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Purslane (Portulaca oleracea) and spinach (Spinacea oleracea) are species with elevated levels of oxalic acid, an antinutrient that interferes in the bioaccessibility of minerals such as calcium and iron. Evaluating methods to determine oxalic acid content with reduced matrix interference, such as employing Flame Atomic Absorption Spectrometry (FAAS), can enhance the specificity of determinations. The different matrices of purslane (whole plant, leaves, and juice) and spinach (whole plant) were tested using three extraction methods (M1, M2, and M3). The oxalic acid content was evaluated by UV-vis spectrophotometry and FAAS (Flame Atomic Absorption Spectrometry). The absence of the precipitation step in M1 resulted in high levels of oxalic acid in the investigated matrices. The quantification of oxalic acid by FAAS for M2 (6M HCl for 1 hour at 100°C) and M3 (0.25N HCl for 15 minutes at 100°C) in the samples of purslane leaves and spinach whole plants yielded statistically similar results. However, the analysis by UV-vis spectrophotometry for M2 and M3 showed significant discrepancies in all evaluated samples, suggesting interference from colored compounds in the food matrix.•Comparison of methods of extraction•Comparison of UV-vis spectrophotometer and FAAS in the quantification of oxalic acid•Analysis of antinutrients in plant matrices.

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The buritirana is a little-explored species of the Arecaceae family. The biometric and physicochemical characteristics, nutritional and chemical composition and antioxidant and antibacterial potential of the buritirana fruit fractions were evaluated here for the first time. The fruits presented an oblong shape. The pulp represented 16.58% of the whole-fruit weight (10.07 g). The moisture, ash and soluble fiber contents were similar for the whole fraction without seed (WS) and pulp. Although the total carbohydrate content was the same for seed and peel (23.24 g·100 g-1), the seed showed higher protein and insoluble fiber contents. Except for glucose (1256.63 mg·100 g-1), the seed showed the highest concentrations of mono-, di- and oligosaccharides. Mineral content ranged from 0.43 to 800 mg·100 g-1 in all fractions. The peel fraction showed the highest content of vitamin C. The physicochemical results indicate the pulp and WS fraction have potential for the production of fruit-derived food products. Protocatechuic and quinic acids and epicatechin/catechin were found in all fractions. The assay antioxidant capacity DPPH, phenolic content and total flavonoids were higher in the pulp; TEAC and ORACHF values were lower in the seed. Volatile organic compounds were not identified, and the fractions did not show antibacterial activity.

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The study evaluated the effect of goat and cow milk processing on the bioaccessibility of calcium, magnesium and zinc using different methods following the static in vitro simulation of gastrointestinal digestion: solubility and dialysis models. Raw goat and cow milks were processed to obtain pasteurized milk, yogurt and cheese. In general, goat milk and dairy products presented higher bioaccessibility of Ca and Mg than cow milk and dairy products. The milk processing affected the minerals bioaccessibility indicating the importance of food structure, composition and minerals equilibrium on the in vitro digestion and bioaccessibility prediction. The potential absorptions of Ca and Zn were higher in cheeses when compared to the milks and yogurts, independently of the method used. The minerals bioaccessibility evaluated by the solubility method was higher than the obtained by dialysis method for all the products evaluated.

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Fruta-do-lobo (Solanum lycocarpum St. Hill) is a native fruit commonly used in Brazilian folk medicine as a hypoglycemic agent. These properties are attributed to their starch, mainly its resistant fraction. Resistant starch has shown to increases the growth of Bifidobacterium and Lactobacillus in the gut, even though not being selective for these strains. In this scenario, this study aimed to investigate the potential prebiotic activity of fruta-do-lobo starch (FLS). FLS showed around 30% of resistant starch and their prebiotic potential was evaluated with five probiotic strains L. acidophilus (LA3 and LA5), L. casei (LC01) and B. animalis (BB12) and B. lactis (BLC1) in a concentration range of 1.0-2.0% of starch. In a preliminary screening, we evaluated, during 48 h, the viability of the starch with promoting growth agent. An increase in the growth of the probiotic strains tested was observed. We also evaluated the microorganism's metabolic activity by assessing the short-chain fatty acid (SCFA) production, using the best starch growth promotion conditions (2% of FLS and strains BLC1, LA5, and LC01). As expected, MRS and lactose were preferentially metabolized by BLC1, with the highest growth rates: 0.231 and 0.224 h-1, respectively. However, for this strain, the FLS growth rate (0.222 h-1) was 65% higher than FOS (0.144 h-1). Also, for LA5 FLS promoted higher growth (0.150 h-1) than FOS (0.135 h-1). Additionally, FLS promoted acetate production. These data are promising and indicate that FLS may have prebiotic potential and more studies need to be done with pathogenic microorganisms.

