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1.
J Nutr ; 148(suppl_2): 1406S-1412S, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31505676

RESUMO

The Dietary Supplement Label Database (DSLD) is sponsored by the Office of Dietary Supplements (ODS) and the National Library of Medicine (NLM). It provides a searchable, free database of the contents of ∼65,000 supplement labels. A companion database of analytically verified product labels [the Dietary Supplement Ingredient Database (DSID)] was created by ODS, NLM, and the USDA. There are considerable challenges to populating both databases, but the DSID faces unique analytic chemistry challenges. This article describes the challenges to creating analytically verified marketplace surveys of dietary supplement (DS) product content claims for inclusion in public databases. Nutritionists and public health scientists require information on actual exposures to DS constituents because labeled content may not match labeled product content. Analytic verification of composition of DSs provides a link to actual exposure. A public database of analytically derived DS content was developed to provide more accurate estimates of dietary intake in population-based epidemiologic studies. The DSID has conducted surveys of several types of vitamin- and mineral-containing DSs. Results showing label content claims as analytically derived values are available in the current DSID. A recent pilot project explored the feasibility of adding botanical DS products to the DSID. Candidates for future botanical DSID studies will be based on sales volume, potential public health impacts, and the availability of validated analytic methods and reference materials. Databases like DSID and the DSLD are essential for researchers and clinicians to evaluate dietary ingredient intakes in population-based epidemiologic studies. Together, these databases provide a picture of the DS marketplace. The DSID provides an analytic survey of marketed DSs. However, selection of future botanical supplements for DSID evaluation involves analytic challenges. Even when appropriate resources are available, method selection and data evaluation are resource- and time-consuming.


Assuntos
Bases de Dados Factuais , Suplementos Nutricionais/análise , Suplementos Nutricionais/efeitos adversos , Suplementos Nutricionais/normas , Rotulagem de Alimentos , Humanos , Laboratórios , Minerais/análise , Minerais/normas , National Institutes of Health (U.S.) , National Library of Medicine (U.S.) , Saúde Pública , Padrões de Referência , Chá/química , Chá/normas , Estados Unidos , United States Department of Agriculture , Vitaminas/análise , Vitaminas/normas
2.
J Nutr ; 148(suppl_2): 1413S-1421S, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31505677

RESUMO

OBJECTIVE: We describe the purpose of the Dietary Supplement Ingredient Database (DSID), the statistical methodology underlying online calculators of analytically verified supplement content estimates, and the application and significance of DSID label adjustments in nutritional epidemiology. BACKGROUND AND HISTORY: During dietary supplement (DS) manufacturing, many ingredients are added at higher than declared label amounts, but overages are not standardized among manufacturers. As a result, researchers may underestimate nutrient intakes from DSs. The DSID provides statistical tools on the basis of the results of chemical analysis to convert label claims into analytically predicted ingredient amounts. These adjustments to labels are linked to DS products reported in NHANES. RATIONALE: Tables summarizing the numbers of NHANES DS products with ingredient overages and below label content show the importance of DSID adjustments to labels for accurate intake calculations. RECENT DEVELOPMENTS: We show the differences between analytically based estimates and labeled content for vitamin D, calcium, iodine, caffeine, and omega-3 (n-3) fatty acids and their potential impact on the accuracy of intake assessments in large surveys. Analytical overages >20% of label levels are predicted for several nutrients in 50-99% of multivitamin-mineral products (MVMs) reported in NHANES: for iodine and selenium in adult MVMs, for iodine and vitamins D and E in children's MVMs, and for iodine, chromium, and potassium in nonprescription prenatal MVMs. Predicted overages of 10-20% for calcium can be applied to most MVMs and overages >10% for folic acid in the vast majority of adult and children's MVMs. FUTURE DIRECTIONS: DSID studies are currently evaluating ingredient levels in prescription prenatal MVMs and levels of constituents in botanical DSs. CONCLUSIONS: We estimate that the majority of MVM products reported in NHANES have significant overages for several ingredients. It is important to account for nonlabeled additional nutrient exposure from DSs to better evaluate nutritional status in the United States.


