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1.
J Agric Food Chem ; 70(24): 7447-7459, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35679324

RESUMO

Plant pathogens such as Phytophthora infestans that caused the Irish Potato Famine continue to threaten local and global food security. Genetic and chemical plant protection measures are often overcome by adaptation of pathogen population structures. Therefore, there is a constant demand for new, consumer- and environment-friendly plant protection strategies. Metabolic alterations induced by P. infestans in the foliage and tubers of six different potato cultivars were investigated. Using a combination of untargeted metabolomics, isolation techniques, and structure elucidation by MS and 1D/2D-NMR experiments, five steroidal glycoalkaloids, five oxylipins, and four steroidal saponins were identified. As the steroidal saponins showed antioomycete but no hemolytic activity, they may thus be considered as probably safe target substances for enrichment in breeding programs for disease resistance and as chemical lead structures for the production of nature-derived synthetic antioomycetes.


Assuntos
Phytophthora infestans , Saponinas , Solanum tuberosum , Genótipo , Melhoramento Vegetal , Doenças das Plantas/genética , Doenças das Plantas/prevenção & controle , Saponinas/farmacologia , Solanum tuberosum/genética
2.
Food Chem ; 392: 133291, 2022 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-35636189

RESUMO

Fractionation of high molecular weight (HMW) coffee melanoidins of varying roasting intensity and evaluation of aroma binding activity via nuclear magnetic resonance spectroscopy revealed two fractions 5-10 kDa and > 50 kDa with high and selective binding affinity toward key coffee odorants. Quantification of monosaccharides, amino acids and phenolic acids, as well as aliphatic organic acids in hydrolysates of HMW material indicated the importance of aromatic residues in the form of hydroxycinnamic acids for the formation of non-covalent interactions with odorants. Caffeic acid concentrations were up to four times higher in fractions 5-10 kDa and > 50 kDa compared to 30-50 kDa and 10-30 kDa fractions. A minimization strategy was developed involving alkaline treatment of the most affine HMW fractions followed by reconstitution at typical coffee concentrations. These reconstituted HMW fractions exhibited up to 25% less aroma binding compared to native fractions of coffee.


Assuntos
Café , Odorantes , Bebidas , Café/química , Temperatura Alta , Polímeros/química
3.
J Agric Food Chem ; 70(17): 5427-5437, 2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35467336

RESUMO

A holistic ultraperformance liquid chromatography (UPLC)-time of flight (TOF)-mass spectrometry-based approach was used to screen for storage-induced reaction products consisting of the volatile key coffee thiols methanethiol, 2-furfurylthiol, 2-methyl-3-furanthiol, 3-mercapto-3-methylbutanol, and 3-mercapto-2-butanone and low-molecular weight phenolic constituents of coffee beverages including chlorogenic acid, caffeic acid, and their thermal degradation products hydroxyhydroquinone, catechol, and 4-ethylcatechol. Multiple marker compounds could be detected in thiol-enriched coffee brews after UPLC-TOF-MS profiling and statistical data analysis. Subsequently, marker compounds were synthesized and structurally characterized via high-resolution mass spectrometry and 1D- and 2D-NMR experiments. Quantification of these reaction products in fresh and stored coffee beverages was realized in native coffee and after stir bar sorptive extraction with liquid desorption by means of UHPLC-MS/MS. The quantitative data revealed the biggest influence of storage time on the formation of reaction products between hydroxyhydroquinone and methanethiol and 2-furfurylthiol, while other reaction products were only slightly affected by storage and thus most likely formed during the roasting process.


Assuntos
Ácido Clorogênico , Café , Ácidos Cafeicos , Ácido Clorogênico/química , Café/química , Odorantes/análise , Compostos de Sulfidrila/química , Espectrometria de Massas em Tandem
4.
J Agric Food Chem ; 70(14): 4382-4390, 2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35364812

RESUMO

Linseed oil is rich in unsaturated fatty acids, and its increased consumption could aid in health-promoting nutrition. However, rapid oxidation of linseed oil and concomitant development of bitterness impair consumers' acceptance. Previous research revealed that cyclolinopeptides, a group of cyclic peptides inherent to linseed oil, dominantly contribute to the observed bitterness. In the present study, fresh and stored linseed oil and flaxseed were analyzed for the presence of cyclolinopeptides using preparative high-performance liquid chromatography combined with mass spectrometry- and nuclear magnetic resonance-based identification and quantification. The purified compounds were tested for the activation of all 25 human bitter taste receptors of which only two responded exclusively to methionine-oxidized cyclolinopeptides. Of those, the methionine sulfoxide-containing cyclolinopeptide-4 elicited responses at relevant concentrations. We conclude that this compound is the main determinant of linseed oil's bitterness and propose strategies to reduce the development of bitterness.