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Excessive sodium (Na) consumption can lead to serious health problems such as hypertension, and cardiovascular and renal diseases. Therefore, the food industry in worldwide has been trying to reduce sodium levels in processed products. The aim of this study was to validate a method and quantify sodium in processed and packaged foods and to estimate its ingestion in the consumption. In the first step, for choose the adequate analytical procedure different samples preparations (mineralization) were evaluated as wet and dry ash mineralization, as well as CsCl concentration to suppress chemical interferences for apply FAAS technique. The best performance conditions were applied for the analytical method validation: mineralization by wet digestion and adding 0.1% CsCl, which characterized the method as simple and low cost. The method was validated and was applied in 12 different processed food matrices (5 brands, 3 batches), including products of vegetable and animal origins, different majority components and interferences for Na evaluation. The results showed that sausage, hamburger, ham, bread, tomato sauce, ketchup, mustard, mayonnaise and mashed potato were classified as high-sodium foods, with mean values above 460 mg 100 g-1. It was verified that 68% of the samples were regarded as having high sodium content and the maximum value found was 2851 mg 100 g-1 for a sample of mashed potatoes. In addition, it was found that 38% of the samples presented differences in Na concentration when compared to content declared on the label. It is also observed that is possible different sodium ingestion according the combinations of processed and packaged foods in the same meal and, in this case, the sodium consumption is above than the daily value as recommended by the regulatory agencies. It was concluded that the majority of processed and packaged foods presented high sodium concentration even with efforts of the food industry to reduce the levels of this mineral and its remains an important public health problem.

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Jambu (Acmella oleracea (L.) R.K. Jansen) is a neglected plant native to the Amazon Biome. Although it is very consumed in the north of Brazil, little is known about its chemical and nutritional composition. Thus, this study aimed to characterize jambu and to evaluate the effects of the boiling process on its chemical composition. The proximate composition, minerals, total amino acids, fatty acids levels, and phytosterols were determined. In comparison with conventional vegetables jambu presented higher levels of protein (24.01%), ash (10.92%), total fiber (62.61%) some mineral such as Ca (2551.56 mg/100 g), Mg (734 mg/100 g) and Cu (2.09 mg/100 g), and amino acids such as asparagine (32.01 mg/g), glutamic acid (28.26 mg/g), valine (14.55 mg/g) and isoleucine (14.19 mg/g). A significant reduction was observed in carbohydrates, total dietary fibers, minerals, unsaturated fatty acids, and in some amino acid levels after the boiling process, with an increase in ash content, protein, and saturated fatty acids in the heat-treated jambu. Lipids, phytosterols, and some amino acid levels were not significantly affected by the hydrothermal process. Thus, this study has shown that raw and processed jambu may be good alternatives for conventional vegetables, even with nutrients losses during boiling.

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Ochratoxin A is the main contaminant mycotoxin of grapes produced mainly by Aspergillus niger and Aspergillus carbonarius. Besides, it is possible that the formation of modified mycotoxin occurs through the plant defense mechanism or also by fungus actions itself. The objective of this study was to evaluate the influence of grape variety and maturation stage on the formation of OTA and modified mycotoxin. The determination of OTA was performed by high-performance liquid chromatography, and a high-resolution mass spectrometry was used for the detection of modified ochratoxin. A positive correlation was observed between the following grapes physicochemical parameters: pH, total soluble solids, total glycosides in glucose, total anthocyanin, and OTA levels produced by A. niger and A. carbonarius. Therefore, the higher the concentrations of these parameters, the greater the production of mycotoxin in grapes. Among the elected targets, we identified the 14-decarboxy-ochratoxin A in Muscat Italia variety at veraison and 15 days after the beginning of veraison stages; and ethylamide-ochratoxin A as a biomarker in the Syrah variety at the ripeness stage.

