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1.
Biol Trace Elem Res ; 2023 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-37804447

RESUMO

The study aimed to assess the health value and safety associated with the consumption of the chosen 37 beetroot-based dietary supplements (DSs). An optimized and validated analytical procedure, using a method called microwave plasma atomic emission spectrometry (MP-AES), was developed to determine the profiles of 19 elements (Na, K, Fe, Ca, Pt, Zn, Cd, Cu, V, Co, Ni, Pb, Mo, Mg, Al, Mn, Sr, Cr, Ba) in the DSs. The products were assessed for compliance with the recommended daily doses for the chosen elements, and any deviations were identified. Results showed that powders constituted a richer source of elements than capsules and tablets. The exception was iron-enriched products, which provided the highest dose of Fe (3.75 to 25 mg/daily dose). Safety assessment was evaluated in 3 steps, including (1) the determination of levels of Al, Ba, Cd, and Pb; (2) comparison of their content with the permissible contamination limits; and (3) comparison of the weekly or monthly intake of Al and Cd with the provisional tolerable weekly (PTWI) or monthly (PTMI) intake, respectively. The content of Ba was evaluated because of the oral reference dose (RfD). Five products were significantly contaminated with Cd (4-134% of PTMI Cd), two with Al (11-12%), and three with Ba (1.085-1.331 µg/d.d.). Lead was not detected above the LOQ (0.035 mg/kg). Factor analysis was employed to differentiate between the pharmaceutical forms (capsules, tablets, and powders) and determine the origin of the powder contained in the capsules. These results highlight the importance of implementing more stringent control measures and regulatory changes in the DSs market to ensure consumer safety.

2.
Food Chem ; 425: 136460, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37290235

RESUMO

Micronutrients are one of the most important groups of nutrients that our body needs daily in trace amounts to tackle deficiencies. Selenium (Se) is a mineral that occurs naturally in foods and is an essential component of selenoproteins that support the healthy functioning of the human body. Therefore, monitoring dietary Se concentrations must be a higher priority to meet daily intakes. Fulfillment can be addressed through applying various analytical techniques, and the certified reference materials (CRMs) tool plays a crucial role in quality assurance/quality control (QA/QC). The availability of certified CRMs for total Se content with addition to their species is presented. The review emphasizes the necessity of incorporating more food matrix CRMs certifying Se species, apart from total Se content, to meet method validation requirements for food analysis laboratories. This would help CRM producers bridge the gap between available food matrix materials that are not certified for Se species.


Assuntos
Selênio , Humanos , Padrões de Referência , Laboratórios , Controle de Qualidade , Alimentos
3.
Nutrients ; 14(1)2021 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-35010980

RESUMO

There is a lack of data on the actual composition and effectiveness of beetroot-based dietary supplements. The research aimed to determine the profile of 22 elements (Na, K, Ca, Mg, P, Fe, As, Se, Zn, Cu, Ag, Co, Ni, Mo, Al, Mn, Sr, Cr, Ba, Li, Pb, Cd) in beetroot and its supplements by the microwave plasma atomic emission spectrometry (MP-AES) method. The analytical procedure was optimised and validated. The composition of both groups was compared, assessing compliance with the recommended daily doses for the chosen elements, and the health risk was estimated. Furthermore, chemometric analysis was applied. Beetroots constituted a significant source of elements, especially K, Na, Mg, Ca, P, in contrast to supplements which contained their negligible amounts except from iron-enriched products which provided notable amounts of Fe (38.3-88% of the Recommended Dietary Allowance for an adult male from 19 to 75 years old). Some products were significantly contaminated with toxic elements (As, Cd). Factor and cluster analyses were helpful in the differentiation of beetroot and its supplements in view of their type (vegetable, supplement, iron-enriched supplement), origin, type of cultivation (conventional, organic), and form (capsule, tablet) based on their mineral composition. The obtained results indicate the need for more stringent control of supplements, as they may pose a significant health risk to consumers.


Assuntos
Beta vulgaris/química , Quimiometria/métodos , Suplementos Nutricionais/análise , Minerais/química , Raízes de Plantas/química , Suplementos Nutricionais/toxicidade , Humanos , Fatores de Risco
4.
Anal Bioanal Chem ; 409(17): 4267-4278, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28484809

RESUMO

A novel method for indirect determination of MCPD esters levels in lipid samples has been developed. The method is based on combination of extraction and derivatization in the same sample preparation step. It is achieved by the application of diethyl ether as extraction solvent for isolation of analytes released from esterified forms from the water phase and as dilution solvent for solid PBA - the derivatization agent. It is a noteworthy improvement of recommended indirect approaches available in the literature because such steps as sample clean-up, multiple liquid-liquid extractions, and preconcentration are excluded in the proposed solution. In this way, the developed procedure is shortened and simplified. Such an approach also minimizes the utilization of organic solvents; therefore, it is in accordance with the principles of "green analytical chemistry." In spite of the fact that the step of sample clean-up is omitted, no deterioration in GC-MS system performance was observed. Equivalence testing of the developed procedure and AOCS cd 29b-13 official method (SGS) has been conducted. It was concluded that results obtained by both methods do not significantly differ statistically. The procedure has been applied to determination of MCPD esters concentrations in lipid fractions isolated by accelerated solvent extraction technique from such foodstuffs as bakery products, salty deep-fried snacks, and instant products. In all investigated samples, the level of bound MCPD was elevated. Additionally, for both procedures, the environmental impact (with the use of analytical Eco-scale) and uncertainty budget have been assessed and compared.


