RESUMEN
The Caco-2 cell line is derived from a human colon adenocarcinoma and is generally used in toxicity assays. The ingestion of soil or dust is a significant route of human exposure to potential harmful elements (PHE), and assays of bioaccessibility or bioavailability can be used to measure the potential hazard posed by exposure to toxic substances. The in vitro digestion (UBM method) and Caco-2 cell model were used to investigate the bioaccessibility and absorption by intestinal cells of the PHE in four matrices (two urban soils and two soils with lead (Pb)-mining tailings) along with the guidance material for bioaccessibility measurements, BGS 102. The gastrointestinal (GI) compartment was simulated, and the resulting material added to Caco-2 cells. In the GI, the average bioaccessibility was 24% for cadmium (Cd), 17% for copper (Cu), 0.2% for Pb, 44% for manganese (Mn) and 6% for zinc (Zn). The poor reproducibility was attributed to the pH (6.3) and the highly complex GI fluid that formed PHE precipitates and complexes. In 2 h, Caco-2 cells absorbed 0.2 ng mg-1 of cellular protein for Cd, 13.4 ng mg-1 for Cu, 5 ng mg-1 for Mn and 31.7 µg mg-1 for Zn. Lead absorption was lower than the limit of quantification (< 2 µg L-1). Cd was presented in the cell monolayer and could interfere in the intracellular accumulation of Cu, Mn and Zn. The use of in vitro assays allowed for an estimation of the absorption of Cd, Cu, Mn and Zn from environmental matrices to be made, and except for Mn, it had a positive correlation with bioaccessible concentration, suggesting a common association of these elements in the cellular environment.
Asunto(s)
Cadmio/farmacocinética , Cobre/farmacocinética , Contaminantes Ambientales/farmacocinética , Manganeso/farmacocinética , Zinc/farmacocinética , Disponibilidad Biológica , Brasil , Células CACO-2 , Ciudades , Digestión , Polvo , Humanos , Concentración de Iones de Hidrógeno , Minería , Reproducibilidad de los Resultados , Suelo/química , Contaminantes del Suelo/farmacocinética , Pruebas de ToxicidadRESUMEN
The aim of this research paper was to characterize coagulase-positive and coagulase-negative staphylococci from raw milk, Minas cheese, and production lines of Minas cheese processing. One hundred isolates from 3 different cheese producers were characterized using molecular approaches, such as PCR, molecular typing, and DNA sequencing. Staphylococcus aureus (88% of the isolates) was the most abundant followed by Staphylococcus epidermidis, Staphylococcus hyicus, and Staphylococcus warneri. Among the 22 enterotoxin genes tested, the most frequent was seh (62% of the isolates), followed by selx and ser. Hemolysin genes were widely distributed across isolates, and Panton-Valentine leukocidin and toxic shock syndrome toxin genes were also identified. Methicillin-resistant S. aureus were staphylococcal cassette chromosome mec III, IVa, IVd, and others nontypeable. In the phenotypic antibiotic resistance, multiresistant isolates were detected and resistance to penicillin was the most observed. Using spa typing, we identified several types and described a new one, t14969, isolated from cheese. These findings suggest that antibiotic resistance and potentially virulent strains from different sources can be found in the Brazilian dairy processing environment. Further research should be conducted with collaboration from regulatory agencies to develop programs of prevention of virulent and resistant strain dissemination in dairy products and the processing environment.