Assuntos
Bases de Dados Factuais , Suplementos Nutricionais/análise , Suplementos Nutricionais/normas , Rotulagem de Alimentos/normas , Humanos , Laboratórios , Minerais/administração & dosagem , Minerais/análise , Minerais/normas , Inquéritos Nutricionais , Controle de Qualidade , Estados Unidos , Vitaminas/administração & dosagem , Vitaminas/análise , Vitaminas/normas
3.
J Nutr ; 148(Suppl 2): 1428S-1435S, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-31249427

RESUMO

Objective: To describe the history, key features, recent enhancements, and common applications of the Dietary Supplement Label Database (DSLD). Background and History: Although many Americans use dietary supplements, databases of dietary supplements sold in the United States have not been widely available. The DSLD, an easily accessible public-use database was created in 2008 to provide information on dietary supplement composition for use by researchers and consumers. Rationale: Accessing current information easily and quickly is crucial for documenting exposures to dietary supplements because they contain nutrients and other bioactive ingredients that may have beneficial or adverse effects on human health. This manuscript details recent developments with the DSLD to achieve this goal and provides examples of how the DSLD has been used. Recent Developments: With periodic updates to track changes in product composition and capture new products entering the market, the DSLD currently contains more than 71,000 dietary supplement labels. Following usability testing with consumer and researcher user groups completed in 2016, improvements to the DSLD interface were made. As of 2017, both a desktop and mobile device version are now available. Since its inception in 2008, the use of the DSLD has included research, exposure monitoring, and other purposes by users in the public and private sectors. Future Directions: Further refinement of the user interface and search features to facilitate ease of use for stakeholders is planned. Conclusions: The DSLD can be used to track changes in product composition and capture new products entering the market. With over 71,000 DS labels it is a unique resource that policymakers, researchers, clinicians, and consumers may find valuable for multiple applications.


Assuntos
Comércio , Bases de Dados Factuais , Suplementos Nutricionais , Disseminação de Informação , Rotulagem de Produtos , Humanos , Estados Unidos
4.
Phytochem Anal ; 29(6): 613-626, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29968391

RESUMO

INTRODUCTION: Pro-toxic dehydropyrrolizidine alkaloids are associated with liver disease in humans. The potential for long-term, low-level or intermittent exposures to cause or contribute to chronically-developing diseases is of international concern. Eupatorium perfoliatum is a medicinal herb referred to as boneset. While the presence of dehydropyrrolizidine alkaloids in some Eupatorium species is well-established, reports on Eupatorium perfoliatum are scant and contradictory. OBJECTIVE: To investigate the presence of dehydropyrrolizidine alkaloids in a survey of boneset samples and related alcoholic tinctures, and hot water infusions and decoctions. METHODS: Methanol, hot water or aqueous ethanol extracts of Eupatorium perfoliatum and three closely-related species were subjected to HPLC-ESI(+)MS and MS/MS analysis using three complementary column methods. Dehydropyrrolizidine alkaloids were identified from their MS data and comparison with standards. RESULTS: Forty-nine samples of Eupatorium perfoliatum were shown to contain dehydropyrrolizidine alkaloids (0.0002-0.07% w/w), the majority dominated by lycopsamine and intermedine, their N-oxides and acetylated derivatives. Alcoholic tinctures and hot water infusions and decoctions had high concentrations of the alkaloids. Different chemotypes, hybridisation or contamination of some Eupatorium perfoliatum samples with related species were suggested by the co-presence of retronecine- and heliotridine-based alkaloids. CONCLUSIONS: Sampling issues, low and high alkaloid chemotypes of Eupatorium perfoliatum or interspecies hybridization could cause the wide variation in dehydropyrrolizidine alkaloid concentrations or the different profiles observed. Concerns associated with dehydropyrrolizidine alkaloids provide a compelling reason for preclusive caution until further research can better define the toxicity and carcinogenicity of the dehydropyrrolizidine alkaloid content of Eupatorium perfoliatum. [Correction added on 12 July 2018, after first online publication: The 'Conclusions' section in the abstract has been added.].


