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1.
An Acad Bras Cienc ; 92(3): e20181196, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33053103

RESUMO

Honey is a food of nutritional, medicinal and commercial importance. The physicochemical characteristics, pollen spectrum and mineral composition of eighteen honey samples obtained from regions (Cachoeira, Coqueiros, Maragojipe and Santiago do Iguape) near the Paraguaçu River, Bahia, Brazil were evaluated. Botanical families Asteraceae, Leguminosae, Malvaceae, Myrtaceae and Palmae were most frequently found. Five samples had water contents above the maximum limit established by the Brazilian legislation (> 20%). The mineral composition was determined by ICP OES, after microwave digestion. Ca, K, Mg and Na were measured (mg Kg-1) in the range from: 18.85 to 79.61; 366.74 to 1214.98; 12.46 to 44.59 and 11.56 to 85.39, respectively. Cu, Fe, Mn and Zn had variable concentration ranges, between 0.05 and 6.13 mg Kg-1. Al, Ba, Cd, Co, Cr, Ni, Pb, Se and V showed values below the LOD. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) demonstrated that there are no similarities of mineral composition among honey samples.


Assuntos
Mel , Oligoelementos , Brasil , Mel/análise , Pólen/química , Rios , Análise Espectral , Oligoelementos/análise
2.
Environ Geochem Health ; 42(7): 2179-2193, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31853769

RESUMO

In this work, a methodology for chemical speciation analysis of inorganic As and Sb in urban dust using slurry sampling and detection by fast sequential hydride generation atomic absorption spectrometry is proposed. Doehlert design and desirability function were used to find the optimum conditions for hydride generation (1.0 mol L-1 HCl and 0.9% m v-1 NaBH4). The accuracy of the analytical method was evaluated by analysis of reference material fly ash (BCR 176R), addition and recovery tests for inorganic As species, and comparison of independent methods for Sb determination in urban dust samples. The determination of the total concentrations of As and Sb and their inorganic species presented good accuracy, between 80 ± 1 and 101 ± 6%. Precision was expressed as the relative standard deviation and was better than 4.7% (n = 3). The limit-of-quantification values were 0.23 and 1.03 mg kg-1 for As and Sb, respectively. The methodology was applied to eight samples of dust collected in an urban area of Salvador and Jaguaquara cities, Bahia, Northeast, Brazil, with an aerodynamic size lower than 38 µm. Concentrations of pentavalent inorganic species (iAs5+ and iSb5+) in relation to trivalent species (iAs3+ and iSb3+) were found in urban dust collected in the city of Salvador, which are regarded as more toxic for both elements. The enrichment factor and geoaccumulation index (Igeo) values showed that for some samples, the concentrations of iAs and iSb presented strong enrichment and, and regarding environment, strong to moderately polluted by iAs and iSb, with an indication of anthropogenic contributions. The occurrence of these inorganic constituents in the urban area of Salvador can be related with intense industrial activities and vehicular traffic.


Assuntos
Poluentes Atmosféricos/análise , Antimônio/análise , Arsênio/análise , Poeira/análise , Monitoramento Ambiental/métodos , Poluentes Atmosféricos/química , Antimônio/química , Arsênio/química , Brasil , Cidades , Limite de Detecção , Espectrofotometria Atômica
3.
J Sci Food Agric ; 99(10): 4609-4614, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30891758

RESUMO

BACKGROUND: In the present work, a simple and rapid method was proposed for the preconcentration of cadmium using ultrasound-assisted temperature-controlled ionic liquid microextraction (TC-IL-LPME). The dispersion of the ionic liquid (1-Hmim[PF6 ]) in the aqueous phase was performed by heating it in an ultrasonic bath, followed by cooling in an ice bath. After centrifugation, the enriched phase was dissolved in 45% (w/w) nitric acid solution to reduce viscosity, and the cadmium content was measured employing electrothermal atomic absorption spectrometry (ET-AAS). The 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol reagent (Br-PADAP) was used as a complexing agent. RESULTS: Under optimized conditions, the method had a detection limit of 2.0 ng L-1 and an enrichment factor of 24. The accuracy of the method was evaluated through the analysis of the certified reference material of brown bread (BCR-191). The method was applied to the determination of cadmium in samples of bread and biscuit. The limit of detection of the solid samples was 0.10 µg kg-1 . The recovery of cadmium in the samples varied between 93% and 107%. CONCLUSION: The proposed method is presented as a simple, cheap, ecological and a sensitive alternative for the determination of cadmium in bread and biscuit samples. © 2019 Society of Chemical Industry.


