Search

Worldwide, medicinal plants and herbal medicines are widely consumed. The aim of this study was to determine macro- (Ca, K, Mg, Na, and P) and microelements (Al, As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Sb, Se, Si, Sn, Sr, V, and Zn) in medicinal plants and herbal medicines: “globe artichoke” - Cynara scolymus L., “devil’s claw” - Harpagophytum procumbens D.C., and “espinheira santa” - Maytenus ilifolia (Mart) ex Reiss. Concentrations of 24 (essential and toxic potentially) elements in samples from Brazil were determined using a sequential optical emission spectrometer with inductively coupled plasma optical emission spectrometry (ICP OES) after acid digestion, assisted by microwave radiation. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were used to carry out an exploratory analysis of samples. The elements were quantified (in μg/g): Al (20.24–1261.64), Ba (18.90–63.18), Ca (2877.6–19,957.40), Cr (0.28–1.38), Cu (4.16–21.99), Fe (8.54–627.49), K (1786.12–32,297.19), Mg (505.82–6174.52), Mn (0.40–205.64), Na (1717.23–18,596.45), Ni (< LoQ–0.99), P (35.12–2899.91), Se (1.52–3.71), Sn (1.53–12.43), Sr (52.33–84.31), V (< LoQ–0.24), and Zn (2.60–30.56). As, Cd, Co, Mo, Pb, and Sb, in all the investigated samples, were found to be below the limit of detection (LoD) and quantification (LoQ) values of ICP OES. These medicinal plants and herbal medicines can be sources of Ca, K, Mg, Na, P, Cu, Fe, Mn, Se, and Zn. All samples showed considerable levels of Al. PCA and HCA showed that the samples separated into two large groups.

The objective of this study was to determine the total content and estimate the bioaccessible fraction of Cu, Fe, Mn, and Zn in chia seeds (Salvia hispanica L.) by inductively coupled plasma optical emission spectrometry (ICP OES). For the evaluation of the total content, a method of acid digestion was developed, using a complete factorial design 23, in a digester block with reflux system using cold finger, and the variables chosen were as follows: volume of nitric acid, sulfuric acid, and hydrogen peroxide. Optimization provided the best conditions considering 5.0 mL of HNO3 65% m m−1, 0.5 mL of H2SO4 98% m m−1, and 3.0 mL of H2O2 30% m m−1. The detection limits, in μg g−1, were 0.18 (Cu), 0.22 (Fe), 0.28 (Mn), and 0.37 (Zn). The analyte addition and recovery test were applied to evaluate the accuracy and recovery percentage values ranging from 84 to 114% were obtained, which is considered adequate for quantitative analysis. Precision was expressed as relative standard deviation (% RSD). It was less than or equal to 7.6% (n = 10) for all analytes. The procedure was applied to 10 samples of chia seed commercialized in Salvador (Brazil). The following concentration ranges, in μg g−1, were found: Cu (12–24.2), Fe (53.2–108), Mn (29.8–84.2), and Zn (45.8–77.4). Bioaccessibility was assessed using an in vitro method that takes into account the entire gastrointestinal tract. The following bioaccessible fractions were obtained in percent: Cu (3.6–14), Fe (5.2–5.5), Mn (5.8–29.1), and Zn (

Melipona quadrifasciata anthidioides is a species of stingless bee popularly known in Brazil as "mandacaia". Products derived from bees for food and therapeutic uses, have stimulated the evaluation of the chemical composition of geopropolis. Concentrations of 24 essential and potentially toxic elements were determined in geopropolis samples, using a sequential optical emission spectrometer with inductively coupled plasma (ICP OES) after microwave-assisted acid digestion. Principal component analysis (PCA) and Hierarchical cluster analysis (HCA) were used to carry out an exploratory analysis of the samples. The following elements were quantified (in mg Kg-1): Al (320,414.40-36,911.1), As (