Assuntos
Linho , Óleo de Semente do Linho , Idoso , Cromatografia Líquida de Alta Pressão/métodos , Linho/química , Humanos , Óleo de Semente do Linho/química , Peptídeos Cíclicos/química , Paladar
5.
J Agric Food Chem ; 69(50): 15334-15344, 2021 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-34874702

RESUMO

A quantitative 1H NMR-based approach was established, which allowed the direct and noninvasive analysis of molecular interactions between key coffee odorants and high-molecular-weight (HMW) melanoidin polymers. A clear distinction between covalent and noncovalent interactions was achieved by monitoring the time dependency of odorant-polymer interactions, resulting in four scenarios: covalent, π-π, covalent and π-π-, as well as no interactions. Evaluation of temperature influence on e.g. 2-furfurylthiol (FFT), revealed an altered behavior with increased π-π stacking at lower temperatures and accelerated covalent interactions at higher temperatures. Human sensory experiments with HMW material and a coffee aroma reconstitution model showed a drastic reduction of "roasty/sulfury" aroma notes, as well as an increased "sweetish/caramel-like" flavor. The lack of interactions between the "sweetish/caramel" smelling 4-hydroxy-2,5-dimethyl-3(2H)-furanone with the HMW melanoidins in combination with the high binding affinity of coffee thiols explains the sensory evaluation and is obviously the reason for the fast disappearance of the typical "roasty/sulfury" aroma impressions of a freshly prepared coffee brew.


Assuntos
Café , Odorantes , Bebidas/análise , Humanos , Odorantes/análise , Polímeros
6.
J Chromatogr A ; 1658: 462608, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34666269

RESUMO

Aside from Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD), other less common cannabinoids have recently gained an increasing popularity, mostly due to their promising biological potential. However, time-saving and cost-effective methods for their preparative purification are missing. In this study, trapping multiple dual mode (MDM), a flow-reversal liquid-liquid chromatography (LLC) operating mode, was used for the separation of different minor cannabinoids from a hemp extract. Separation task specific biphasic solvent systems were selected for the purification of the target constituents, as follows: n-hexane/methanol/water 10/6.5/3.5 for cannabielsoin (CBE); n-hexane/methanol/water 10/7/3 for cannabidivarin (CBDV) and cannabigerol (CBG); n-hexane/methanol/water 10/8/2 for cannabinol (CBN) and n-hexane/methanol/water 10/9/1 for cannabichromene (CBC) and cannabicylol (CBL). For each separation task, the concentration of the hemp extract in the feed stream and mobile phase flow rate were selected by shake-flask and stationary phase retention experiments, respectively. For the determination of the trapping MDM operating parameters, the short-cut method was implemented and followed by equilibrium-cell model-based simulations. The trapping MDM allowed the separation of the targeted cannabinoids with purities of 93-99%, yields of 73-95%, solvent consumption 2-4-fold lower and productivities almost double than those obtained using batch separation.


Assuntos
Canabinoides , Cannabis , Canabinoides/análise , Cromatografia Líquida , Dronabinol , Extratos Vegetais
7.
Food Chem ; 365: 130461, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34229992

RESUMO

α-Solanine and α-chaconine are the major glycoalkaloids (SGAs) in potatoes, but up to now the biosynthesis of these saponins is not fully understood. In planta13CO2 labeling experiments monitored by nuclear magnetic resonance spectroscopy (NMR) and high-resolution mass spectrometry (HRMS) unraveled the SGA biosynthetic pathways from CO2 photosynthates via early precursors to the SGAs. After a pulse of ~ 700 ppm 13CO2 for four hours, followed by a chase period for seven days, specific 13C-distributions were detected in SGAs from the leaves of the labeled plant. NMR analysis determined the positional 13C-enrichments in α-solanine and α-chaconine characterized by 13C2-pairs in their aglycones. These patterns were in perfect agreement with a mevalonate-dependent biosynthesis of the isopentenyl diphosphate and dimethylallyl diphosphate precursors. The 13C-distributions also suggested cyclization of the 2,3-oxidosqualene precursor into the solanidine aglycone backbone involving a non-stereoselective hydroxylation step of the sterol a mixture of 25S-/25R-epimers of the SGAs.