Assuntos
Pão/análise , Cádmio/análise , Cádmio/isolamento & purificação , Microextração em Fase Líquida/métodos , Ultrassom/métodos , Contaminação de Alimentos/análise , Líquidos Iônicos/química , Espectrofotometria Atômica , Temperatura , Ultrassom/instrumentação
4.
Environ Monit Assess ; 189(9): 444, 2017 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-28795304

RESUMO

Liquid phase microextraction (LPME) has been widely used in extraction and preconcentration systems as an excellent alternative to conventional liquid phase extraction. In this work, a critical review is presented on liquid phase microextraction techniques used in the determination of cadmium in environmental samples. LPME techniques are classified into three main groups: single-drop liquid phase microextraction (SDME), hollow fiber liquid phase microextraction (HF-LPME), and dispersive liquid-liquid microextraction (DLLME). Methods involving these liquid phase microextraction techniques are described, addressing advantages and disadvantages, samples, figures of merit, and trends.


Assuntos
Cádmio/análise , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Microextração em Fase Líquida/métodos , Meio Ambiente
5.
Neurol Neurochir Pol ; 51(6): 507-509, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28803639

RESUMO

Aortic dissection is diagnostically challenging, especially in pain-free patients. Detection of acute ischemic stroke secondary to painless aortic dissection is a challenge for emergency physicians and neurologists. We report a previously healthy 58-years old female, admitted because of nausea, dizziness, somnolence, a left-sided hemiparesis and arterial hypotension. The electrocardiogram showed atrial fibrillation with ST-elevations and ST-depressions. Perfusion CT-imaging showed a dilatation of the aortic arch and intraluminal structures indicating an intima flap of aortic dissection. Four hours after onset of symptoms the patient died on the way to the cardiac surgery. In conclusion, apart from imaging the aortic arch by computed tomography in acute stroke patients, the electrocardiogram may be indicative for aortic dissection if it shows signs for myocardial ischemia in previously healthy patients.


Assuntos
Dissecção Aórtica/complicações , Fibrilação Atrial/etiologia , Acidente Vascular Cerebral/etiologia , Feminino , Humanos , Pessoa de Meia-Idade
6.
Biol Trace Elem Res ; 201(9): 4600-4611, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36562954

RESUMO

The consumption of fruits, vegetables, and cereals in the form of flour has been an alternative for the intake of nutrients, currently seen in a society that seeks a healthier diet. Thus, the assessment of total contents and bioaccessibility is important to better understand the actual intake of nutrients or contaminants present in foods. The objective of this study was to determine the total content and estimate the bioaccessible fraction of Cu, Fe, and Zn in nutritious flours by inductively coupled plasma optical emission spectrometry (ICP OES) after microwave acid digestion. Bioaccessibility was assessed using the in vitro method, taking into account the entire gastrointestinal tract (Unified Bioaccessibility Method (UBM)). The following concentration ranges, in µg g-1, were found: Ca (341-6275), K (2984-13,953), P (476-6110), Na (< 0.39-2995), Fe (1.4-167), Cu (< 0.01-59.6), and Zn (< 0.07-30.3). Principal component analysis (PCA) and hierarchical cluster analysis (HCA) showed a tendency towards the formation of three groups. The bioaccessible fractions for Cu, Fe, and Zn were considered low, ranging from 0.96 to 40% in the gastrointestinal phase and from 4.1 to 100% in the gastric phase.


