Raquel Fernanda Milani

A comprehensive investigation of the mineral composition of brazilian bee pollen: geographic and seasonal variations and contribution to human diet

The mineral composition of bee pollen was investigated in 154 samples from different Brazilian regions. Ca, Cu, Fe, K, Mg, Mn, Na, P, Se and Zn were determined by ICP OES after microwave mineralization. Employing optimized instrumental parameters, the method was shown to have a good precision and accuracy for the simultaneous determination of minerals. Overall, samples from the Northeastern states presented significantly higher amounts of minerals and showed constant production throughout the year. Manganese, Se, Cu, Zn and Fe were the elements that showed the greatest possible contributions to the diet, contributing with 70, 37, 27, 17 and 17%, respectively, of the Brazilian recommended daily intake. Principal component analysis (PCA) was applied to study geographic effects. The elements Ca, Cu, Fe, K, Mg, Mn, Na, P and Zn were important in explaining the classification of pollen according to their geographical origin. The mineral levels varied widely during the year.

Inorganic Contaminants in Bee Pollen from Southeastern Brazil

A set of experiments was carried out to validate a method for inorganic contaminants in honeybee-collected pollen, consisting of digestion of the samples in a closed microwave-assisted system and quantification of 10 inorganic contaminants by ICP OES. Forty-three samples of Brazilian bee pollen, collected in southeastern Brazil during one year, were analyzed. Determination of these analytes is important both as bioindicators of pollution and to verify the safety of consuming the pollen itself. The method had satisfactory performance, with good accuracy and precision. The ranges of the mean levels were 10.4-268.0 mg/kg for Al, <0.01-1.38 mg/kg for As, 2.78-17.63 mg/kg for Ba, 0.003-0.233 mg/kg for Cd, <0.01-1.11 mg/kg for Co, <0.01-2.32 mg/kg for Cr, <0.10-1.13 mg/kg for Ni, <0.01-0.44 mg/kg for Pb, <0.035-1.33 mg/kg for Sb, and <0.0004-0.0068 mg/kg for Hg. Contamination seemed to occur in the following decreasing order: Sao Paulo > Minas Gerais > Espirito Santo. Generally higher levels of all studied contaminants were observed in samples produced in an urban site, compared to those of a rural site. Al, Cd, Co, and Pb tended to have higher levels during the dry months (July-October). Ingestion estimates showed that Al and As would have the highest contributions to the adult diet, reaching 27 and 8%, respectively, of the provisional tolerable weekly intake (PTWI) values, considering a daily portion of 25 g.

Iron-binding properties of sugar cane yeast peptides.

The extract of sugar-cane yeast (Saccharomyces cerevisiae) was enzymatically hydrolysed by Alcalase, Protex or Viscozyme. Hydrolysates were fractionated using a membrane ultrafiltration system and peptides smaller than 5kDa were evaluated for iron chelating ability through measurements of iron solubility, binding capacity and dialyzability. Iron-chelating peptides were isolated using immobilized metal affinity chromatography (IMAC). They showed higher content of His, Lys, and Arg than the original hydrolysates. In spite of poor iron solubility, hydrolysates of Viscozyme provided higher iron dialyzability than those of other enzymes. This means that more chelates of iron or complexes were formed and these kept the iron stable during simulated gastro-intestinal digestion in vitro, improving its dialyzability.

Evaluation of Direct Analysis for Trace Elements in Tea and Herbal Beverages by ICP-MS

In general, inductively coupled plasma mass spectrometry (ICP-MS) food analysis requires numerous sample treatment steps that imply an increase of analysis time and the use of chemicals. In this study, the main objective was to evaluate the applicability of the direct analysis by ICP-MS to determine twelve elements (Al, As, Ba, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Se and Zn) in tea and herbal beverages. Direct analysis method was compared with two other sample treatments: minimum treatment (acid dilution) and using a destructive method (microwave assisted digestion). Besides the lowest time of analysis, direct analysis provides a reliable response and agrees with the “green chemistry” principles. High sensitivity was also observed by low values of limits of detection and quantification, in general, below 2.5 µg L-1. The method accuracy was evaluated by spiked experiments and values ranged between 82 and 120%. Low values of coefficient of variation were also observed, 2 to 17%, for all analytes. The method exhibited applicability for commercial tea samples as well as for drinks made by herb infusion.

Cadmium, lead, tin, total mercury, and methylmercury in canned tuna commercialised in São Paulo, Brazil

ABSTRACT The objective of this work was to determine levels of inorganic contaminants in 30 samples of five commercial brands of canned tuna, acquired on the local market in Campinas, São Paulo, Brazil, in the year of 2015. Total mercury and methylmercury (MeHg+) were determined by atomic absorption with thermal decomposition and amalgamation; and cadmium, lead, and tin were determined by inductively coupled plasma optical emission spectrometry. Results indicated that 20% of the tuna samples surpassed limits determined by the Brazilian and European Commission legislation for cadmium; for lead, the maximum value found was 59 µg kg−1 and tin was not detected in any samples. The maximum values found for total Hg and MeHg+ were 261 and 258 µg kg−1, respectively. As from the results obtained, it was estimated that the consumption of four cans per week (540 g) of tuna canned in water could surpass the provisional tolerable monthly intake for MeHg+ by 100%.