Assuntos
Solanina , Solanum tuberosum , Vias Biossintéticas , Dióxido de Carbono , Folhas de Planta
8.
Eur J Radiol ; 141: 109813, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34116453

RESUMO

PURPOSE: We evaluated the accuracy of preoperative CT in staging colonic diverticulitis (ACD) by using the classification of diverticular disease (CDD) and investigated the diagnostic impact of water enema (WE) and visceral obesity. METHODS: In this retrospective study, the radiological and hospital information system was searched for patients who underwent CT for clinically suspected ACD prior to surgery between 2009 and 2019. From the initial population (n = 164), we included 155 patients (94.5 %) (85 women; mean age: 58 ±â€¯13 years) matching the following inclusion criteria: i.) clinically suspected ACD, ii.) i.v. contrast-enhanced CT, iii.) surgery for ACD within 1 week after CT, iv.) histopathological report that proved ACD. The remaining 9 patients (5.5 %) were excluded because histopathological reports were lacking (n = 3) or CT was performed without intravenous contrast agent (n = 6). WE (+ butylscopolamine i.v.) was performed in 93 patients (group A, 60 %). 62 patients (group B, 40 %) had no WE. Visceral-to-subcutaneous fat ratio (V/S) was determined for each patient. Two radiologists blinded for final diagnosis independently staged ACD according to CDD and assessed prevalence and confidence ratings of ACD-related CT-findings: pericolonic fat stranding, covered- and free-perforation, local and generalized peritonitis, abscess. Interobserver-agreement of CT-findings were assessed and effects of WE and V/S ratio on the diagnostic accuracy of CT with surgical and histopathological findings as reference were determined by calculating a logistic regression model. RESULTS: CT-staging showed high accuracy (94 %) and excellent interrater-correlation (ICC 0.96) for staging ACD. WE had no positive impact neither on diagnostic accuracy of staging, nor on confidence ratings of ACD-related CT-findings (all p > 0.5). Confidence ratings were significantly higher in examinations without WE for perforation, peritonitis as well as abscesses (all p < 0.5). Confidence ratings for the assessment of local peritonitis improved significantly with higher V/S (p = 0.049). The increase of V/S significantly correlated with the probability for correct CDD staging of ACD in CT (p = 0.023). CONCLUSION: Increase of visceral obesity significantly improves accuracy of CT in preoperative staging acute colonic diverticulitis. However, independently of the degree of visceral obesity, water enema has no diagnostic benefit and may therefore be omitted. Overall, CT proves high accuracy in preoperative staging ACD using the classification of diverticular disease. LEVEL OF EVIDENCE: Retrospective study, observational study.


Assuntos
Doença Diverticular do Colo , Obesidade Abdominal , Doença Aguda , Idoso , Doença Diverticular do Colo/diagnóstico por imagem , Enema , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Água
9.
J Agric Food Chem ; 69(3): 1027-1038, 2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33433215