Assuntos
Oligoelementos , Ingestão de Alimentos , Farinha/análise , Minerais , Análise Espectral , Oligoelementos/análise , Humanos
7.
ScientificWorldJournal ; 2012: 676173, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22489197

RESUMO

The environmental quality of the Jacuípe River's estuary (very important in northeastern Brazil) was assessed during 2007 and 2008. In water, concentrations (mg L⁻¹) of NO2⁻ (<0.004 to 0.016), NO3⁻ (0.01 to 0.33), soluble PO4³â» (<0.02 to 0.22), dissolved oxygen (3.9 to 9.6), total contents (mg L⁻¹) of Cd (<0.001), Cu (<0.01), Pb (<0.01), and Zn (<0.1), pH (5.60 to 8.00), and electrical conductivity (0.12 to 48.60 mS cm⁻¹) agreed with environmental standards. In sediments, clay and total organic matter (%, m/m) varied, respectively, from 8.8 to 12.0 and from 1.1 to 8.8, while infrared, thermogravimetric profile, electronic micrograph, as well as X-Ray analyses showed desirable adsorptive characteristics. However, maximum exchangeable levels (mg kg⁻¹) of Cd (1.3), Cu (44.6), Pb (35.7), and Zn (43.7) and their respective maximum pseudototal concentrations (mg kg⁻¹): 19.4, 95.1, 68.2, and 30.3 were below the recommended limits. In this sense, it was possible to demonstrate good environmental preservation even with the growing number of industries and touristic activities in the evaluated estuarine area.


Assuntos
Sedimentos Geológicos/química , Clima Tropical , Água/química , Brasil , Microscopia Eletrônica , Espectrofotometria Atômica , Termogravimetria
8.
J Family Med Prim Care ; 11(6): 3336-3338, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36119336

RESUMO

SARS-CoV-2 associated coagulopathy may manifest as hypocoagulability with a propensity for bleeding. Here we report a COVID-19 patient with fatal subdural hematoma (SDH) shortly after thrombendarteriectomy (TEA), and anticoagulation together with anti-thrombotic treatment. A 83-year-old male developed sudden-onset fever triggering a first ever tonic-clonic seizure. His previous history was positive for diabetes, hypertension, hyperlipidemia, aorto-coronary bypass grafting, percutaneous, transluminal coronary angioplasty with stent implantation, peripheral occlusive artery disease with percutaneous, transluminal angioplasty of the left popliteal artery, hypoacusis, and atrial fibrillation. He had undergone TEA 10 days prior to admission because of a non-symptomatic, right-sided 70% common carotid artery stenosis. He was on clopidogrel and edoxaban on admission. He presented with coma, non-reacting, unrounded pupils, stretch synergisms, reduced tendon reflexes, and positive pyramidal signs. Cerebral CT revealed an extensive SDH over the left hemisphere with edema and mass effect and a midline shift to the right. After acute decompression surgery had been declined, the patient expired a few hours after admission. Fatal SDH may occur under clopidogrel and edoxaban during a mild COVID-19 disease after a seizure triggered by fever. Whether hypocoagulation due to COVID-19 increased the bleeding risk and thus contributed to the fatal bleeding remains speculative, but is conceivable.

