2 ± 24.1% in HGT-1 T2R1 ko versus HGT-1 wt cells (p < 0.05). Overall, our results indicate differential effects of l-ARG and l-ILE on proton secretion in HGT-1 cells and our molecular docking studies predict distinct binding for these amino acids in the binding site of T2R1. Further studies will elucidate whether the mechanism of differential effects involves structure-specific ligand-biased signaling of T2R1 or additional cellular targets.


Assuntos
Isoleucina , Paladar , Aminoácidos , Arginina , Humanos , Simulação de Acoplamento Molecular , Prótons , Receptores Acoplados a Proteínas G/genética
18.
Food Chem Toxicol ; 135: 110876, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31610257

RESUMO

Two independent 90-day GLP-compliant studies were conducted in Sprague-Dawley rats with ß-caryophyllene or ß-caryophyllene epoxide, two common flavoring and fragrance materials. Dietary concentrations of ß-caryophyllene were 3500; 7000; and 21,000 ppm for males and 3500; 14,000; and 56,000 ppm for females. Dietary concentrations of ß-caryophyllene epoxide were 1750; 10,500; and 21,000 ppm. There were no deaths or clinical toxicity attributable to either substance administration. Statistically significant, dose-dependent reductions in body weight, body weight gain, food consumption, and food efficiency at the highest dietary concentrations of ß-caryophyllene, but not of ß-caryophyllene epoxide, were attributed to palatability issues. Neither ß-caryophyllene nor ß-caryophyllene epoxide influenced estrus cyclicity or sperm parameters. Macroscopic and microscopic findings were primarily related to changes in the kidneys of male rats, consistent with α2u-globulin nephropathy, and in the liver of male and female rats, including hepatocyte hypertrophy at the middle and high intake levels. These changes correlated with increased absolute and relative organ weights. Since the kidney findings were a species- and sex-specific effect, the NOAEL in each study was based on hepatocyte hypertrophy at the two highest dietary concentrations and were determined to be 222 mg/kg bw/day for ß-caryophyllene and 109 mg/kg bw/day for ß-caryophyllene epoxide.


Assuntos
Sesquiterpenos Policíclicos/administração & dosagem , Animais , Relação Dose-Resposta a Droga , Compostos de Epóxi/administração & dosagem , Feminino , Masculino , Nível de Efeito Adverso não Observado , Sesquiterpenos Policíclicos/química , Sesquiterpenos Policíclicos/toxicidade , Ratos , Ratos Sprague-Dawley , Testes de Toxicidade
19.
Mol Nutr Food Res ; 63(23): e1900133, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31535460

RESUMO

SCOPE: Increasing the intake of satiety-enhancing food compounds represents a promising strategy for maintaining a healthy body weight. Recently, satiating effects for the capsaicinoid nonivamide have been demonstrated. As various proteins and amino acids have also been demonstrated to decrease energy intake, oral glucose tolerance test (oGTT)-based bolus interventions of 75 g glucose + 0.15 mg nonivamide (NV control) are tested with/without combination of a wheat protein hydrolysate (WPH: 2 g) and/or l-arginine (ARG: 3.2 g) for their satiating effects in 27 moderately overweight male subjects. METHODS AND RESULTS: Compared to NV control intervention, ARG and WPH + ARG treatment both reduce (p < 0.01) total calorie intake from a standardized breakfast by -5.9 ± 4.15% and -6.07 ± 4.38%, respectively. For the WPH + ARG intervention, increased mean plasma serotonin concentrations (AUC: 350 ± 218), quantitated by ELISA, and delayed gastric emptying, assessed by 13 C-Na-acetate breath test (-2.10 ± 0.51%, p < 0.05), are demonstrated compared to NV control. Correlation analysis between plasma serotonin and gastric emptying reveals a significant association after WPH ± ARG intervention (r = -0.396, p = 0.045). CONCLUSION: Combination of WPH and ARG enhances the satiating effect of nonivamide, providing opportunities to optimize satiating food formulations by low amounts of the individual food constituents.


Assuntos
Arginina/administração & dosagem , Capsaicina/análogos & derivados , Sobrepeso/psicologia , Hidrolisados de Proteína/administração & dosagem , Saciação/efeitos dos fármacos , Triticum/química , Adulto , Capsaicina/farmacologia , Estudos Cross-Over , Ingestão de Energia , Esvaziamento Gástrico/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Serotonina/sangue , Método Simples-Cego
20.
Artigo em Inglês | MEDLINE | ID: mdl-31585634

RESUMO

2,4-Decadienal (E,E-) occurs naturally in foods and is also used as a flavoring ingredient. In vivo micronucleus studies were used to evaluate the potential for 2,4-decadienal to cause genotoxic effects. Male Han Wistar rats were dosed either by intraperitoneal injection or by gavage in two independent studies. The animals (12/group) received 25, 50, or 100 mg/kg bw of 2,4-decadienal via intraperitoneal injection, or 350, 700, or 1400 mg/kg bw via gavage. Dose-dependent decreases in the percentages of peripheral blood reticulocytes were observed in both studies, indicating that the target tissue was exposed to toxic levels of 2,4-decadienal. No induction of micronuclei in the bone marrow polychromatic erythrocytes or the peripheral blood reticulocytes was observed in either study. These results, coupled with previous mutagenicity studies, support the overall conclusion that 2,4-decadienal does not present a concern for genotoxicity.


Assuntos
Aldeídos/toxicidade , Aromatizantes/toxicidade , Administração Oral , Aldeídos/administração & dosagem , Animais , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/ultraestrutura , Relação Dose-Resposta a Droga , Aromatizantes/administração & dosagem , Injeções Intraperitoneais , Masculino , Testes para Micronúcleos/métodos , Distribuição Aleatória , Ratos , Ratos Wistar , Reticulócitos/efeitos dos fármacos , Reticulócitos/ultraestrutura
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