RESUMO

To gain comprehensive insight into the interactions of key coffee odorants, like the Strecker aldehydes, acetaldehyde, propanal, methylpropanal, 2- and 3-methylbutanal, and methional, and the nonvolatile fraction of coffee, an untargeted metabolomics approach was applied. Ultra performance liquid chromatography (UPLC)-time of flight (TOF)-mass spectrometry (ESI-) profiling followed by statistical data analysis revealed a marker substance for a coffee beverage spiked with acetaldehyde with an accurate mass of 217.0703 [M - H]-. This compound could be identified as a reaction product of quinic acid (QA) and acetaldehyde linked by acetalization at the cis-diol function of QA. Consequently, the acetalization of aldehydes, QA, 5-O-caffeoyl quinic acid (CQA), and quinic acid γ-lactone (QAL) was investigated by means of model reactions, followed by synthesis, isolation, and structure elucidation via UPLC-TOF-MS and 1D and 2D NMR techniques. UHPLC-MS/MSMRM screening and the quantification of aldehyde adducts in coffee beverages revealed the presence of QA/acetaldehyde, -/propanal, -/methylpropanal, and -/methional reaction products and CQA/acetaldehyde, -/propanal, -/methylpropanal, -/2- and 3-methylbutanal, and -/methional and QAL/acetaldehyde adducts for the first time, in concentrations of 12-270 µg/L for QA/aldehydes, 5-225 µg/L for CQA/aldehydes, and 62-173 µg/L for QAL/acetaldehyde. The sensory characterization of the identified compounds showed bitter taste recognition thresholds of 48-297 µmol/L for CQA adducts and 658 µmol/L for QAL/acetaldehyde, while the QA adducts showed no bitter taste (<2000 µmol/L).


Assuntos
Aldeídos/química , Ácido Clorogênico/química , Coffea/química , Lactonas/química , Ácido Quínico/química , Adulto , Cromatografia Líquida de Alta Pressão , Café/química , Culinária , Feminino , Temperatura Alta , Humanos , Masculino , Estrutura Molecular , Sementes/química , Espectrometria de Massas em Tandem , Paladar , Adulto Jovem
10.
Int J Med Inform ; 105: 89-97, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28750915

RESUMO

CONTEXT: Integrated primary care requires systems and service integration along with financial incentives to promote downward substitution to a single entry point to care. Integrated Primary Care Centres (IPCCs) aim to improve integration by co-location of health services. The Informatics Capability Maturity (ICM) describes how well health organisations collect, manage and share information; manage eHealth technology, implementation, change, data quality and governance; and use "intelligence" to improve care. AIM: Describe associations of ICM with systems and service integration in IPCCs. METHODS: Mixed methods evaluation of IPCCs in metropolitan and rural Australia: an enhanced general practice, four GP Super Clinics, a "HealthOne" (private-public partnership) and a Community Health Centre. Data collection methods included self-assessed ICM, document review, interviews, observations in practice and assessment of electronic health record data. Data was analysed and compared across IPCCs. FINDINGS: The IPCCs demonstrated a range of funding models, ownership, leadership, organisation and ICM. Digital tools were used with varying effectiveness to collect, use and share data. Connectivity was problematic, requiring "work-arounds" to communicate and share information. The lack of technical, data and software interoperability standards, clinical coding and secure messaging were barriers to data collection, integration and sharing. Strong leadership and governance was important for successful implementation of robust and secure eHealth systems. Patient engagement with eHealth tools was suboptimal. CONCLUSIONS: ICM is positively associated with integration of data, systems and care. Improved ICM requires a health workforce with eHealth competencies; technical, semantic and software standards; adequate privacy and security; and good governance and leadership.


Assuntos
Prestação Integrada de Cuidados de Saúde , Registros Eletrônicos de Saúde/estatística & dados numéricos , Informática Médica/normas , Atenção Primária à Saúde/normas , Telemedicina/normas , Austrália , Humanos
11.
Int J Technol Assess Health Care ; 31(3): 188-96, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26179277

RESUMO

OBJECTIVES: Health technology reassessment and disinvestment can be difficult due to uncertainties regarding available evidence. Pathology testing to investigate cobalamin (vitamin B12) deficiency is a strong case in point. We conducted a 3-month economic evaluation of five strategies for diagnosing and treating cobalamin deficiency in adult patients hypothetically presenting with new unexplained fatigue in the primary care setting. The first consultation per patient was considered. Screening tests other than serum cobalamin were not included. METHODS: A cost-effectiveness analysis was undertaken using a decision tree to represent the diagnostic / treatment pathways, with relevant cost and utility scores assigned to different stages in the evaluation process. Input parameter values were estimated from published evidence, supplemented by expert opinion, with sensitivity analysis undertaken to represent parameter uncertainty. RESULTS: Ordering serum vitamin B12 to assess cobalamin deficiency among patients with unexplained fatigue was not cost-effective in any patient population, irrespective of pretest prevalence of this deficiency. For patients with a pretest prevalence above 1 percent, treating all with oral vitamin B12 supplements without testing was most cost-effective, whereas watchful waiting with symptoms monitoring was most cost-effective for patients with lower pretest prevalence probabilities. CONCLUSIONS: Substantial evidence gaps exist for parameter estimation: questionable cobalamin deficiency levels in the fatigued; debatable treatment methods; unknown natural history of the condition. Despite this, we reveal a robust path for disinvestment decision making in the face of a paradox between the evidence required to inform disinvestment compared with its paucity in informing initial funding decisions.