Assuntos
Eupatorium/química , Alcaloides de Pirrolizidina/toxicidade , Eupatorium/genética , Eupatorium/metabolismo , Hibridização Genética , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/toxicidade , Alcaloides de Pirrolizidina/química , Especificidade da Espécie , Espectrometria de Massas em Tandem
5.
Anal Chem ; 89(9): 4907-4913, 2017 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-28375002

RESUMO

The National Institute of Standards and Technology (NIST) has developed Standard Reference Material (SRM) 972a Vitamin D Metabolites in Frozen Human Serum as a replacement for SRM 972, which is no longer available. SRM 972a was developed in collaboration with the National Institutes of Health's Office of Dietary Supplements. In contrast to the previous reference material, three of the four levels of SRM 972a are composed of unmodified human serum. This SRM has certified and reference values for the following 25-hydroxyvitamin D [25(OH)D] species: 25(OH)D2, 25(OH)D3, and 3-epi-25(OH)D3. The value assignment and certification process included three isotope-dilution mass spectrometry approaches, with measurements performed at NIST and at the Centers for Disease Control and Prevention (CDC). The value assignment methods employed have been modified from those utilized for the previous SRM, and all three approaches now incorporate chromatographic resolution of the stereoisomers, 25(OH)D3 and 3-epi-25(OH)D3.


Assuntos
25-Hidroxivitamina D 2/sangue , Calcifediol/sangue , Cromatografia Líquida/normas , Espectrometria de Massas/normas , 25-Hidroxivitamina D 2/normas , Calcifediol/química , Calcifediol/normas , Humanos , Padrões de Referência , Valores de Referência , Estereoisomerismo , Estados Unidos , United States Government Agencies
6.
Phytochem Anal ; 27(5): 257-76, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27432636

RESUMO

INTRODUCTION: Within the Apocynoideae (Apocynaceae) pro-toxic dehydropyrrolizidine alkaloids have been reported only in Echiteae. However, attraction of pyrrolizidine alkaloid-pharmacophagous insects suggested their presence in Alafia cf. caudata Stapf (Nerieae: Alafiinae) and Amphineurion marginatum (Roxb.) D.J. Middleton (Apocyneae: Amphineuriinae), both used as medicinal plants. OBJECTIVE: To confirm the presence of dehydropyrrolizidine alkaloids in Alafia cf. caudata and Amphineurion marginatum and identify their structures. METHODS: Methanol extracts of air-dried roots, stems and leaves of non-flowering plants were analysed using HPLC-ESI(+)MS and MS/MS or collision-induced dissociation MS in low and/or high resolution modes. Pyrrolizidine alkaloids were tentatively identified based on the mass spectrometry data. Solid phase extraction combined with semi-preparative HPLC were used to isolate major alkaloids. Structures were elucidated using NMR spectroscopy. RESULTS: Monoesters of retronecine with senecioic, hydroxysenecioic or syringic acids were identified in roots of Alafia cf. caudata. Two unprecedented 10-membered macrocyclic dehydropyrrolizidine alkaloid diesters were isolated from roots of Amphineurion marginatum. Pyrrolizidine alkaloids were detected in root and leaf material of Alafia cf. caudata at 0.34 and 0.01% dry weight (DW), and 0.13, 0.02 and 0.09% DW in root, leaf and stem material of Amphineurion marginatum. CONCLUSIONS: The presence of pro-toxic dehydropyrrolizidine alkaloids suggests that medical preparations of these plants pose potential health risks to consumers. Dehydropyrrolizidine alkaloids are evidently more widespread in Apocynoideae than previously assumed, and it would seem rewarding to study other members of this family for the presence of pyrrolizidines, dehydropyrrolizidines and dihydropyrrolizines. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Alcaloides/isolamento & purificação , Apocynaceae/química , Plantas Medicinais , Pirróis/isolamento & purificação , Alcaloides/química , Resinas de Troca de Cátion , Cromatografia Líquida de Alta Pressão , Ésteres , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Pirróis/química , Extração em Fase Sólida
9.
J AOAC Int ; 97(6): 1503-13, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25372663

