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1.
Biol Trace Elem Res ; 176(2): 429-441, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27637916

RESUMO

The aim of this study was to evaluate the elemental composition of black tea samples and their infusions in view of their geographical origin. In total, 14 elements were analyzed, 13 (Ca, K, Mg, Na, Mn, Fe, Zn, Cu, Cr, Ni, Co, Cd, and Pb) by flame atomic absorption spectrometry, and P by UV-Vis spectrometry, after mineralization of samples. It was found that K was the most abundant macroelement in the analyzed samples, whereas among microelements, the highest concentration was found for Mn. Based on the obtained data, the percentage of elements leached into the infusions as well as the daily elemental intake from tea were calculated. The daily intake from tea was compared to the recommended daily allowances (RDAs), and the highest percentages of the RDAs were found for Mn (15 %) and Co (10 %). To study the relations between elemental composition and country of origin of samples, factor analysis and cluster analysis were applied. These multivariate techniques proved to be efficient tools able to differentiate samples according to their provenance as well as plantation within the common regions.


Assuntos
Geografia , Chá/química , Oligoelementos/análise , Monitoramento Ambiental , Espectrofotometria Atômica , Espectrofotometria Ultravioleta
2.
Biol Trace Elem Res ; 174(1): 240-250, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27038620

RESUMO

This study concerns application of flame atomic absorption spectrometry (FAAS) in assessment of macro- and microelement and toxic metal levels (Mg, Ca, K, Na, Mn, Cu, Fe, Zn, Cr, Ni, Co, Cd and Pb) in dark (Pu-erh) and fruit tea leaves and their infusions. Phosphorus was also determined in the form of phosphomolybdate by spectrophotometric method. The reliability of the method was checked using three certified reference materials. The results of analysis were in agreement with the certified values, with analytical recovery ranging from 86 to 113 %. Significant correlations (p < 0.001) were found between concentrations of P, Zn, K, Ni, Fe, Co, Cr, and Pb in Pu-erh tea, whereas in fruit tea, such interdependences were found between Mg, Fe, P, Ni, and Co. Kruskal-Wallis test results have related differences in Pu-erh tea quality as well as technological processing of fruit tea to their mineral composition. In order to characterize tea elemental content, chemometric techniques such as factor analysis (FA) and cluster analysis (CA) were used. Their application allowed on differentiation of samples in view of the fermentation type, technological processing, and overall quality.


Assuntos
Análise de Alimentos , Metais/análise , Chá/anatomia & histologia , Chás de Ervas/análise
3.
Environ Monit Assess ; 188(3): 183, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26899031

RESUMO

The present study measured the concentrations of toxic metals (Cd, Pb) and other elements (Ca, K, Mg, Na, P, Mn, Fe, Zn, Cu, Co, Cr, Ni) in tea leaves and their infusions. The total metal contents were determined by atomic absorption spectrometry. Phosphorus concentration was determined using an ultraviolet-visible spectrophotometer. Assessment of the mineral composition enabled determination of the leaching percentage and the risk of exceeding provisional tolerable weekly intake for Cd through daily tea consumption. The concentrations of bioelements were analyzed based on the recommended daily intake values for each. According to recently established standards, green tea was found to be a rich source of Mn. The average Pb and Cd levels in a 200-mL beverage were 0.002 and 0.003 mg, respectively. Indian teas had the highest percentage of Cd leaching (43.8%) and Chinese tea had the lowest (9.41%). Multivariate analysis techniques such as factor analysis and cluster analysis were used to differentiate samples according to geographical origin (China, India, or Japan). Potassium, P, Mn, Fe, Cu, Co, and Cd were effective descriptors for the identification of tea samples from China, India, and Japan.