Assuntos
Fadiga/sangue , Fadiga/etiologia , Deficiência de Vitamina B 12/complicações , Deficiência de Vitamina B 12/diagnóstico , Vitamina B 12/sangue , Adolescente , Adulto , Idoso , Análise Química do Sangue , Análise Custo-Benefício , Suplementos Nutricionais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Econométricos , Anos de Vida Ajustados por Qualidade de Vida , Vitamina B 12/administração & dosagem , Deficiência de Vitamina B 12/tratamento farmacológico , Adulto Jovem
12.
Magn Reson Chem ; 53(10): 813-20, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26195084

RESUMO

Previous activity-guided phytochemical studies on Garcinia buchananii stem bark, which is traditionally used in Africa to treat various gastrointestinal and metabolic illnesses, revealed xanthones, polyisoprenylated benzophenones, flavanone-C-glycosides, biflavonoids, and/or biflavanones as bioactive key molecules. Unequivocal structure elucidation of biflavonoids and biflavanones by means of NMR spectroscopy is often complicated by the hindered rotation of the monomers around the C-C axis (atropisomerism), resulting in a high spectral complexity. In order to facilitate an unrestricted rotation, NMR spectra are usually recorded at elevated temperatures, commonly over 80 °C, which effects in a single set of resonance signals. However, under these conditions, one of the target compounds of this investigation, (2R,3S,2″R,3″R)-manniflavanone (1), undergoes degradation. Therefore, we demonstrated in the present study that the 1,1-ADEQUATE could be successfully used as a powerful alternative approach to confirm the C-C connectivities in 1, avoiding detrimental conditions. However, a moderate increase in temperature up to 50 °C was sufficient to deliver sharp signals in the proton NMR experiment of (2R,3S,2″R,3″R)-isomanniflavanone (2) and (2″R,3″R)-preussianone (3). In addition, two new compounds could be isolated, namely (2R,3S,2″R,3″R)-GB-2 7″-O-ß-D-glucopyranoside (4) and (2R,3S,2″R,3″R)-manniflavanone-7″-O-ß-D-glucopyranoside (5), and whose structures were elucidated by spectroscopic analysis including 1D and 2D NMR and mass spectrometry methods. The absolute configurations were determined by a combination of NMR and electronic circular dichroism (ECD) spectroscopy. The aforementioned compounds exhibited high anti-oxidative capacity in the H2O2 scavenging, hydrophilic Trolox equivalent antioxidant capacity (H-TEAC) and hydrophilic oxygen radical absorbance capacity (H-ORAC) assays.


Assuntos
Técnicas de Química Analítica/métodos , Flavanonas/química , Flavonas/química , Garcinia/química , Espectroscopia de Ressonância Magnética , Extratos Vegetais/química , Estabilidade de Medicamentos , Temperatura Alta , Estrutura Molecular , Compostos Fitoquímicos , Casca de Planta/química
13.
J Agric Food Chem ; 63(32): 7169-79, 2015 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-26226176

RESUMO

Comparative antioxidative analyses of aqueous ethanolic extracts from leaf, root, and stem of Garcinia buchananii revealed high activity of all three organs. To investigate the metabolite composition of the different parts of G. buchananii, an untargeted metabolomics approach using UPLC-ESI-TOF MS with simultaneous acquisition of low- and high-collision energy mass spectra (MS(e)) was performed. Unsupervised statistics (PCA) highlighted clear differences in the metabolomes of the three organs. OPLS-DA revealed (2R,3S,2″R,3″R)-GB-1, (2R,3S)-morelloflavone, and (2R,3S)-volkensiflavone as the most decisive marker compounds discriminating leaf from root and stem extract. Leaves represent the best source to isolate GB-1, morelloflavone, and volkensiflavone. Root extract is the best organ to isolate xanthones and stem bark extract the best source to isolate (2R,3S,2″R,3″R)-manniflavanone; the identified polyisoprenylated benzophenones are characteristic compounds for the leaf organ. Morelloflavone, volkensiflavone, and garcicowin C were isolated for the first time from G. buchananii, identified via MS, NMR, and CD spectroscopy, and showed in H2O2 scavenging, H/L-TEAC, and H/L-ORAC assays moderate to strong in vitro antioxidative activities.