Risk estimation to human health caused by the mercury content of Sushi and Sashimi sold in Japanese restaurants in Brazil

ABSTRACT Although fish is a healthy alternative for meat, it can be a vehicle for mercury (Hg), including in its most toxic organic form, methylmercury (MeHg). The objective of the present study was to estimate the risk to human health caused by the consumption of sushi and sashimi as commercialized by Japanese food restaurants in the city of Campinas (SP, Brazil). The total Hg content was determined by atomic absorption spectrometry with thermal decomposition and amalgamation, and the MeHg content calculated considering that 90% of the total Hg is in the organic form. The health risk was estimated from the values for the provisional tolerable weekly ingestion (PTWI) by both adults and children. The mean concentrations for total Hg were: 147.99, 6.13, and 3.42 µg kg−1 in the tuna, kani, and salmon sushi samples, respectively, and 589.09, 85.09, and 11.38 µg kg−1 in the tuna, octopus and salmon sashimi samples, respectively. The tuna samples showed the highest Hg concentrations. One portion of tuna sashimi exceeded the PTWI value for MeHg established for children and adults. The estimate of risk for human health indicated that the level of toxicity depended on the type of fish and size of the portion consumed.

Quantification of mineral composition of Brazilian bee pollen by near infrared spectroscopy and PLS regression

Bee pollen consumption has increased in the last years, mainly due to its nutritional value and therapeutic applications. The quantification of mineral constituents is of great importance in order to evaluate both, the toxicity and the beneficial effect of essential elements. The purpose of this work was to quantify the essential elements, Ca, Mg, Zn, P and K, by diffuse reflectance spectra in the near infrared region (NIR) combined with partial least squares regression (PLS), which is a clean and fast method. Reference method used was ICP OES. The determination coefficients for calibration models (R2) were above 0.87 and the mean percent calibration error varied from 5 to 10%. For external validation R2 values were higher than 0.76. The results indicated that NIR spectroscopy can be useful for an approximate quantification of these minerals in bee pollen samples and can be used as a faster alternative to the standard methodologies.

Rapid Elemental Analysis of Sugarcane Spirits by Inductively Coupled Plasma: Optical Emission Spectrometry

Abstract A simple, direct, and rapid method was developed and employed to determine arsenic, cadmium, copper, lead, and nickel in sugarcane spirits by inductively coupled plasma – optical emission spectrometry (ICP-OES). The samples were analyzed directly, avoiding the need for sample treatment or the use of toxic chemicals in agreement with the green chemistry principles. The accuracy was evaluated using spiked trials at three levels for each contaminant, with recoveries between 83 and 115%. High sensitivity was obtained, with limits of detection less than 0.008 mg L−1 for all elements but copper (0.05 mg L−1), in agreement with Brazilian and The Common Market of the South regulations. Low values of coefficient of variation were also observed, 0.4 to 7.7% for all analytes. The analysis time and sample amount required for the direct method were lower than methods that use sample treatment procedures, which is very positive for routine laboratory analysis.

Evaluation of raw soapstone (steatite) as adsorbent of trace elements present in Brazilian spirits.

The impact of soapstone (steatite) upon inorganic element contaminant concentrations in alcoholic beverages was investigated. Concentrations of As, Cd, Cu, Ni and Pb levels in 8 Brazilian spirits plus an alcoholic simulant were initially measured, and then measured following each 24h cycle of exposure to raw soapstone cups, for a total of 4 cycles/sample. The results were compared to the levels established by Brazilian and German regulations. The contact between the spirits and the soapstone reduced the Cu content by up to 50.4% and increased the Ni content by up to 622.2%, especially in the first contact cycle. The exposure of spirits to the soapstone exhibits a linear reduction in the Pb content (18.3-54.5%) while As and Cd levels remained unaltered throughout the experiments. In conclusion, crude soapstone in contact with alcoholic solutions acts as an adsorbent of trace elements (Cu and Pb) while releasing Ni.

Cadmium and lead levels consumed by patients with oral hospital diets prescriptions

INTRODUCTION The levels of cadmium (Cd) and lead (Pb) in foods should be monitored as a function of health risks. OBJECTIVE To evaluate Cd and Pb levels in oral hospital diets and in an oral food complement (OFC) according to their respective consumption by patients, and to estimate the patients exposition risk. METHODS The levels of Cd and Pb were determined by ICP-OES in samples of regular, blend, soft and renal diets and OFC, collected on 6 weekdays. About 14.3% of the diets and OFC served were analyzed. RESULTS AND DISCUSSION 163 patients participated, with mean weights and ages of 62.7 kg and 56.5 years, respectively, the majority being men (59.5%). The mean Cd content consumed was greater for men fed the regular and blend diets and similar amongst the sexes for the soft diet. The consumption of Cd (max. 21.02 μg/day) was below the provisional tolerable monthly intake (PTMI). The mean Pb ingested (max. 199.49 μg/day) was similar amongst the sexes. The soft diet showed the highest Pb content in September/2010, whereas the other showed no variation according to season. In September/2010 and January/2011, the soft and regular diets associated with the OFC offered 207.50 and 210.50 μg/day of Pb, respectively. CONCLUSIONS The combination of the diet with the OFC increased the risk of an excessive ingestion of Pb, and the vulnerability of the patients to an excessive exposition to Pb could be greater due to water and medications. It was concluded that whereas the calculated ingestion of Cd conformed to the PTMI, the Pb level and ingestion represented a risk to the health of the patients.