Given the importance of knowing the real nutritional value of food, the main objective of this study was to evaluate the total elements concentrations and bioaccessibility of Ca, Cu, Fe, K, Mg, Mn, Mo, Na, P and Zn in linseed and sesame samples. A full 24 factorial design was applied to optimize the microwave assisted acid digestion of the samples. Total elements concentrations were obtained by inductively coupled plasma optical emission spectrometry (ICP OES). Extraction procedures were performed using the Unified Bioaccessibility Method (UBM) to evaluate the bioaccessibility. The highest total content, in μg g− 1, were observed for K (4526–9768), P (3418–7014) and Mg (2527–4633), whereas Mo (

The objective of this study was to analyze the effect of heat treatment on the bioaccessibility of major (K, Ca, Mg, P) and trace elements (As, Ba, Cu, Fe, Mn, Cd, Cr, Hg, Mo, Ni, Pb, Se, Sb, Sn, and Zn) in three different pulse species: Vigna unguiculata L. Walp (cowpea beans), Cajanus cajan L. (pigeon pea) and Lablab purpureus L. Sweet (mangalo). Analyte concentrations were determined in the samples by inductively coupled plasma mass spectrometry and inductively coupled plasma optical emission spectrometry. The results showed that thermal processing can affect the concentrations of the elements investigated in pulse samples. The influence of the heat treatment can range between legume species and chemical elements, as well as with the type of heat treatment, dry, wet, conductive heating and using microwaves.

In this paper, multivariate optimisation was applied to the development of an ultrasound-assisted multi-elemental extraction procedure to measure micronutrient minerals in coconut milk samples by inductively coupled plasma optical emission spectrometry (ICP OES). The factorial and Doehlert designs were applied to optimise the process variables. Using this approach, the optimal experimental condition for 1.0 g of coconut milk was determined: 10 min sonication time; 20.0 mL of HNO3 (1.0 mol L−1); and 5 min centrifugation time at 2000 rpm. The extraction percentage was calculated using the analyte concentration obtained by a total digestion procedure as a reference. Accuracy was assessed by analysing a certified reference material (NIST 1549). The proposed procedure was applied to the analysis of commercial samples of coconut milk, and the resulting concentration ranges, in μg g−1, were as follows: 5.8–131 (Ca)

In this work, the evaluation of the mineral profile and estimation of the bioaccessibility of essential and potentially toxic elements in honey samples was proposed. The experimental design and multivariate data analysis were applied as tool chemometrics. The acidic honey decomposition procedure using a cold finger digester block was proposed for analysis by inductively coupled plasma optical emission spectrometry (ICP OES). The analytical method presented good precision (

Biological samples can be acid-digested using open or closed reaction vessels. Each one has advantages and limitations related to sample mass, contamination, operational temperature range, and losses of analytes. The latter may be critical when working with thermolabile chemical compounds. In the present work, focused-microwave and cavity-microwave ovens were employed for acid digestion of marine invertebrate samples (oyster, mussel and clam). The aim of this study was to evaluate losses of volatile species containing As, Cd, Pb, Se, and Zn, in both microwave systems, after an acid digestion procedure using nitric and sulfuric concentrated acids. The elemental determinations were performed by inductively coupled plasma optical emission spectrometry (ICP OES) with axially viewed configuration. Using a focused-oven, losses of volatile elements were always higher than 12%, when compared to cavity-microwave oven. High losses were observed for Pb and Cd, while Zn was not affected by volatilization in marine invertebrate samples. Standard reference material (Oyster tissue, NIST SRM 1566b) was used to check the accuracy.

The present article gives an overview of recent publications and modern techniques of sample preparation for food analysis employing atomic and inorganic mass spectrometric techniques, such as flame atomic absorption spectrometry, chemical vapor generation atomic absorption and atomic fluorescence spectrometry, graphite furnace atomic absorption spectrometry, inductively coupled plasma optical emission spectrometry, and inductively coupled plasma mass spectrometry. Among the most frequently applied sample preparation techniques for food analysis are dry ashing, usually with the addition of an ashing aid, and acid digestion, preferably with the assistance of microwave energy. Slurry preparation, particularly with the assistance of ultrasound, is increasingly used to reduce acid consumption and sample preparation time. Direct analysis of solid samples is gaining importance in the field of food analysis as it offers the highest sensitivity, avoids the use of acids and other aggressive reagents, make...