Assuntos
Antioxidantes/química , Suplementos Nutricionais/análise , Garcinia/química , Extratos Vegetais/química , Antioxidantes/metabolismo , Cromatografia Líquida de Alta Pressão , Garcinia/metabolismo , Espectrometria de Massas , Metabolômica , Estrutura Molecular , Extratos Vegetais/metabolismo , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
14.
Aust Fam Physician ; 41(3): 110-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22396923

RESUMO

BACKGROUND: Osteoporosis remains undertreated in Australian primary care, with as few as 30% of postmenopausal women with a fracture and 10% of men with osteoporosis receiving pharmacological treatment. OBJECTIVE: This article presents an overview of the pharmacological management of osteoporosis in older people in the general practice setting. DISCUSSION: Lifestyle factors and ensuring adequate calcium and vitamin D intake are important in preventing and treating osteoporosis. Pharmacological treatments are recommended for patients with a minimal trauma fracture, for those aged 70 years or over with a T-score of -3.0 or lower, or for those who are currently taking prolonged high dose corticosteroids and who have a T-score of -1.5 or lower. Bisphosphonates are recommended as first line therapy for established postmenopausal osteoporosis. Medicine selection is guided by patient gender, menopausal status, medical and fracture history, patient preference and eligibility for government subsidy.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Cálcio/uso terapêutico , Difosfonatos/uso terapêutico , Fraturas Ósseas/prevenção & controle , Osteoporose/tratamento farmacológico , Vitamina D/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea/efeitos dos fármacos , Feminino , Humanos , Masculino , Osteoporose/prevenção & controle , Fatores de Risco
15.
J Agric Food Chem ; 60(11): 2884-95, 2012 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-22352449

RESUMO

To gain a more comprehensive knowledge on whether, besides the well-known piperine, other compounds are responsible for the pungent and tingling oral impression imparted by black pepper, an ethanol extract prepared from black pepper (Piper nigrum L.) was screened for its key sensory-active nonvolatiles by application of taste dilution analysis (TDA). Purification of the compounds perceived with the highest sensory impact, followed by LC-MS and 1D/2D NMR experiments as well as synthesis, led to the structure determination of 25 key pungent and tingling phytochemicals, among which the eight amides 1-(octadeca-2E,4E,13Z-trienyl)piperidine, 1-(octadeca-2E,4E,13Z-trienyl)pyrrolidine, (2E,4E,13Z)-N-isobutyl-octadeca-2,4,13-trienamide, 1-(octadeca-2E,4E,12Z-trienoyl)-pyrrolidine, 1-(eicosa-2E,4E,15Z-trienyl)piperidine, 1-(eicosa-2E,4E,15Z-trienyl)pyrrolidine, (2E,4E,15Z)-N-isobutyl-eicosa-2,4,15-trienamide, and 1-(eicosa-2E,4E,14Z-trienoyl)-pyrrolidine were not yet reported in literature. Sensory studies by means of a modified half-tongue test revealed recognition thresholds ranging from 3.0 to 1150.2 nmol/cm² for pungency and from 520.6 to 2162.1 nmol/cm² for the tingling orosensation depending on their chemical structure.