RESUMO

The most commonly used chondroitin sulfate (CS) assay method is cetylpyridinium chloride (CPC) titration. Cellulose acetate membrane electrophoresis (CAME) is the technique used for detection of impurities in the U.S. Pharmacopeia's CS monograph. Because CPC titration is a relatively nonspecific quantitative technique, the apparent amount of CS as determined by CPC titration alone may not reflect the true amount of CS due to possible interference with the CPC assay by impurities that contain CPC titratable functional groups. When CAME is used in conjunction with CPC titration, certain non-CS and adulterants can be visualized and estimated, and a true value for CS can be assigned once the presence of these non-CS impurities has been ruled out. This study examines conjunct application of CPC and CAME in ascertaining CS assay and purity in the presence of certain adulterants. These include propylene glycol alginate sulfate sodium, known in commerce as alginic sodium diester (ASD), and Zero One (Z1), a water-soluble agent newly reported in the CS marketplace and subsequently identified as sodium hexametaphosphate. ASD, Z1, and CS are similar in physical appearance and solubility in water and ethanol. They are also titratable anions and form ionic pairs with CPC, therefore interfering with the CPC titration assay for CS CAME separates these adulterants from each other and from CS by differences in their electrophoretic mobility. CAME is able to detect these impurities in CS at levels as low as 0.66% by weight. Although it is recommended that a method for detecting impurities (e.g., CAME) be used in cormbination with relatively nonspecific assay methods such as CPC titration, this is seldom done in practice. Assay results for CS derived fromn CPC titration may, therefore, be misleading, leaving the CS supply chain vulnerable to adulteration. In this study, the authors investigated ASD and Z1 adulteration of CS and developed an electrophoretic separation of these adulterants in CS and procedures to isolate ASD from CS matrixes containing these adulterants. The authors describe in this paper utilization of an orthogonal approach to establish the identity of Z1 as sodium hexametaphosphate and to confirm the identity of ASD, including ethanol fractionation, FTIR spectroscopy, differential scanning calorimetry, and NMR spectroscopy. The authors suggest that CAME is a cost-effective and easy to use methodfor detecting certain impurities in CS raw ingredients and recommend that CPC and CAME be used in combination by QC laboratories as a means of effectively deterring the practice of adulterating CS raw materials with the known adulterants ASD and Z1 and/or other non-chondroitin substances that can be separated from CSby CAME and that exhibit CPC titration behavior similar to CS.


Assuntos
Alginatos/isolamento & purificação , Cetilpiridínio/química , Sulfatos de Condroitina/química , Eletroforese em Acetato de Celulose/métodos , Fosfatos/isolamento & purificação , Contaminação de Medicamentos , Ácido Glucurônico/isolamento & purificação , Ácidos Hexurônicos/isolamento & purificação , Titulometria
10.
Phytochem Anal ; 25(5): 429-38, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24816769

RESUMO

INTRODUCTION: The diversity of structure and, particularly, stereochemical variation of the dehydropyrrolizidine alkaloids can present challenges for analysis and the isolation of pure compounds for the preparation of analytical standards and for toxicology studies. OBJECTIVE: To investigate methods for the separation of gram-scale quantities of the epimeric dehydropyrrolizidine alkaloids lycopsamine and intermedine and to compare their NMR spectroscopic data with those of their heliotridine-based analogues echinatine and rinderine. METHODS: Lycopsamine and intermedine were extracted, predominantly as their N-oxides and along with their acetylated derivatives, from commercial samples of comfrey (Symphytum officinale) root. Alkaloid enrichment involved liquid-liquid partitioning of the crude methanol extract between dilute aqueous acid and n-butanol, reduction of N-oxides and subsequent continuous liquid-liquid extraction of free base alkaloids into CHCl3 . The alkaloid-rich fraction was further subjected to semi-automated flash chromatography using boronated soda glass beads or boronated quartz sand. RESULTS: Boronated soda glass beads (or quartz sand) chromatography adapted to a Biotage Isolera Flash Chromatography System enabled large-scale separation (at least up to 1-2 g quantities) of lycopsamine and intermedine. The structures were confirmed using one- and two-dimensional (1) H- and (13) C-NMR spectroscopy. Examination of the NMR data for lycopsamine, intermedine and their heliotridine-based analogues echinatine and rinderine allowed for some amendments of literature data and provided useful comparisons for determining relative configurations in monoester dehydropyrrolizidine alkaloids. A similar NMR comparison of lycopsamine and intermedine with their N-oxides showed the effects of N-oxidation on some key chemical shifts. A levorotatory shift in specific rotation from +3.29° to -1.5° was observed for lycopsamine when dissolved in ethanol or methanol respectively. CONCLUSION: A semi-automated flash chromatographic process using boronated soda glass beads was standardised and confirmed as a useful, larger scale preparative approach for separating the epimers lycopsamine and intermedine. The useful NMR correlations to stereochemical arrangements within this specific class of dehydropyrrolizidine alkaloid cannot be confidently extrapolated to other similar dehydropyrrolizidine alkaloids. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.