9.
J Trace Elem Med Biol ; 73: 127032, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35797925

RESUMO

BACKGROUND: The simultaneous administration of drugs with food can compromise the bioaccessibility and absorption of nutrients. The objective of this study was to evaluate the influence of the use of losartan potassium (LP), metformin hydrochloride (MH), and simvastatin (S) on the in vitro bioaccessibility of micronutrients (Cu, Fe, Mn, and Zn) in oat flour from Bahia, Brazil. METHODS: The experimental procedure consisted of the in vitro extraction of the bioaccessible fraction of Cu, Fe, Mn, and Zn in oat flour-with and without LP (50 mg), MH (500 mg), and S (20 mg)-using the unified bioaccessibility method (UBM), simulating the conditions of the gastrointestinal tract. For decomposition of the samples (oat flour and residue), a digester block with a closed system was used. To determine the total content (flour and residual fraction) and bioaccessible micronutrients, inductively coupled plasma optical emission spectrometry (ICP OES) was used. RESULTS: The bioaccessible contents (µg g-1) without the addition of drugs were: Cu 5.86 ± 0.21, Fe 32.80 ± 1.32, Mn 87.90 ± 1.90, and Zn 30.33 ± 2.05, with bioaccessibility ranging from 31.5 % for Fe to 99 % for Mn. The in vitro extraction method was validated by mass balance with recovery values from 89.78 % for Cu to 101.94 % for Mn. The range of bioaccessible contents (µg g-1) were: Cu (<4.14), Fe (32.10 ± 0.20-54.10 ± 2.03), Mn (81.40 ± 0.93-93.22 ± 0.80), and Zn (<10.80-29.11 ± 2.20). The estimation of the bioaccessibility of Cu, Mn, and Zn in oat flour were compromised in the presence of LP, MH, and S (p < 0.05). CONCLUSION: Chemical interactions can occur between drugs and micronutrients. Taken together, our results highlight that LP, MH, and S can interfere with the bioaccessibility of Cu, Fe, Mn, and Zn in oat flour in patients who use these drugs, suggesting its rational use in further investigations.


Assuntos
Losartan , Metformina , Avena , Brasil , Farinha/análise , Humanos , Losartan/análise , Micronutrientes/análise , Sinvastatina , Zinco/análise
10.
Brain Hemorrhages ; 2(4): 165-167, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34192245

RESUMO

OBJECTIVES: Though rare, neurological side effects of SARS-CoV-2 vaccinations are increasingly reported. Even if the first dosage goes uncomplicated, the second dose may be complicated by severe adverse reactions as in the following case. CASE REPORT: A 52yo male developed sudden-onset reading difficulty and aphasia 7d after the second dose of an mRNA-based SARS-CoV-2 vaccine. He had a previous history of myocardial infarction, arterial hypertension, hyperlipidemia, and nephrolithiasis. Blood pressure was slightly elevated on admission. Blood tests revealed mildly elevated D-dimer, pre-diabetes and hyperuricemia. Cerebral magnetic resonance imaging revealed an intracerebral bleeding (ICB) in the left temporal lobe. Aphasia resolved almost completely within a few days. Blood pressure values were normal throughout hospitalisation. Whether there was a causal relation between the ICB and the vaccination remains speculative but cannot be definitively excluded. CONCLUSIONS: A second dose of a SARS-CoV-2 vaccination may be followed by ICB. Though the pathophysiology of ICB remains unexplained a causal relation between ICB and the vaccination cannot be excluded. Risk factors for ICB should be carefully monitored in patients undergoing SARS-CoV-2 vaccination.

11.
Talanta ; 224: 121893, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33379101

RESUMO

In this study, a method based on direct-immersion single-drop microextraction was developed for the determination of vanadium in water. The detection system uses digital images obtained directly from the solvent drop after the sorption of V(V). The extraction solvent used was the ionic liquid 1-hexyl-3-methylimidazolium hexafluorophosphate ([C6MIM][PF6]). The images were obtained directly from the solvent drop, with the aid of a camera. The digital images were stored, and the RGB (red, green, and blue) data were obtained. The data collected by the red channel were used to construct the analytical curve since it showed higher sensitivity compared with green and blue channels. Under optimized conditions, the method presented an enrichment factor of 50 and a limit of detection of 0.6 µg L-1 for 3.5 mL sample volume. The limit of quantification and the relative standard deviation (50.0 µg L-1) obtained were 1.8 µg L-1 and 4.8%, respectively. Certified reference material (Plankton) was used to assess the accuracy of the method. The simple, fast, efficient, and low-cost procedure was successfully applied to the determination of V(V) in water samples. The proposed method is also following the principles of green chemistry since it uses minimal volumes of samples, reagents, and solvents and yields a small amount of waste.