Assuntos
Alcaloides/química , Benzodioxóis/química , Piper nigrum/química , Piperidinas/química , Extratos Vegetais/química , Alcamidas Poli-Insaturadas/química , Paladar , Adulto , Feminino , Humanos , Masculino , Estrutura Molecular , Adulto Jovem
16.
Maturitas ; 67(2): 144-50, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20594781

RESUMO

OBJECTIVE: To assess the effect, tolerability and acceptability of aged garlic extract as an adjunct treatment to existing antihypertensive medication in patients with treated, but uncontrolled, hypertension. DESIGN: A double-blind parallel randomised placebo-controlled trial involving 50 patients whose routine clinical records in general practice documented treated but uncontrolled hypertension. The active treatment group received four capsules of aged garlic extract (960 mg containing 2.4 mg S-allylcysteine) daily for 12 weeks, and the control group received matching placebos. The primary outcome measures were systolic and diastolic blood pressure at baseline, 4, 8 and 12 weeks, and change over time. We also assessed tolerability during the trial and acceptability at 12 weeks. RESULTS: In patients with uncontrolled hypertension (SBP ≥ 140 mmHg at baseline), systolic blood pressure was on average 10.2 ± 4.3 mmHg (p=0.03) lower in the garlic group compared with controls over the 12-week treatment period. Changes in blood pressure between the groups were not significant in patients with SBP<140 mmHg at baseline. Aged garlic extract was generally well tolerated and acceptability of trial treatment was high (92%). CONCLUSION: Our trial suggests that aged garlic extract is superior to placebo in lowering systolic blood pressure similarly to current first line medications in patients with treated but uncontrolled hypertension.


Assuntos
Alho , Hipertensão/tratamento farmacológico , Fitoterapia , Extratos Vegetais/uso terapêutico , Idoso , Pressão Sanguínea/efeitos dos fármacos , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Extratos Vegetais/farmacologia
17.
J Agric Food Chem ; 58(6): 3720-8, 2010 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-20180507

RESUMO

To investigate the influence of roasting time and temperature on the degradation of the bitter precursors 3-O-caffeoyl quinic acid (1), 5-O-caffeoyl quinic acid (2), and 4-O-caffeoyl quinic acid (3) as well as the formation of bitter tastants during coffee roasting, we prepared coffee brews from beans roasted either at 260 degrees C for 60-600 s or for 240 s at 190-280 degrees C. By means of HPLC-UV/vis and HPLC-MS/MS, bitter-tasting monocaffeoyl quinides (4-8), dicaffeoyl quinides (9-11), and 4-vinylcatechol oligomers (12-20) as well as the parent bitter precursors 1-3 were quantitatively analyzed in these brews. Quinides 4-11, exhibiting a coffee-typical bitter taste profile, were found to be preferentially formed under slight to medium roasting degrees and were observed to be degraded again to generate harsh bitter-tasting 4-vinylcatechol oligomers under more severe roasting conditions, thus matching the change in bitter taste quality observed by means of sensory studies. In addition, quantitative studies of the release profile of bitter compounds from ground coffee upon water percolation revealed that compounds 1-8 were rapidly extracted, dicaffeoyl quinides 9-11 were released rather slowly, and, in particular, compounds 12-17 were found to show strong retention to the ground coffee material. These data imply that the knowledge-based control of the roasting and/or the extraction conditions might be helpful in tailoring the bitter taste signature of coffee beverages.


Assuntos
Coffea/química , Café/química , Manipulação de Alimentos/métodos , Paladar , Temperatura Alta , Humanos
18.
J Agric Food Chem ; 58(3): 1976-85, 2010 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-20070100

RESUMO

As the consumption of coffee beverages sometimes is reported to cause gastric irritation, for which an increased stomach acid secretion is one of the promoting factors, different processing technologies such as steam-treatment have been developed to reduce putative stomach irritating compounds. There is evidence-based data neither on the effect of detailed processing variations nor on individual coffee components affecting the proton secretory activity (PSA). This work aimed at developing a screening model suitable for investigating the effects of commercial coffee beverages and components thereof on human parietal cells. Human gastric cancer cells (HGT-1) were treated with reconstituted freeze-dried coffee beverages prepared from customary coffee products such as regular coffee (RC, n = 4), mild bean coffee (MBC, n = 5), stomach friendly coffee (SFC, n = 4), and SFC decaffeinated (SFCD, n = 3). PSA was analyzed by flow cytometry using the pH-sensitive dye SNARF-AM. Treatment of the cells with MBC did not result in a PSA different from RC treatment (p

Assuntos
Café/química , Ácido Gástrico/metabolismo , Mucosa Gástrica/metabolismo , Estômago/química , Animais , Linhagem Celular Tumoral , Coffea/química , Humanos , Concentração de Íons de Hidrogênio , Modelos Biológicos
19.
BMC Complement Altern Med ; 9: 22, 2009 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-19583878