Assuntos
Fracionamento Químico/métodos , Alcaloides de Pirrolizidina/química , Automação , Confrei/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Raízes de Plantas
11.
Anal Bioanal Chem ; 405(13): 4531-8, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23371533

RESUMO

As part of a collaboration with the National Institutes of Health's Office of Dietary Supplements and the Food and Drug Administration's Center for Drug Evaluation and Research, the National Institute of Standards and Technology has developed Standard Reference Material (SRM) 3274 Botanical Oils Containing Omega-3 and Omega-6 Fatty Acids and SRM 3275 Omega-3 and Omega-6 Fatty Acids in Fish Oil. SRM 3274 consists of one ampoule of each of four seed oils (3274-1 Borage (Borago officinalis), 3274-2 Evening Primrose (Oenothera biennis), 3274-3 Flax (Linium usitatissimum), and 3274-4 Perilla (Perilla frutescens)), and SRM 3275 consists of two ampoules of each of three fish oils (3275-1 a concentrate high in docosahexaenoic acid, 3275-2 an anchovy oil high in docosahexaenoic acid and eicosapentaenoic acid, and 3275-3 a concentrate containing 60% long-chain omega-3 fatty acids). Each oil has certified and reference mass fraction values for up to 20 fatty acids. The fatty acid mass fraction values are based on results from analyses using gas chromatography with flame ionization detection (GC-FID) and mass spectrometry (GC/MS). These SRMs will complement other reference materials currently available with mass fractions for similar analytes and are part of a series of SRMs being developed for dietary supplements.


Assuntos
Suplementos Nutricionais/normas , Ácidos Docosa-Hexaenoicos/normas , Ácido Eicosapentaenoico/normas , Óleos de Peixe/normas , Óleos de Plantas/normas , Cromatografia Gasosa , Suplementos Nutricionais/análise , Ácidos Docosa-Hexaenoicos/isolamento & purificação , Ácido Eicosapentaenoico/isolamento & purificação , Óleos de Peixe/química , Ionização de Chama , Humanos , Óleos de Plantas/química , Padrões de Referência , Valores de Referência
12.
J AOAC Int ; 96(6): 1281-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24645505

RESUMO

Standard Reference Material 3280 Multivitamin/ Multielement Tablets was issued by the National Institute of Standards and Technology in 2009, and has certified and reference mass fraction values for 13 vitamins, 26 elements, and two carotenoids. Elements were measured using two or more analytical methods at NIST with additional data contributed by collaborating laboratories. This reference material is expected to serve a dual purpose: to provide quality assurance in support of a database of dietary supplement products and to provide a means for analysts, dietary supplement manufacturers, and researchers to assess the appropriateness and validity of their analytical methods and the accuracy of their results.


Assuntos
Química Farmacêutica/normas , Suplementos Nutricionais/análise , Suplementos Nutricionais/normas , Vitaminas/análise , Carotenoides/análise , Química Farmacêutica/métodos , Controle de Qualidade , Padrões de Referência , Reprodutibilidade dos Testes , Comprimidos , Estados Unidos , Vitaminas/química
13.
Phytochem Anal ; 24(3): 201-12, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23070903

RESUMO

INTRODUCTION: A livestock poisoning outbreak near Kingman, Arizona, USA, potentially linked to dehydropyrrolizidine alkaloids, prompted an evaluation of some local plants for the presence of these hepatotoxic alkaloids. OBJECTIVE: To qualitatively and quantitatively examine two species of Cryptantha, a Boraginaceous genus previously shown to produce potentially toxic pyrrolizidine alkaloids, collected from the vicinity of Kingman, Arizona. METHOD: Plant extracts were analysed using HPLC-electrospray ionisation (+)-MS and MS/MS to determine the presence of dehydropyrrolizidine alkaloid esters. Identities were confirmed by comparison of chromatographic and MS data with authenticated standards and, in the case of the previously undescribed alkaloids, using one- and two-dimensional NMR spectroscopy and high-resolution mass measurement. RESULTS: Cryptantha inequata and C. utahensis were shown to produce retronecine-based dehydropyrrolizidine alkaloids at approximately 0.05% and 0.09% w/w respectively. Cryptantha inequata produced mainly echimidine, acetylechimidine and echiuplatine; dehydropyrrolizidine alkaloids that were previously associated with Echium plantagineum. The previously undescribed structure of echiuplatine was elucidated as an amphoteric, open chain diester with angelic acid and 3-hydroxy-3-methylglutaric acid. Along with lycopsamine, intermedine and dihydroxyechiumine, C. utahensis produced cryptanthine, a previously undescribed open chain diester alkaloid esterified with angelic acid and 2,3-dihydroxy-2-methylbutanoic acid. All pyrrolizidine alkaloids detected were present in the plants mainly as their N-oxides. CONCLUSION: The retronecine-based alkaloids detected in both Cryptantha species herein investigated aligns them within the Krynitzkia subgenus. The dehydropyrrolizidine alkaloids detected are expected to be toxic but the low levels in the plants potentially mitigate the risk. The identification of the amphoteric echiuplatine provides a cautionary note with respect to the analysis of total dehydropyrrolizidine alkaloid content.