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Despite the benefits to fish farmers, the use of antimicrobials in aquaculture has concerned consumers and competent authorities. The indiscriminate use of such substances promotes the emergence of resistant microorganisms, decreases the effectiveness of treatments, and causes possible toxic effects in humans. In Brazil, florfenicol is the only antimicrobial registered for use in aquaculture and is often used in tilapia in cage creation. Thus, this study aimed to develop a method for determination of florfenicol residues and its metabolite florfenicol amine in tilapia fillet by UPLC-MS/MS. Analytes were extracted with ethyl acetate, followed by liquid-liquid partition clean-up with hexane and SPE. The sorbents C18, phenyl and HLB-Oasis were evaluated by SPE. Phenyl sorbent showed the best results, and the extraction conditions were optimized in the sample matrix with fractional factorial design 24-1. The analytes were separated on a C18 chromatographic column (50×2.1mm×1.7µm) using water (A) and acetonitrile (B) as mobile phase at a flow rate of 0.3mLmin-1 with a linear gradient (in% B): 0-2.0min: 20%; 2.0-2.5min: increase to 90%; 2.5-3.5min: 90%; 3.0-3.5min: decrease to 20%; 4.0-5.0min: 20%. The analytes were monitored in a MS/MS triple quadrupole system by MRM mode with transitions at m/z 356.1>336.1 (florfenicol) and m/z 248.1>130.1 (florfenicol amine). The optimized method was validated obtaining LOQ values of 3 and 25ngg-1 for florfenicol and florfenicol amine, respectively, precision between 20 and 36%, absolute extraction efficiency between 38 and 80%, and adequate linearity. The method was applied to samples intended for human consumption, and within the 15 evaluated samples, only one showed florfenicol residue at 30ngg-1, which is below the maximum residue limit established in Brazil.

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Anti-microbials have been used to control the quality of the aquatic environment for both prophylactic and therapeutic purposes. Tetracyclines are among the main antimicrobials used in aquaculture, and present a particular difficulty for extraction, due to a complex structure and high interaction with components of the biological matrix. In this study, different techniques of extraction and clean-up of antimicrobials of the tetracycline class in tilapia filets have been optimized and compared, followed by validation of the methodology using the best procedure. Oxytetracycline, doxycycline, tetracycline and chlortetracycline were analyzed by HPLC-fluorescence under the following conditions: organic mobile phase composed of methanol:acetonitrile (1:1, v/v) and aqueous mobile phase containing sodium acetate (0.0375molL(-1)), calcium chloride (0.0175molL(-1)) and EDTA (0.0125molL(-1)) at pH 7.00. The chromatographic analysis was performed using a mobile phase gradient with a flow rate of 1mLmin(-1) and detection wavelength of 385/528nm (λexc/λem). Four extraction methods have been evaluated, namely: liquid-liquid partition; solid phase extraction (SPE) using phenyl, C18 and polymeric Oasis-HLB stationary phases; dispersive SPE (dSPE) using polymeric adsorbent XAD 16 resin; and QuEChERS. The methods have been optimized with fractional factorial experimental design and compared by the extraction efficiency. The liquid-liquid extraction and the QuEChERS methods showed low extraction efficiencies (14-30%) for the analytes. The use of dSPE showed good efficiency (40-60%), but with low precision and high consumption of time. Among the evaluated extraction techniques the use of SPE showed the best results, with emphasis on the phenyl phase (58-76%), and has been validated for analysis of residues of tetracyclines in tilapia muscle regarding selectivity, linearity, precision and limits of detection and quantification. The validated method was adequate for the investigation of the analytes at residue levels.

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El angiosarcoma de mama es un tumor maligno, poco frecuente y generalmente con pronóstico desalentador. Su baja frecuencia y dificultad diagnóstica explican el conocimiento incompleto que se tiene acerca del mismo. El tratamiento adecuado es la mastectomía simple, desconociéndose en la actualidad los beneficios de otros tratamientos adyuvantes. Se presentan 3 casos de angiosarcoma de localización mamaria, haciendo consideraciones sobre incidencia, diagnóstico, tratamiento y pronóstico

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Se presentan 21 pacientes portadoras de carcinoma medular de mama. La frecuencia observada es menor que la de la bibliografía consultada y la incidencia de metástasis axilares es también menor que la de los carcinomas de mama no pertenecientes a este tipo. A pesar de lo reducido de la serie y el escaso tiempo de seguimiento no se observó el buen pronóstico descripto por otros autores