Asunto(s)
Antibacterianos/farmacología , Queso/microbiología , Farmacorresistencia Bacteriana Múltiple , Staphylococcus , Animales , Brasil , Farmacorresistencia Bacteriana Múltiple/genética , Pruebas de Sensibilidad Microbiana , Leche , Staphylococcus/clasificación , Staphylococcus/efectos de los fármacos , Staphylococcus/genéticaRESUMEN
The aim of this study was to determine the physicochemical, functional and antioxidant properties of mango (MAC), pineapple (PAC) and passion fruit (PFC) co-products in order to evaluate them as ingredients for food application. Proximate composition showed low fat content (0.95-5.64 g/100 g), and high levels of dietary fiber. In pineapple and passion fruit co-products, dietary fiber represented more than 50 % of the sample. Low pH, water activity, along with high acidity indicated that these co-products would not be easily susceptible to deterioration as food ingredients. Pineapple and passion fruit co-products had significant (p < 0.05) water holding capacity (4.96 and 4.31 g water/g sample, respectively), however oil holding capacity was low (1.59-1.85 g oil/g sample) for the three matrices studied. Regarding the phenolic content, values ranged from 3.78 to 4.67 mg gallic acid equivalent/g, with MAC showing the highest content. Through high performance liquid chromatography analysis, six compounds were identified and quantified (gallic acid, p-coumaric acid, ferulic acid, caffeic acid, epicatechin, and mangiferin) in the fruit co-products. As observed for the phenolic content, the highest antioxidant activity (p < 0.05) was found in MAC when measured by both DPPH and ABTS methods. The results indicated that the fruit co-products under evaluation could be used as functional ingredient to provide dietary fiber and natural antioxidants to food products.
Asunto(s)
Ananas/química , Antioxidantes/análisis , Fibras de la Dieta/análisis , Mangifera/química , Passiflora/química , Fenoles/análisis , Antioxidantes/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Grasas/análisis , Industria de Procesamiento de Alimentos , Frutas/química , Fenoles/aislamiento & purificaciónRESUMEN
Peanut samples were irradiated (0.0, 5.2, 7.2 or 10.0 kGy), stored for a year (room temperature) and examined every three months. Mycotoxic fungi (MF) were detected in non-irradiated blanched peanuts. A dose of 5.2 kGy was found suitable to prevent MF growth in blanched samples. No MF was detected in in-shell peanuts, with or without irradiation. The colors of the control in-shell and blanched samples were, respectively, 44.72 and 60.21 (L *); 25.20 and 20.38 (Chroma); 53.05 and 86.46 (°Hue). The water activities (Aw) were 0.673 and 0.425. The corresponding fatty acids were 13.33% and 12.14% (C16:0), 44.94% and 44.92% (C18:1, ω9) and 37.10% and 37.63% (C18:2, ω6). The total phenolics (TP) were 4.62 and 2.52 mg GAE/g, with antioxidant activities (AA) of 16.97 and 10.36 µmol TEAC/g. Storage time negatively correlated with Aw (in-shell peanuts) or L *, linoleic acid, TP and AA (in-shell and blanched peanuts) but positively correlated with Aw (blanched peanuts), and with oleic acid (in-shell and blanched peanuts). Irradiation positively correlated with antioxidant activity (blanched peanuts). No correlation was found between irradiation and AA (in-shell samples) or fatty acids and TP (in-shell and blanched peanuts). Irradiation protected against MF and retained both the polyunsaturated fatty acids and polyphenols in the samples.
Asunto(s)
Arachis/microbiología , Arachis/efectos de la radiación , Irradiación de Alimentos/métodos , Hongos/aislamiento & purificación , Hongos/efectos de la radiación , Antioxidantes/análisis , Arachis/química , Ácidos Grasos/análisis , Rayos gamma , Micotoxicosis/prevención & control , Fenoles/análisisRESUMEN
In-shell, peeled and blanched peanut samples were characterized in relation to proximate composition and fatty acid profile. No difference was found in relation to its proximate composition. The three major fatty acids were palmitic acid, oleic acid, and linoleic acid. In order to investigate irradiation and storage effects, peanut samples were submitted to doses of 0.0, 5.0, 7.5 or 10.0 kGy, stored for six months at room temperature and monitored every three months. Peanuts responded differently to irradiation, particularly with regards to tocopherol contents, primary and secondary oxidation products and oil stability index. Induction periods and tocopherol contents were negatively correlated with irradiation doses and decreased moderately during storage. α-Tocopherol was the most gamma radiation sensitive and peeled samples were the most affected. A positive correlation was found among tocopherol contents and the induction period of the oils extracted from irradiated samples. Gamma radiation and storage time increased oxidation compounds production. If gamma radiation is considered an alternative for industrial scale peanut conservation, in-shell samples are the best feedstock. For the best of our knowledge this is the first article with such results; this way it may be helpful as basis for future studies on gamma radiation of in-shell crops.