Assuntos
Boraginaceae/química , Alcaloides de Pirrolizidina/análise , Alcaloides de Pirrolizidina/química , Arizona , Espectroscopia de Ressonância Magnética , Meglutol/análise , Estrutura Molecular , Óxidos/química , Extratos Vegetais/análise , Extratos Vegetais/química , Plantas Tóxicas/intoxicação , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem
14.
Anal Chem ; 84(2): 956-62, 2012 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-22141317

RESUMO

The National Institute of Standards and Technology (NIST), in collaboration with the National Institutes of Health's Office of Dietary Supplements (NIH-ODS), has developed a Standard Reference Material (SRM) for the determination of 25-hydroxyvitamin D [25(OH)D] in serum. SRM 972 Vitamin D in Human Serum consists of four serum pools with different levels of vitamin D metabolites and has certified and reference values for 25(OH)D(2), 25(OH)D(3), and 3-epi-25(OH)D(3). Value assignment of this SRM was accomplished using a combination of three isotope-dilution mass spectrometry approaches, with measurements performed at NIST and at the Centers for Disease Control and Prevention (CDC). Chromatographic resolution of the 3-epimer of 25(OH)D(3) proved to be essential for accurate determination of the metabolites.


Assuntos
Vitamina D/análogos & derivados , Cromatografia Líquida , Humanos , Espectrometria de Massas , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Vitamina D/análise , Vitamina D/sangue , Vitamina D/normas
15.
J Nutr ; 142(6): 1175S-85S, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22551802

RESUMO

The Office of Dietary Supplements (ODS) at the NIH sponsored a workshop on May 12-13, 2011, to bring together representatives from various NIH institutes and centers as a first step in developing an NIH iodine research initiative. The workshop also provided an opportunity to identify research needs that would inform the dietary reference intakes for iodine, which were last revised in 2001. Iodine is required throughout the life cycle, but pregnant women and infants are the populations most at risk of deficiency, because iodine is required for normal brain development and growth. The CDC monitors iodine status of the population on a regular basis, but the status of the most vulnerable populations remains uncertain. The NIH funds very little investigator-initiated research relevant to iodine and human nutrition, but the ODS has worked for several years with a number of other U.S. government agencies to develop many of the resources needed to conduct iodine research of high quality (e.g., validated analytical methods and reference materials for multiple types of samples). Iodine experts, scientists from several U.S. government agencies, and NIH representatives met for 2 d to identify iodine research needs appropriate to the NIH mission.


Assuntos
Iodo/sangue , Iodo/deficiência , Pesquisa , Adolescente , Adulto , Canadá , Criança , Pré-Escolar , Feminino , Humanos , Hipotireoidismo/epidemiologia , Lactente , Recém-Nascido , Lactação , National Institutes of Health (U.S.) , Política Nutricional , Gravidez , Estados Unidos , Adulto Jovem
16.
J Nutr ; 141(2): 261-6, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21178089

RESUMO

Dietary supplement use has steadily increased over time since the 1970s; however, no current data exist for the U.S. population. Therefore, the purpose of this analysis was to estimate dietary supplement use using the NHANES 2003-2006, a nationally representative, cross-sectional survey. Dietary supplement use was analyzed for the U.S. population (≥1 y of age) by the DRI age groupings. Supplement use was measured through a questionnaire and was reported by 49% of the U.S. population (44% of males, 53% of females). Multivitamin-multimineral use was the most frequently reported dietary supplement (33%). The majority of people reported taking only 1 dietary supplement and did so on a daily basis. Dietary supplement use was lowest in obese adults and highest among non-Hispanic whites, older adults, and those with more than a high-school education. Between 28 and 30% reported using dietary supplements containing vitamins B-6, B-12, C, A, and E; 18-19% reported using iron, selenium, and chromium; and 26-27% reported using zinc- and magnesium-containing supplements. Botanical supplement use was more common in older than in younger age groups and was lowest in those aged 1-13 y but was reported by ~20% of adults. About one-half of the U.S. population and 70% of adults ≥ 71 y use dietary supplements; one-third use multivitamin-multimineral dietary supplements. Given the widespread use of supplements, data should be included with nutrient intakes from foods to correctly determine total nutrient exposure.