RESUMO

BACKGROUND: Flavanol-rich chocolate and lycopene-rich tomato extract have attracted interest as potential alternative treatment options for hypertension, a known risk factor for cardiovascular morbidity and mortality. Treatment of prehypertension (SBP 120-139/DBP 80-89 mmHg) may forestall progression to hypertension. However, there has been only limited research into non-pharmacological treatment options for prehypertension. We investigated the effect of dark chocolate or tomato extract on blood pressure, and their acceptability as an ongoing treatment option in a prehypertensive population. METHODS: Our trial consisted of two phases: a randomised controlled three-group-parallel trial over 12 weeks (phase 1) followed by a crossover of the two active treatment arms over an additional 12-week period (phase 2). Group 1 received a 50 g daily dose of dark chocolate with 70% cocoa containing 750 mg polyphenols, group 2 were allocated one tomato extract capsule containing 15 mg lycopene per day, and group 3 received one placebo capsule daily over 8 weeks followed by a 4-week washout period. In phase 2 the active treatment groups were crossed over to receive the alternative treatment. Median blood pressure, weight, and abdominal circumference were measured 4-weekly, and other characteristics including physical activity, general health, energy, mood, and acceptability of treatment were assessed by questionnaire at 0, 8 and 20 weeks. We analysed changes over time using a linear mixed model, and one time point differences using Kruskal-Wallis, Fisher's-Exact, or t-tests. RESULTS: Thirty-six prehypertensive healthy adult volunteers completed the 6-month trial. Blood pressure changes over time within groups and between groups were not significant and independent of treatment. Weight and other characteristics did not change significantly during the trial. However, a marked difference in acceptability between the two treatment forms (chocolate or capsule) was revealed (p < 0.0001). Half of the participants allocated to the chocolate treatment found it hard to eat 50 g of dark chocolate every day and 20% considered it an unacceptable long-term treatment option, whereas all participants found it easy and acceptable to take a capsule each day for blood pressure. CONCLUSION: Our study did not find a blood pressure lowering effect of dark chocolate or tomato extract in a prehypertensive population. Practicability of chocolate as a long-term treatment option may be limited. TRIAL REGISTRATION: http://www.anzctr.org.au Identifier: ACTRN12609000047291.


Assuntos
Anti-Hipertensivos/uso terapêutico , Cacau , Hipertensão/prevenção & controle , Fitoterapia , Extratos Vegetais/uso terapêutico , Preparações de Plantas/uso terapêutico , Solanum lycopersicum , Adulto , Idoso , Carotenoides/uso terapêutico , Estudos Cross-Over , Flavonoides/uso terapêutico , Humanos , Licopeno , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde , Fenóis/uso terapêutico , Polifenóis
20.
J Agric Food Chem ; 56(20): 9581-5, 2008 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-18817412

RESUMO

Recent investigations on the bitterness of coffee as well as 5- O-caffeoyl quinic acid roasting mixtures indicated the existence of another, yet unknown, bitter lactone besides the previously identified bitter compounds 5- O-caffeoyl- muco-gamma-quinide, 3- O-caffeoyl-gamma-quinide, 4- O-caffeoyl- muco-gamma-quinide, 5- O-caffeoyl- epi-delta-quinide, and 4- O-caffeoyl-gamma-quinide. In the present study, this orphan bitter lactone was isolated from the reaction products generated by dry heating of 5- O-caffeoylquinic acid model, and its structure was determined as the previously unreported 3- O-caffeoyl- epi-gamma-quinide by means of liquid chromatography-mass spectrometry (LC-MS) and one-/two-dimensional NMR experiments. The occurrence of this bitter lactone, exhibiting a low bitter recognition threshold of 58 micromol/L, in coffee beverages could be confirmed by LC-MS/MS (negative electrospray ionization) operating in the multiple reaction monitoring mode.


Assuntos
Café/química , Lactonas/química , Cromatografia Líquida de Alta Pressão , Humanos , Espectroscopia de Ressonância Magnética , Ácido Quínico/química , Paladar , Limiar Gustativo
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