Asunto(s)
Arachis/química , Arachis/efectos de la radiación , Rayos gamma , Tocoferoles/análisis , Absorción de Radiación/efectos de la radiación , Ácidos Grasos/análisis , Oxidación-Reducción/efectos de la radiación , Aceites de Plantas/química , Factores de Tiempo , Rayos UltravioletaRESUMEN
Peanut skin, which is removed in the peanut blanching process, is rich in bioactive compounds with antioxidant properties. The aims of this study were to measure bioactive compounds in peanut skins and evaluate the effect of gamma radiation on their antioxidant activity. Peanut skin samples were treated with 0.0, 5.0, 7.5, or 10.0 kGy gamma rays. Total phenolics, condensed tannins, total flavonoids, and antioxidant activity were evaluated. Extracts obtained from the peanut skins were added to refined-bleached-deodorized (RBD) soybean oil. The oxidative stability of the oil samples was determined using the Oil Stability Index method and compared to a control and synthetic antioxidants (100 mg/kg BHT and 200 mg/kg TBHQ). Gamma radiation changed total phenolic content, total condensed tannins, total flavonoid content, and the antioxidant activity. All extracts, gamma irradiated or not, presented increasing induction period (h), measured by the Oil Stability Index method, when compared with the control. Antioxidant activity of the peanut skins was higher than BHT. The present study confirmed that gamma radiation did not affect the peanut skin extracts' antioxidative properties when added to soybean oil.
Asunto(s)
Antioxidantes/análisis , Antioxidantes/efectos de la radiación , Arachis/química , Arachis/efectos de la radiación , Flavonoides/análisis , Flavonoides/efectos de la radiación , Irradiación de Alimentos , Rayos gamma , Extractos Vegetales/química , Extractos Vegetales/efectos de la radiación , Polifenoles/análisis , Polifenoles/efectos de la radiación , Proantocianidinas/análisis , Proantocianidinas/efectos de la radiación , Semillas/química , Semillas/efectos de la radiación , Aceite de Soja/químicaRESUMEN
The seeds of the jackfruit (Artocarpus heterophyllus Lam.) are an abundant waste-stream in Brazil and a potential source of chocolate aroma. The aim of the study was to characterise the aroma compounds in flours prepared from the roasted jackfruit seeds and compare them with a typical Brazilian cocoa powder. Jackfruits seeds were either left untreated, acidified or fermented before drying and roasting. The volatiles were extracted using solid phase micro extraction or solid phase extraction and analysed by gas chromatography mass spectrometry. The most odour-active volatiles were identified by GC-Olfactometry. Most of the compounds known to be odour-active character impact compounds in cocoa products were also found in the jackfruit seed flours, however, the jackfruit seeds produced many additional pyrazines, some of which were responsible for the characteristic earthy "roasted jackfruit seed" aroma. The fermented sample had the most similar aroma profile to cocoa powder.