Assuntos
Gorduras Insaturadas na Dieta/análise , Ácidos Graxos/análise , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Química Verde/métodos , alfa-Cloridrina/análise , Esterificação , Análise de Alimentos/economia , Cromatografia Gasosa-Espectrometria de Massas/economia , Química Verde/economia , Limite de Detecção , Fatores de Tempo
5.
Crit Rev Food Sci Nutr ; 56(1): 36-55, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-24987868

RESUMO

Selenium, a "dual-surface" element, maintains a very thin line between a level of necessity and harmfulness. Because of this, a deficiency or excess of this element in an organism is dangerous and causes health-related problems, both physically and mentally. The main source of selenium is a balanced diet, with a proper selection of meat and plant products. Meanwhile, the proper assimilation of selenium into these products depends on their bioavailability, bioaccessibility, and/or bioactivity of a given selenium compound. From the time when it was discovered that selenium and its compounds have a significant influence on metabolic processes and in many countries throughout the world, a low quantity of selenium was found in different parts of the environment, pressure was put upon an effective and fast method of supplementing the environment with the help of selenium. This work describes supplementation methods applied with the use of selenium, as well as new ideas for increasing the level of this element in various organisms. Based on the fact that selenium appears in the environment at trace levels, the determination of total amount of selenium or selenium speciation in a given sample demands the selection of appropriate measurement methods. These methods are most often comprised of a sample preparation technique and/or a separation technique as well as a detection system. The work presents information on the subject of analytical methods used for determining selenium and its compounds as well as examples in literature of their application.


Assuntos
Ração Animal , Suplementos Nutricionais , Compostos de Selênio/uso terapêutico , Selênio/uso terapêutico , Ração Animal/efeitos adversos , Ração Animal/análise , Animais , Deficiências Nutricionais/dietoterapia , Deficiências Nutricionais/prevenção & controle , Deficiências Nutricionais/veterinária , Suplementos Nutricionais/efeitos adversos , Análise de Alimentos/métodos , Humanos , Valor Nutritivo , Selênio/análise , Selênio/deficiência , Selênio/intoxicação , Compostos de Selênio/efeitos adversos , Compostos de Selênio/análise , Compostos de Selênio/metabolismo
6.
Int J Food Sci Nutr ; 65(6): 692-702, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24827602

RESUMO

The correlation among selenium uptake, the content of bioactive compounds in sprouts, and biological activities triggered in cultured human cells by sprout extracts was investigated. Seeds of Brassica crops and rye were treated with SeO2 water solution. The selenium levels in sprouts increased from 1.0-4.1 to 53.3-382 µg/g dw with no influence on plant physiology according to the indices used. Neither the composition of glucosinolates (GL) in Brassica sprouts nor the myrosinase activity nor the composition of GL breakdown lipophilic products were significantly affected. In all Brassica sprouts, conversion to health-promoting isothiocyanates (ITC) and indoles corresponded to only 1% of total GLs. Low ITC concentration may explain observed lack of induction of glutathione S-transferases (GST) and quinone oxidoreductase (NQO) detoxifying enzymes in HT29 cells exposed to sprout extracts. The insignificant impact on cell growth and genome function suggests that Brassica sprouts may be safe vehicle of selenium to combat its dietary deficiency.


Assuntos
Brassica/metabolismo , Dieta , Germinação , Glucosinolatos/metabolismo , Isotiocianatos/metabolismo , Plântula/metabolismo , Selênio/metabolismo , Anticarcinógenos/farmacologia , Antioxidantes/metabolismo , Técnicas de Cultura de Células , Glutationa Transferase/metabolismo , Glicosídeo Hidrolases/metabolismo , Células HT29 , Humanos , Indóis/metabolismo , Indóis/farmacologia , NAD(P)H Desidrogenase (Quinona)/metabolismo , Extratos Vegetais/farmacologia , Selênio/deficiência , Óxidos de Selênio/metabolismo
7.
Artigo em Inglês | MEDLINE | ID: mdl-22970720

RESUMO

Selenium occurs in the environment in inorganic and organic compounds. For many years it was regarded as a toxic element, causing numerous illnesses and diseases. But research in the past 50 years has revealed a "bright side" to this element, especially as a component of selenoproteins, selenium makes a significant contribution to the health of humans and animals. The selenium content in an organism depends on its concentration and bioavailability in the soil, and the differences between its deficiency, appropriate intake, and excess are very slight. This article gathers information from the literature on: • the consequences of a deficiency and an excess of selenium in the body, as well as the health-promoting mechanisms of selenium, including the functions of selenoproteins • the uptake and transformation of selenium compounds by plants, because of the fact that selenium is better assimilated from plant food and also the classification of plants with respect to their ability to take up selenium from the soil and to accumulate it.


Assuntos
Compostos de Selênio/metabolismo , Selênio/fisiologia , Sequestradores de Radicais Livres/metabolismo , Humanos , Plantas/metabolismo , Selênio/deficiência , Selênio/toxicidade , Compostos de Selênio/química
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