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1.
Clin Nutr ; 40(1): 222-228, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32534950

RESUMO

Differences in vitamin and carotenoids content of human milk (HM) produced for infants born at term and preterm is poorly understood. In this study, HM was collected weekly for four and two months post-partum for preterm and term groups, respectively. Nutrients of interest, from single full breast expressions were measured by liquid chromatography coupled with mass spectrometry. Microbiological assay was employed for vitamin B12. When compared at equivalent post-partum age, vitamins B1, B2, B6, and B9 were significantly higher in preterm than in term HM, but only during the first two weeks. No significant differences were observed for A, E, B3 and B12 between groups. Lycopene was the only carotenoid exhibiting a significant higher concentration in term than in preterm HM between weeks 1 and 4 post-partum. When compared at equivalent post-menstrual age, preterm milk was significantly higher for vitamins B1, B2, B3, B6 and B9 and lower levels of vitamins A, E, ß-carotene, ß-cryptoxanthin, lutein, zeaxanthin and lycopene compared to their term counterparts. These results suggest that preterm breastfed infants at term equivalent age may receive lower amounts of these micronutrients than breast-fed term neonates, possibly highlighting the need to supplement or fortify their nutritional intake with vitamins and carotenoids. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT #02052245.


Assuntos
Carotenoides/análise , Recém-Nascido Prematuro/crescimento & desenvolvimento , Leite Humano/química , Necessidades Nutricionais/fisiologia , Vitaminas/análise , Suplementos Nutricionais , Ingestão de Alimentos , Feminino , Alimentos Fortificados , Humanos , Fenômenos Fisiológicos da Nutrição do Lactente , Recém-Nascido , Masculino , Avaliação Nutricional , Estudos Prospectivos
2.
J AOAC Int ; 102(4): 1059-1068, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30786951

RESUMO

Background: Human milk is the optimal nutrition for all newborns in the first 6 months of life. In order to assess the nutritional needs of the breastfed infant, human milk is often characterized for multiple nutrients. Objective: To ensure that we minimize the volume of milk dedicated for research and optimize the number of nutrients characterized, we developed analytical methodologies for the determination of vitamins A (retinol), E (alpha and gamma tocopherol), K (phylloquinone and menaquinone-4), and five carotenoids (ß-carotene, lycopene, ß-cryptoxanthin, lutein, and zeaxanthin) using <1 mL human milk. Method: Vitamins E and K and carotenoids are simultaneously isolated from 750 µL milk by liquid-liquid extraction (LLE). Tocopherols and carotenoids are determined by normal-phase LC with fluorescence and ultraviolet detection respectively. Vitamin K is analyzed on the same extracts after resuspension and clean-up by reversed phase liquid chromatography coupled to tandem MS. The analysis of vitamin A involves saponification of 200 µL milk followed by LLE and determination by normal-phase LC with UV detection. Results: Full single-laboratory validation at four different concentration levels is presented. Recovery rates were within 90-105% in all except one case (retinol at 1.9 µg/mL, 88% recovery), with RSDs of repeatability and intermediate reproducibility below 10 and 15%, respectively for all the compounds. Conclusions and Highlights: To the best of best knowledge, this is the first report that allows for the characterization and quantification of vitamins A, E, and K and five carotenoids in <1 mL human milk.


Assuntos
Carotenoides/análise , Cromatografia de Fase Reversa/métodos , Leite Humano/química , Vitamina A/análise , Vitamina E/análise , Vitamina K/análise , Humanos , Reprodutibilidade dos Testes
3.
Artigo em Inglês | MEDLINE | ID: mdl-29665470

RESUMO

In the present manuscript, we describe a fully optimized and validated method suitable to analyse nine compounds (retinyl acetate, retinyl palmitate, retinol, α-tocopherol, α-tocopheryl acetate, cholecalciferol, ergocalciferol, phylloquinone, menaquinone-4) representing the major contributors to the fat-soluble vitamin activity of selected food products (infant formulas, adult nutritionals, infant cereals and mixed meals). Sample preparation involves direct solvent extraction using enzyme-assisted matrix disintegration and methanolic protein precipitation. Direct injection of the extract allows quantification of vitamins A, E and K in only 7 min, while vitamin D is determined after fast derivatization of the extract. Separation is achieved by supercritical fluid chromatography and detection performed by tandem mass spectrometry in positive Atmospheric Pressure Chemical Ionization mode. Results on a Standard Reference Material (SRM 1849a Infant/Adult Nutritional) were not statistically different from reference values. Full validation of the method showed excellent overall performance. Average recovery rate was between 90 and 110% for all vitamins and matrixes. The methodology shows enhanced safety and reduced cost as compared with previously published methods, together with potential for application to more complex matrixes. The full procedure can be easily applied in control laboratories dramatically increasing sample throughput and reducing solvent consumption.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Análise de Alimentos/métodos , Espectrometria de Massas/métodos , Vitaminas/análise , Alimentos Congelados/análise , Humanos , Lactente , Alimentos Infantis/análise , Modelos Lineares , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
4.
Mol Nutr Food Res ; 62(6): e1700613, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29368422