Assuntos
Monitoramento Ambiental , Contaminação de Alimentos/análise , Metais/análise , Poluentes do Solo/análise , Chá/química , China , Contaminação de Alimentos/estatística & dados numéricos , Humanos , Índia , Japão , Metais Pesados/análise , Minerais/análise , Análise Multivariada , Espectrofotometria Atômica
4.
Rocz Panstw Zakl Hig ; 62(4): 413-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22435297

RESUMO

Contemporary sport requires a lot of effort from sportsmen, frequently exceeding their maximum physical and mental efficiency. Athletes often report poor dietary habits and reach for magnesium and vitamin B supplements to avoid dietary deficiencies. The aim of this study was to determine magnesium and vitamin B6 content in daily food rations of Polish athletes and to verify the justification of diet supplementation. Magnesium and vitamin B6 concentrations were determined in 62 collected and 12 reconstructed daily food rations of elite Polish runners. Flame atomic absorption spectrometry and HPLC methods were used for quantification of magnesium and vitamin B6, respectively. The analyzed female diets provided daily 256 +/- 111 mg of magnesium and 2.04 +/- 0.63 mg of vitamin B6 whereas male diets provided 284 +/- 58 mg of magnesium and 2.12 +/- 0.68 mg of vitamin B6. Computer analysis calculated 159-181% higher content o magnesium and vitamin B6 comparing to determined laboratory values. The results of this study indicate that in the analyzed daily food rations of athletes low magnesium intake was observed, thus diet supplementation with this mineral may be justified. Daily food rations fulfilled RDA for vitamin B6, thus supplementation with this vitamin was not justified.


Assuntos
Atletas/estatística & dados numéricos , Suplementos Nutricionais , Magnésio/administração & dosagem , Vitamina B 6/administração & dosagem , Adulto , Ingestão de Energia , Comportamento Alimentar , Feminino , Humanos , Masculino , Necessidades Nutricionais , Estado Nutricional , Polônia , Adulto Jovem
5.
Rocz Panstw Zakl Hig ; 59(2): 179-86, 2008.
Artigo em Polonês | MEDLINE | ID: mdl-18807916

RESUMO

Concentrations of Ca, P, Fe, Zn and Cu were determined in 30 different kinds of fresh vegetables available in sale. The contents of chemical elements (except phosphorus) were analysed, after dry mineralization, by flame atomic absorption spectrometry--AAS with deuterium background correction. The phosphorus was determined in the form of phosphormolybdate blue by spectrophotometric method. Reliability of the procedure was checked by the analysis of certified reference materials. The average contents (mg/100 g) of minerals in vegetables were as follows: 2.57 - 165 for Ca; 22.1 - 95.4 for P; 0.07 - 0.82 for Zn; 0.01 - 0.16 for Cu and 0.27 - 3.31 for Fe. These measurements allowed to estimate the realisation of the recommended daily intake of bioelements with the analysed vegetables for an adult person.


Assuntos
Cálcio/análise , Cobre/análise , Ferro/análise , Fósforo/análise , Verduras/química , Zinco/análise , Manipulação de Alimentos , Conservação de Alimentos , Humanos , Necessidades Nutricionais , Valor Nutritivo , Reprodutibilidade dos Testes , Espectrofotometria Atômica/métodos
6.
Rocz Panstw Zakl Hig ; 58(1): 339-43, 2007.
Artigo em Polonês | MEDLINE | ID: mdl-17711132

RESUMO

Concentrations of Ca, P, Fe, Zn, Cu and Mn were determined in nuts, almonds as well as in dry fruits available on Polish market. The contents of minerals in 100 g of nuts were as follows: 55.8-261 mg Ca; 294-724 mg P; 1.11-3.06 mg Fe; 2.05-4.98 mg Zn; 0.5-1.38 mg Cu and 0.93-5.75 mg Mn. Among the analysed dry fruits, the greatest concentrations of calcium, phosphorus, zinc and cooper were recorded for figs, while apricots contained the highest levels of iron and manganese. Based on the data obtained it was possible to estimate the realization of the recommended daily intake of essential elements with the 100 g portion of analysed products for an adult person.