12.
Food Chem ; 365: 130474, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34265645

RESUMO

An analytical procedure for the multielement determination in enteral nutrition formulations employing slurry sampling and inductively coupled plasma optical emission spectrometry (ICP OES) is proposed. A two-level full-factorial design was applied to assess the influence of the presence of stabilizing agents (HNO3, Triton X-100 and ethanol) on the composition of the slurry. Multiple response was established as a dependent variable. The experimental conditions for the preparation of the slurry were: 2.0 mL of sample and 8.0 mL of 10% (v/v) HNO3. The limits of detection (LOD) were 5; 9; and 10 µg L-1 for Cu, Fe, Zn, respectively. For P, and K, the LOD were 8 and 24 mg L-1, respectively. The method was applied for the analysis of three enteral nutrition formulation samples and the obtained concentrations ranges were (in mg L-1): 0.41-0.43 (Cu), 2.0-2.9 (Fe), 1.7-3.1 (Zn), 682-1409 (K), and 217-344 (P).


Assuntos
Nutrição Enteral , Limite de Detecção , Análise Espectral
13.
Food Chem ; 351: 129285, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-33640775

RESUMO

Macro- and microelement determination in chocolate bars by microwave-induced plasma optical emission spectrometry (MIP OES) was evaluated after microwave-assisted sample digestion. Optimization of the sample digestion was carried out, and the recommended conditions were obtained at a temperature of 190 °C, with a digestion time of 40 min and in a mixture constituted by 2.3 mL of nitric acid, 1.0 mL of hydrogen peroxide and 4.7 mL of water. The method was applied in the analysis of chocolate bars, and the concentration ranges of the elements determined were (in mg kg-1): Ca (653-3096); Cr (<0.6-2.8); Cu (<0.16-19.5); Fe (<1.6-227); Mg (147-2775); K (3554-8573); Mn (<0.03-25.2); Na (45.6-1095); Ni (3.2-10.2); P (1111-22594) and Zn (4.8-33.3). The association of the proposed microwave-assisted acid digestion with the MIP OES technique was adequate for multi-element determination in chocolate bars for routine analysis.


Assuntos
Chocolate/análise , Micro-Ondas , Gases em Plasma/química , Espectrofotometria/métodos , Digestão , Temperatura Alta , Peróxido de Hidrogênio/química , Limite de Detecção , Metais/análise , Ácido Nítrico/química , Água/química
14.
Food Chem ; 363: 129995, 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34144423

RESUMO

Unconventional edible plants (UEP) are potential supplementary sources of minerals and bioactive compounds. However, there is still a gap in the literature on UEP composition. In this study, the multielement/proximate composition of ten UEP from Brazil was evaluated by ICP OES. Furthermore, phenolic bioactives were quantified by HPLC-UV-DAD. The UEP showed high moisture content (84.85-95.27%) and elements (in mg Kg-1): Al (122-657), Ca (145-14,229), Cu (8.3-18.81), Fe (177-586), K (12.46-34.50%), Mg (157-1,552), Mn (16.85-84.96), Na (1,107-23,775), P (2,535-6,127), Si (189-1,695), Sr (25.56-104.63) and Zn (0.3-72.31). Nine phenolic bioactive compounds (1-2,147) and three flavonoids (1-2,042 mg Kg-1) were determined. PCA and HCA grouped samples (Java ginseng, Coriander, Spearmint and Indian borage) rich in minerals. Spearmint showed high levels of transcinamic acid, kaempferol and quercetin. This study contributes to the scientific development and use of UEP.


Assuntos
Oligoelementos , Brasil , Minerais , Análise Multivariada , Plantas Comestíveis , Oligoelementos/análise
15.
Anal Chem ; 82(5): 2155-60, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20143837