RESUMO

SCOPE: Micronutrients are in small amounts in foods, act in concert, and require variable amounts of time to see changes in health and risk for disease. These first principles are incorporated into an intervention study designed to develop new experimental strategies for setting target recommendations for food bioactives for populations and individuals. METHODS AND RESULTS: A 6-week multivitamin/mineral intervention is conducted in 9-13 year olds. Participants (136) are (i) their own control (n-of-1); (ii) monitored for compliance; (iii) measured for 36 circulating vitamin forms, 30 clinical, anthropometric, and food intake parameters at baseline, post intervention, and following a 6-week washout; and (iv) had their ancestry accounted for as modifier of vitamin baseline or response. The same intervention is repeated the following year (135 participants). Most vitamins respond positively and many clinical parameters change in directions consistent with improved metabolic health to the intervention. Baseline levels of any metabolite predict its own response to the intervention. Elastic net penalized regression models are identified, and significantly predict response to intervention on the basis of multiple vitamin/clinical baseline measures. CONCLUSIONS: The study design, computational methods, and results are a step toward developing recommendations for optimizing vitamin levels and health parameters for individuals.


Assuntos
Micronutrientes/administração & dosagem , Vitaminas/sangue , Adolescente , Criança , Dislipidemias/sangue , Comportamento Alimentar , Feminino , Humanos , Individualidade , Masculino
5.
Food Chem ; 197 Pt B: 1249-55, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26675864

RESUMO

A multi-residue method based on two different extraction procedures was developed and compared with liquid chromatography electrospray ionization tandem mass spectrometry analysis of eighteen water-soluble artificial colours including Tartrazine (E102), Chrysoine (E103), Quinoline Yellow (E104), Yellow 2G (E107), Sunset Yellow (E110), Azorubine (E122), Amaranth (E123), Ponceau 4R (E124), Erythrosine (E127), Red 2G (E128), Allura Red (E129), Patent Blue V (E131), Indigo Carmine (E132), Brilliant Blue (E133), Green S (E142), Fast Green (E143), Brilliant Black (E151), and Black 7984 (E152) in sugar and gummy confectionary, ice-cream, and chocolate sweets. Sample preparation included SPE clean-up and liquid-liquid extraction for ice-cream and chocolate sweets. Accuracy was evaluated by recovery experiments. Correlation between response and concentration was obtained with R(2)>0.98 for all but six colours. Limits of quantification were within the 10-50 µg/kg range for E129; 20-200 µg/kg for E152; 10-250 µg/kg for E103; 10-500 µg/kg for E102, E104, E107, E110, E122, E123, E124, E127, E128, E131, E133; 20-800 µg/kg for E132, 142, 151; and 10-1000 µg/kg for E143. CV for repeatability ranged from 4.0% to 51.0%, while the CV for intermediate reproducibility ranged from 5.8% to 41.4%. Finally, recoveries varied from 84.3% to 166.0%. Together, these demonstrate that the method has been validated for complex matrices and is, thus, fit-for-purpose.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Corantes de Alimentos/análise , Doces/análise , Limite de Detecção , Extração Líquido-Líquido , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
6.
J AOAC Int ; 88(5): 1404-12, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16385990

RESUMO

An interlaboratory study was performed to evaluate the effectiveness of a headspace gas chromatography (GC) method for the determination of 1,3-dichloro-propan-2-ol (1,3-DCP) in soy sauce and related products at levels above 5 ng/g. The test portion is mixed with an internal standard (d5-1,3-DCP) and ammonium sulfate in a sealed headspace vial. After achieving equilibrium, the headspace is sampled either by gas-tight syringe or solid-phase microextraction (SPME) and analyzed by GC with mass spectrometric detection. 1,3-DCP is detected in the selected-ion mode (monitoring m/z 79 and 81 for 1,3-DCP and m/z 82 for the deuterated internal standard) and quantified by measurement against standards. Test materials comprising soy, dark soy, mushroom soy, and teriyaki sauces, both spiked and naturally contaminated, were sent to 9 laboratories in Europe, Japan, and the United States; of these, 5 used SPME and 4 used syringe headspace analysis. Test portions were spiked at 5.0, 10.0, 20.0, 100.0, and 500.0 ng/g. The average recovery for spiked blank samples was 108% (ranging from 96-130%). Based on results for spiked samples (blind pairs at 5, 10, 20, 100, and 500 ng/g) as well as a naturally contaminated sample (split-level pair at 27 and 29 ng/g), the relative standard deviation for repeatability (RSDr) ranged from 2.9-23.2%. The relative standard deviation for reproducibility (RSDR) ranged from 20.9-35.3%, and HorRat values of between 1.0 and 1.6 were obtained.