Assuntos
Cálcio/análise , Frutas/química , Valor Nutritivo , Nozes/química , Fósforo/análise , Oligoelementos/análise , Cobre/análise , Manipulação de Alimentos , Conservação de Alimentos , Ferro/análise , Manganês/análise , Prunus/química , Zinco/análise
7.
Sci Total Environ ; 383(1-3): 59-69, 2007 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-17560631

RESUMO

The concentrations of 14 elements (Ca, Mg, K, Na, P, Co, Mn, Fe, Cr, Ni, Zn, Cu, Cd, Pb) were determined in market coffee samples after dry mineralisation of both dry samples and infusions evaporated to dryness. The total metal contents were analysed by flame atomic absorption spectrometry (F-AAS) using deuterium-background correction. Phosphorus was determined in the form of phosphomolybdate by spectrophotometric method. Reliability of the procedure was checked by the analysis of the certified reference materials Tea (NCS DC 73351), Cabbage (IAEA-359) and Spinach leaves (NIST-1570). It was concluded, based on RDA calculated for essential metals, that coffee infusions are not an important source of bioelements in human diet. In the case of toxic elements Provisional Tolerable Weekly Intake (PTWI) was estimated and there is no health hazard associated with exposure to Cd and Pb via coffee consumption. Significant correlation coefficients (p<0.001, p<0.01 and p<0.05) were found between concentrations of some metals in coffee. Factor analysis and canonical analysis were applied to the data processing in order to characterise the market coffee samples. The 12 metals determined were considered as chemical descriptors of each sample. Based on the mineral composition, it was possible to differentiate chemometrically particular types of coffee distinguishing arabica from robusta, ground from instant coffee, and their infusions.


Assuntos
Coffea/química , Café/química , Poluentes Ambientais/análise , Contaminação de Alimentos/análise , Metais/análise , Monitoramento Ambiental , Humanos , Medição de Risco
8.
J Chromatogr A ; 1094(1-2): 91-8, 2005 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-16257294

RESUMO

The method for the simultaneous determination of thiamine hydrochloride, pyridoxine hydrochloride and cyanocobalamin by high-performance liquid chromatography (HPLC) with coulometric electrochemical and UV detections is presented. The retention time of vitamins was repeatedly determined by isocratic elution using 0.05 M phosphate buffer-10% methanol and 0.018 M trimethylamine (1 ml min(-1), pH 3.55) as mobile phase with the Supelco LC 18 column 5 microm (25 cm x 4.6 mm). The specificity of the method was demonstrated by the retention characteristics, coulometric electrochemical and UV detection. The limits of detection of thiamine, pyridoxine and cyanocobalamin were: 9.2, 2.7 and 0.08 ng/ml, respectively. The method was characterized also by wide concentration range, high sensitivity and good accuracy (99.6-102.7%). The repeatability of the method was evaluated at different level of concentration of vitamins and the relative standard deviation was below 4.5%. The method was successfully applied for the quantification of Vitamins B1, B6 and B12 in pharmaceutical preparations and dietary supplements.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Eletroquímica/métodos , Preparações Farmacêuticas/química , Piridoxina/análise , Espectrofotometria Ultravioleta/métodos , Tiamina/análise , Vitamina B 12/análise , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
Rocz Panstw Zakl Hig ; 56(2): 171-8, 2005.
Artigo em Polonês | MEDLINE | ID: mdl-16252809

RESUMO

Concentrations of Ca, P, Fe, Zn and Cu were determined in grain products such as bread and crispbread with natural supplements, and also in seeds and other cereal products available on Polish market, added to improve bread's quality and nutritional value. The contents of minerals in bread were as follow: 35.3-78.4 mg Ca; 88.4-364 mg P; 3.03-5.63 mg Fe; 1.96-3.15 mg Zn and 0.27-0.64 mg Cu in 100 g of product. Among the analyzed products, the highest level of calcium was recorded for poppy and sesame seeds. Based on the data obtained it was possible to estimate the realization of the recommended daily intake of bioelements with the analyzed products for an adult person.


Assuntos
Pão/análise , Cálcio/análise , Cobre/análise , Ferro/análise , Fósforo/análise , Zinco/análise , Carboidratos da Dieta/análise , Farinha/análise , Alimentos Fortificados/análise , Humanos , Necessidades Nutricionais , Valor Nutritivo , Polônia , Sementes/química
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