Assuntos
Suplementos Nutricionais/estatística & dados numéricos , Micronutrientes/administração & dosagem , Fitoterapia/estatística & dados numéricos , Adolescente , Adulto , Fatores Etários , Idoso , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Obesidade/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Fatores Socioeconômicos , Inquéritos e Questionários , Estados Unidos , Adulto Jovem
17.
J AOAC Int ; 94(5): 1400-10, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22165004

RESUMO

A method previously validated to determine caftaric acid, chlorogenic acid, cynarin, echinacoside, and cichoric acid in echinacea raw materials has been successfully applied to dry extract and liquid tincture products in response to North American consumer needs. Single-laboratory validation was used to assess the repeatability, accuracy, selectivity, LOD, LOQ, analyte stability (ruggedness), and linearity of the method, with emphasis on finished products. Repeatability precision for each phenolic compound was between 1.04 and 5.65% RSD, with HorRat values between 0.30 and 1.39 for raw and dry extract finished products. HorRat values for tinctures were between 0.09 and 1.10. Accuracy of the method was determined through spike recovery studies. Recovery of each compound from raw material negative control (ginseng) was between 90 and 114%, while recovery from the finished product negative control (maltodextrin and magnesium stearate) was between 97 and 103%. A study was conducted to determine if cichoric acid, a major phenolic component of Echinacea purpurea (L.) Moench and E. angustifolia DC, degrades during sample preparation (extraction) and HPLC analysis. No significant degradation was observed over an extended testing period using the validated method.


Assuntos
Echinacea/química , Fenóis/análise , Algoritmos , Ácido Ascórbico/análise , Ácidos Cafeicos/química , Calibragem , Cápsulas , Ácido Clorogênico/análise , Cromatografia Líquida de Alta Pressão , Cinamatos/análise , Flores/química , Indicadores e Reagentes , Extratos Vegetais/análise , Folhas de Planta/química , Raízes de Plantas/química , Caules de Planta/química , Padrões de Referência , Reprodutibilidade dos Testes , Soluções/química , Solventes , Espectrofotometria Ultravioleta , Succinatos/química , Zinco/análise
18.
J AOAC Int ; 94(3): 803-14, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21797008

RESUMO

The National Institute of Standards and Technology (NIST) has established a Dietary Supplement Laboratory Quality Assurance Program (DSQAP) in collaboration with the National Institutes of Health Office of Dietary Supplements. Program participants measure concentrations of active and/or marker compounds as well as nutritional and toxic elements in food and dietary supplements distributed by NIST. Data are compiled at NIST, where they are analyzed for accuracy relative to reference values and concordance among the participants. Performance reports and certificates of completion are provided to participants, which can be used to demonstrate compliance with current Good Manufacturing Practices as promulgated by the U.S. Food and Drug Administration. The DSQAP has conducted five exercises to date, with total participation including more than 75 different laboratories and many more individual analysts.


Assuntos
Suplementos Nutricionais/análise , Suplementos Nutricionais/normas , Laboratórios/normas , Preparações de Plantas/química , Vitaminas/química , Ácidos Graxos/química , Ácidos Graxos/normas , Análise de Alimentos/normas , Preparações de Plantas/normas , Controle de Qualidade , Estados Unidos
19.
Phytochem Anal ; 22(6): 532-40, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21433162