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Sobre un total de 2.056 pacientes portadoras de cáncer de mama, fueron detectados 15 casos de enfermedad de Paget, siendo su frecuencia en relación al carcinoma del 0,74%. Las enfermas presentaron una edad promedio de 59,15 años; la incidencia mayor se presentó en la 6ª década de la vida. La consulta por lesión del pezón como única manifestación de la enfermedad se observó con la mayor frecuencia (80%); 2 casos se presentaron con tumor palpable y fueron clasificados como TLA (UICC). El diagnóstico se basó en la clínica, el estudio mamográfico y la biopsia del pezón. El tratamiento quirúrgico empleado dio como resultado sobrevidas similares, tanto con la operación de Halsted como con la de Madden. A pesar de no poder efectuar consideraciones estadísticas debido a que 6 de las enfermas sometidas a este último procedimiento no cumplieron 5 años, esta mastectomía ofrece una correcta terapéutica de la enfermedad en los estadios evaluados

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Se presentan 27 casos de cáncer bilateral de la mama detectados en el período compreendido entre los años 1967 y 1983. Se analizan sus diversas variantes y se realiza una actualización de esta patología

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RESUMO

El angiosarcoma de mama es un tumor maligno, poco frecuente y generalmente con pronóstico desalentador. Su baja frecuencia y dificultad diagnóstica explican el conocimiento incompleto que se tiene acerca del mismo. El tratamiento adecuado es la mastectomía simple, desconociéndose en la actualidad los beneficios de otros tratamientos adyuvantes. Se presentan 3 casos de angiosarcoma de localización mamaria, haciendo consideraciones sobre incidencia, diagnóstico, tratamiento y pronóstico (AU)

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Se presentan 21 pacientes portadoras de carcinoma medular de mama. La frecuencia observada es menor que la de la bibliografía consultada y la incidencia de metástasis axilares es también menor que la de los carcinomas de mama no pertenecientes a este tipo. A pesar de lo reducido de la serie y el escaso tiempo de seguimiento no se observó el buen pronóstico descripto por otros autores (AU)

Assuntos

RESUMO

Sobre un total de 2.056 pacientes portadoras de cáncer de mama, fueron detectados 15 casos de enfermedad de Paget, siendo su frecuencia en relación al carcinoma del 0,74%. Las enfermas presentaron una edad promedio de 59,15 años; la incidencia mayor se presentó en la 6¬ década de la vida. La consulta por lesión del pezón como única manifestación de la enfermedad se observó con la mayor frecuencia (80%); 2 casos se presentaron con tumor palpable y fueron clasificados como TLA (UICC). El diagnóstico se basó en la clínica, el estudio mamográfico y la biopsia del pezón. El tratamiento quirúrgico empleado dio como resultado sobrevidas similares, tanto con la operación de Halsted como con la de Madden. A pesar de no poder efectuar consideraciones estadísticas debido a que 6 de las enfermas sometidas a este último procedimiento no cumplieron 5 años, esta mastectomía ofrece una correcta terapéutica de la enfermedad en los estadios evaluados (AU)

Assuntos

RESUMO

Se presentan 27 casos de cáncer bilateral de la mama detectados en el período compreendido entre los años 1967 y 1983. Se analizan sus diversas variantes y se realiza una actualización de esta patología (AU)

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Se presenta la metodología para el diagnóstico de las microcalcificaciones mamarias definidas como sospechosas. El procedimiento se basa en su marcación con colorante, bajo control radiográfico, usando un señalador metálico "ad hoc". La pieza operatoria se procesa con apoyo radiológico. Se destaca que el grupo con 20 microcalcificaciones o más, es neoplásico en un 85%. Con esta sistemática se estudiaron 30 pacientes en el Instituto de Oncología Angel H. Roffo, detectando 9 carcinomas (30%) en estadio I, 4 de ellos de la variedad in situ

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Se presenta la metodología para el diagnóstico de las microcalcificaciones mamarias definidas como sospechosas. El procedimiento se basa en su marcación con colorante, bajo control radiográfico, usando un señalador metálico "ad hoc". La pieza operatoria se procesa con apoyo radiológico. Se destaca que el grupo con 20 microcalcificaciones o más, es neoplásico en un 85%. Con esta sistemática se estudiaron 30 pacientes en el Instituto de Oncología Angel H. Roffo, detectando 9 carcinomas (30%) en estadio I, 4 de ellos de la variedad in situ (AU)

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