RESUMO

A procedure for sample digestion based on focused microwave-induced combustion (FMIC) is proposed. This system was developed using a commercial focused microwave oven with a lab-made quartz sample holder and a modified glass vessel. Oxygen flow was used to start and support the combustion. A botanical sample was used to evaluate the operational conditions for further Al, Ba, Ca, Fe, Mg, Mn, Sr, and Zn determination by inductively coupled plasma optical emission spectrometry. Pelletized samples were positioned on the quartz holder, and 50 microL of 6 mol L(-1) NH(4)NO(3) solution was added as igniter. Combustion was completed in less than 2 min, and the temperature was higher than 950 degrees C. The use of a reflux step, the position of sample holder inside the vessel, sample mass, ignition and combustion time, oxygen flow rate, and condenser type were evaluated. Results were compared with those obtained by focused microwave-assisted wet digestion and by high pressure microwave-assisted wet digestion. Agreement of 95-103% was obtained for certified reference materials digested by FMIC (reflux step with 10 mL of 4 mol L(-1) HNO(3)). With the proposed procedure, a complete sample decomposition (residual carbon content lower than 0.5%) was achieved with low consumption of reagents as only 10 mL of diluted nitric acid was necessary. Low relative standard deviation (lower than 3.8%) was observed and high amount of sample (up to 1500 mg) could be digested that allowed lower limits of detection.

16.
J Hazard Mater ; 162(2-3): 1041-5, 2009 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-18620809

RESUMO

A separation/preconcentration procedure using solid phase extraction has been proposed for the flame atomic absorption spectrometric determination of copper and nickel at trace level in food samples. The solid phase is Dowex Optipore SD-2 resin contained on a minicolumn, where analyte ions are sorbed as 5-methyl-4-(2-thiazolylazo) resorcinol chelates. After elution using 1 mol L(-1) nitric acid solution, the analytes are determinate employing flame atomic absorption spectrometry. The optimization step was performed using a full two-level factorial design and the variables studied were: pH, reagent concentration (RC) and amount of resin on the column (AR). Under the experimental conditions established in the optimization step, the procedure allows the determination of copper and nickel with limit of detection of 1.03 and 1.90 microg L(-1), respectively and precision of 7 and 8%, for concentrations of copper and nickel of 200 microg L(-1). The effect of matrix ions was also evaluated. The accuracy was confirmed by analyzing of the followings certified reference materials: NIST SRM 1515 Apple leaves and GBW 07603 Aquatic and Terrestrial Biological Products. The developed method was successfully applied for the determination of copper and nickel in real samples including human hair, chicken meat, black tea and canned fish.


Assuntos
Cobre/análise , Análise de Alimentos/métodos , Níquel/análise , Água/química , Concentração de Íons de Hidrogênio , Indicadores e Reagentes , Espectrofotometria Atômica
17.
Food Chem ; 284: 259-263, 2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-30744855

RESUMO

In this work, an analytical method for the determination of Cd and Pb in natural coconut water samples, industrialized coconut water samples and coconut milk using high-resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS GF AAS), after minimum treatment of the sample was developed. The analytical method was applied to 46 samples collected in Salvador, Bahia (Brazil). The ranges of concentrations obtained were: 0.42-18.72 µg L-1 Cd and <0.70-36.32 µg L-1 Pb for natural coconut water samples (n = 14); <0.06-1.49 µg L-1 Cd and 6.57-29.02 µg L-1 Pb for industrialized water coconut samples (n = 16); and <0.10-5.93 ng g-1 Cd and <0.85-22.41 ng g-1 Pb for coconut milk samples (n = 16). For all samples, Cd and Pb concentrations were below the maximum tolerated values recommended by Brazilian Health Surveillance Agency (Agência Nacional de Vigilância Sanitária, ANVISA).


Assuntos
Cádmio/análise , Cocos/química , Sucos de Frutas e Vegetais/análise , Chumbo/análise , Espectrofotometria Atômica/métodos , Brasil , Cocos/metabolismo , Grafite/química , Limite de Detecção , Reprodutibilidade dos Testes , Águas Residuárias/análise
18.
Food Chem ; 273: 130-135, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30292358

RESUMO

A method for simultaneous determination of Fe (232.036 nm) and Ni (232.195 nm) in vegetable oil samples by high-resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS GF AAS) after an acid extraction of the analytes is proposed. In the extraction step, hydrochloric, nitric and acetic acid solutions were tested. The optimization of the procedure was performed by applying Doehlert matrix, and multiple response was used for simultaneous evaluation of the performance of the extraction. The optimum conditions were: extraction time of 17 min, extraction temperature of 39 °C and sonication amplitude of 42%, employing 0.5 mol L-1 HCl as the extracting solvent. The limits of quantification were 60 and 160 ng g-1 for Fe and Ni, respectively. The method was applied to the analysis of vegetable oil samples and the results were compared with a method employing inductively coupled plasma optical emission spectrometry (ICP OES).