RESUMO

INTRODUCTION: A previous investigation of pyrrolizidine alkaloids produced by nine species of Cryptantha identified at least two chemotypes within the genus. Other research has postulated that pyrrolizidine-N-oxide concentrations increase as the growing conditions become harsher, particularly with respect to water availability. Cryptantha crassipes is an endangered plant with a very limited distribution range within a dry, harsh Texan ecosystem. OBJECTIVE: To determine the pyrrolizidine alkaloid (and their N-oxides) profile and concentrations in Cryptantha crassipes. METHODOLOGY: Methanolic extracts of Cryptantha crassipes were partitioned into dilute sulphuric acid and the alkaloids concentrated using strong cation exchange, solid-phase extraction columns. Extracts were analysed using reversed-phase high-pressure liquid chromatography coupled to electrospray ionisation ion trap mass spectrometry. RESULTS: The N-oxides of lycopsamine and intermedine were the major pyrrolizidine alkaloids detected in Cryptantha crassipes. Smaller to trace amounts of other pyrrolizidine alkaloids observed were: the 7- and 3'-acetylated derivatives and the 1,2-dihydro analogs of lycopsamine-N-oxide and/or intermedine-N-oxide; a pair of unidentified N-oxides, isobaric with lycopsamine-N-oxide; and the N-oxides of leptanthine, echimiplatine, amabiline, echiumine and dihydroechiumine. Only trace amounts, if any, of the parent free base pyrrolizidine alkaloids were detected. The concentration of pyrrolizidine alkaloids was estimated to be 3-5% of the dry weight of milled leaves, or 10-50 times the levels previously reported for similar chemotypes. CONCLUSIONS: The high levels of the N-oxides of lycopsamine and intermedine establish the genus chemotype of the endangered Cryptantha crassipes and support earlier data linking high levels of N-oxides to dry, harsh growing conditions.


Assuntos
Boraginaceae/química , Óxidos/análise , Alcaloides de Pirrolizidina/química , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Espécies em Perigo de Extinção , Índigo Carmim/química , Metanol/química , Óxidos/química , Extratos Vegetais/análise , Extratos Vegetais/química , Folhas de Planta/química , Alcaloides de Pirrolizidina/análise , Extração em Fase Sólida , Espectrometria de Massas por Ionização por Electrospray , Ácidos Sulfúricos/química
20.
JAMA ; 306(12): 1344-51, 2011 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-21954478

RESUMO

CONTEXT: Saw palmetto fruit extracts are widely used for treating lower urinary tract symptoms attributed to benign prostatic hyperplasia (BPH); however, recent clinical trials have questioned their efficacy, at least at standard doses (320 mg/d). OBJECTIVE: To determine the effect of saw palmetto extract (Serenoa repens, from saw palmetto berries) at up to 3 times the standard dose on lower urinary tract symptoms attributed to BPH. DESIGN, SETTING, AND PARTICIPANTS: A double-blind, multicenter, placebo-controlled randomized trial at 11 North American clinical sites conducted between June 5, 2008, and October 10, 2010, of 369 men aged 45 years or older, with a peak urinary flow rate of at least 4 mL/s, an American Urological Association Symptom Index (AUASI) score of between 8 and 24 at 2 screening visits, and no exclusions. INTERVENTIONS: One, 2, and then 3 doses (320 mg/d) of saw palmetto extract or placebo, with dose increases at 24 and 48 weeks. MAIN OUTCOME MEASURES: Difference in AUASI score between baseline and 72 weeks. Secondary outcomes included measures of urinary bother, nocturia, peak uroflow, postvoid residual volume, prostate-specific antigen level, participants' global assessments, and indices of sexual function, continence, sleep quality, and prostatitis symptoms. RESULTS: Between baseline and 72 weeks, mean AUASI scores decreased from 14.42 to 12.22 points (-2.20 points; 95% CI, -3.04 to -1.36) [corrected]with saw palmetto extract and from 14.69 to 11.70 points (-2.99 points; 95% CI, -3.81 to -2.17) with placebo. The group mean difference in AUASI score change from baseline to 72 weeks between the saw palmetto extract and placebo groups was 0.79 points favoring placebo (upper bound of the 1-sided 95% CI most favorable to saw palmetto extract was 1.77 points, 1-sided P = .91). Saw palmetto extract was no more effective than placebo for any secondary outcome. No clearly attributable adverse effects were identified. CONCLUSION: Increasing doses of a saw palmetto fruit extract did not reduce lower urinary tract symptoms more than placebo. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00603304.


Assuntos
Antagonistas de Androgênios/administração & dosagem , Extratos Vegetais/administração & dosagem , Hiperplasia Prostática/complicações , Transtornos Urinários/tratamento farmacológico , Idoso , Relação Dose-Resposta a Droga , Método Duplo-Cego , Humanos , Masculino , Pessoa de Meia-Idade , Serenoa , Resultado do Tratamento , Transtornos Urinários/etiologia
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