Assuntos
Análise de Alimentos/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Alimentos de Soja/análise , alfa-Cloridrina/análogos & derivados , Calibragem/normas , Reprodutibilidade dos Testes , alfa-Cloridrina/análise
7.
J Chromatogr A ; 1035(1): 123-30, 2004 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-15117081

RESUMO

A quantitative method has been developed for the determination of trace levels (<50 microg/kg) of acrylamide in cereal-based foods. The method is based on extraction of acrylamide with water, acidification and purification with Carrez I and II solutions, followed by bromination of the acrylamide double bond. The reaction product (2,3-dibromopropionamide) is extracted with ethyl acetate/hexane (4:1, v/v), dried over sodium sulfate, and cleaned up through a Florisil column. The derivative is then converted to 2-bromopropenamide by dehydrobromination with triethylamine and analyzed by gas chromatography coupled to mass spectrometry (GC-MS), employing (13C3)acrylamide as internal standard. In-house validation data for commercial and experimental cereal products showed good precision of the method, with repeatability and intermediate reproducibility relative standard deviations below 10%. The limit of detection and limit of quantitation are estimated at 2 and 5 microg/kg, respectively, and recoveries of acrylamide from samples spiked at levels of 5-500 microg/kg ranged between 93 and 104% after correction of analyte loss by the internal standard. Finally, a comparative test organized with two independent laboratories provided additional confidence in the good performance of the method, particularly at very low concentration levels.


Assuntos
Acrilamida/análise , Grão Comestível/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Calibragem , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
8.
J Agric Food Chem ; 52(16): 5102-8, 2004 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-15291482

RESUMO

The formation of chloropropanols was investigated using model systems comprised of lipase, vegetable oil or fat, water, and sodium chloride. The results showed that measurable levels of the foodborne carcinogen 3-chloro-1,2-propanediol (3-MCPD) are formed in the presence of commercially available lipases of mammalian, vegetable, and fungal origins, incubated at temperatures of 40 degrees C. The highest yield of 3-MCPD was obtained in reaction mixtures containing lipase from Rhizopus oryzae, and all the lipases studied exhibited a high hydrolytic activity toward triglycerides from palm and peanut oil. In contrast, hydrolysis over time and the yield of 3-MCPD in olive and sunflower oils were significantly lower (up to 10-fold), possibly linked to the relatively lower amount (<18%) of saturated fatty acids in these oils. We provide here for the first time evidence that lipases are able to induce the formation of chloropropanols under model system conditions. However, the key intermediates and precise mechanistic aspects governing the formation of 3-MCPD in the presence of lipase still need to be elucidated.


Assuntos
Lipase/metabolismo , alfa-Cloridrina/metabolismo , Concentração de Íons de Hidrogênio , Hidrólise , Óleo de Palmeira , Óleo de Amendoim , Óleos de Plantas/metabolismo , Rhizopus/enzimologia , Triglicerídeos/metabolismo , Verduras/enzimologia
9.
J Agric Food Chem ; 58(13): 7510-9, 2010 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-20527950

RESUMO

Two multiresidue methods based on different extraction procedures have been developed and compared for the liquid chromatography electrospray ionization tandem mass spectrometry analysis of 17 mycotoxins including ochratoxin A, aflatoxins (B(1), B(2), G(1), and G(2)), zearalenone, fumonisins (B(1) and B(2)), T-2 toxin, HT-2 toxin, nivalenol, deoxynivalenol, 3- and 15-acetyldeoxynivalenol, fusarenon-X, diacetoxyscirpenol, and neosolaniol in cereal-based commodities. The extraction procedures considered were a QuEChERS-like method and one using accelerated solvent extraction (ASE). Both extraction procedures gave similar performances in terms of linearity (r(2) > 0.98) and precision (both RSD(r) and RSD(iR) < 20%). Trueness was evaluated through participation in four proficiency tests and by the analysis of two certified reference materials and one quality control material. Satisfactory Z scores (|Z| < 2) and trueness values (73-130%) were obtained by the proposed procedures. Limits of quantification were similar by both methods and were within the 1.0-2.0 microg/kg range for aflatoxins, 0.5 microg/kg for ochratoxin A, and the 5-100 microg/kg range for all other mycotoxins tested. The QuEChERS-like method was found to be easier to handle and allowed a higher sample throughput as compared to the ASE method.


Assuntos
Cromatografia Líquida/métodos , Grão Comestível/química , Contaminação de Alimentos/análise , Micotoxinas/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Sensibilidade e Especificidade
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