Assuntos
Fracionamento Químico/métodos , Análise de Alimentos/métodos , Ferro/análise , Níquel/análise , Óleos de Plantas/análise , Fracionamento Químico/instrumentação , Análise de Alimentos/instrumentação , Contaminação de Alimentos/análise , Grafite/química , Análise Multivariada , Óleos de Plantas/química , Espectrofotometria Atômica/instrumentação , Espectrofotometria Atômica/métodos , Temperatura , Ultrassom
19.
Food Chem ; 273: 15-23, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30292361

RESUMO

The elemental/centesimal composition of dried fruits and capsules containing Goji berries (Lycium barbarum L.) was evaluated by ICP OES after two digestion procedures. Furthermore, phenolic acid compounds and flavonoids were quantified by HPLC-UV-DAD. Precision, accuracy, LOD and LOQ were evaluated. The samples showed similar contents of proteins, lipids and carbohydrates. The metal contents in the samples were found at different levels (minimum-maximum, in mg kg-1), as follows: Ca (181.1-200.2); Cu (1.703-2.145); Fe (7.420-7.852); K (81.78-83.59); Mg (92.58-95.12); Mn (1.630-2.570); Na (587.9-590.7); P (3.124-3.360); Se (2.812-3.345); V (0.055-0.062) and Zn (2.325-2.610). Al, As, Ba Cd, Co, Ni, P, Pb, Sb, Sn and Sr showed values below the LOD. Accuracy was assessed by analysis of tomato leaves (NIST 1573a). Eight bioactive phenolic compounds (caffeic, chlorogenic, ellagic, ferulic, gallic, p-coumaric, syringic and vanillic acids) and two flavonoids [(+)-catequin and rutin] were determined, in levels of 55.5-83.700 and 172.3-2982.4 mg kg-1, respectively.


Assuntos
Cápsulas/análise , Lycium/química , Fenóis/análise , Oligoelementos/análise , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Análise de Alimentos/métodos , Análise de Alimentos/estatística & dados numéricos , Frutas/química , Hidroxibenzoatos/análise , Limite de Detecção , Metais/análise , Micronutrientes/análise , Espectrofotometria Ultravioleta
20.
Food Chem ; 273: 64-70, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30292376

RESUMO

Four species of bivalve molluscs (Anomalocardia brasiliana, Iphigenia brasiliana, Lucina pectinata and Trachycardium muricatum) were collected in the Todos os Santos Bay (TSB), Bahia, Brazil, in order to evaluate As, Cd, Co, Cu, Cr, Fe, Mn, Ni, Pb, Se, V and Zn levels and, consequently, the risk of bivalve mollusc consumption in humans. The samples were analyzed by inductively coupled plasma optical emission spectrometry (ICP OES) and inductively coupled plasma mass spectrometry (ICP-MS) after closed-vessel microwave digestion. The accuracy was confirmed using the certified reference materials of oyster tissue (NIST 1566b) and mussel tissue (NIST 2977), and the results were statistically equivalent to the certified values. Application of principal component analysis (PCA) and hierarchical cluster analysis (HCA) showed a tendency to form two groups between samples of Lucina pectinata and Trachycardium muricatum. All species showed As and Cr concentrations higher than the maximum tolerable limit specified in Brazilian legislation.


Assuntos
Bivalves/química , Contaminação de Alimentos/análise , Contaminação de Alimentos/estatística & dados numéricos , Frutos do Mar/análise , Oligoelementos/análise , Animais , Brasil , Análise por Conglomerados , Inocuidade dos Alimentos/métodos , Humanos , Espectrometria de Massas/métodos , Metais/análise , Micro-Ondas , Análise Multivariada , Análise de Componente Principal
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