Asunto(s)
Artocarpus/química , Análisis de los Alimentos , Manipulación de Alimentos , Odorantes/análisis , Semillas/química , Chocolate/análisis , Harina/análisis , Olfatometría , Compuestos Orgánicos Volátiles/análisisRESUMEN
Winemaking generates large amounts of by-products, a well recognized source of phenolic compounds. However, less attention has been paid to the polysaccharide-rich fraction (PRF) and effects of fractionation techniques on its potential bioactivity. Therefore, PRFs from Syrah and Tempranillo winemaking by-products were extracted under aqueous (neutral pH conditions), acidic and alkaline conditions. PRFs were screened for their monosaccharide composition, uronic acid content, homogeneity and molecular weight. Anti-inflammatory activity of PRFs were evaluated on stimulated RAW 264.7 macrophages. PRF obtained in water and/or under acidic conditions showed heterogeneous profiles. As like as in the others, a heterogeneous and complex profile was detected in extracts procured under alkaline conditions. A high content of uronic acid was found in aqueous extracts, thus indicating the presence of pectin. Pectin and hemicellulose were present in PRFs procured under acidic conditions. Alkaline conditions rendered extracts containing a complex mixture of monosaccharides, mainly xylose. This latter PRF was the only one exhibiting anti-inflammatory potential (at 100⯵g/mL) by reducing the release of TNF-α and activation of NF-κB in LPS-activated RAW 264.7 macrophages, with no effect on cell viability. Regardless of the grape variety, PRFs obtained under alkaline conditions were the best option to obtain bioactive polysaccharides with potential application as a source of anti-inflammatory compounds. A complex mixture of polymers may be responsible for the anti-inflammatory effects. Finally, according to results procured by NMR, it is possible to suggest that bioactive fractions are composed of a chain of α-L-Araf-(1â¯ââ¯3) linked, ß-D-Xylp- (1â¯ââ¯4), α-D-Glcp-(1â¯ââ¯4) linked, α-D-GalpA-(1â¯ââ¯4), α-D-Gal-(1â¯ââ¯2) forming possible RG I and RG II and xylan chains.
Asunto(s)
Antiinflamatorios/química , Antiinflamatorios/farmacología , Fraccionamiento Químico/métodos , Polisacáridos/química , Polisacáridos/farmacología , Vino , Animales , Industria de Alimentos , Tecnología de Alimentos , Concentración de Iones de Hidrógeno , Residuos Industriales , Ratones , Células RAW 264.7RESUMEN
The present work evaluated the effect of high-power ultrasonication on the structure and properties of guava juice. The microstructure, concentration of lycopene, in vitro accessibility of lycopene and physical properties (pulp sedimentation, turbidity and colour) were evaluated. The results of this study demonstrate that the ultrasonication disrupts the guava cells, releasing their content and altering the juice properties. Although this processing decreases the total amount of lycopene in guava juice, the release of lycopene from the cells increased its in vitro accessibility. Furthermore, the size reduction of the dispersed pulp particles improved the physical stability of the juice, avoiding pulp sedimentation without significant colour changes during storage. In conclusion, it is suggested that ultrasonication is an interesting alternative to improve the physical and nutritional properties of fruit juices.
Asunto(s)
Jugos de Frutas y Vegetales/análisis , Licopeno/análisis , Psidium/química , Ultrasonido/métodos , Carotenoides , Licopeno/químicaRESUMEN
Jackfruit seeds are an under-utilized waste product in many tropical countries. In this work, we demonstrate the potential of roasted jackfruit seeds to substitute for cocoa powder in cappuccino formulations. Two different flours were produced from a hard variety jackfruit by drying or fermenting the seeds prior to roasting. Next, formulations were prepared with 50%, 75%, and 100% substitution of cocoa powder with jackfruit seed flours, totalizing seven with control formulation. The acceptance of cappuccinos by consumers (n = 126) and quantitative descriptive analysis (QDA®) were used to describe the preparations. Physicochemical properties were also evaluated. When 50% and 75% cocoa powder was replaced with dry jackfruit seed flour, there was no change in sensory acceptability or technological properties; however, it is possible to identify advantages tousing dry jackfruit seed flour, including moisture reduction and high wettability, solubility and sensory acceptation of the chocolate aroma. The principal component analysis of QDA explained90% variances; cluster analysis enabled the definition of four groups for six cappuccino preparations. In fact, dry jackfruit seed flour is an innovative cocoa powder substitute; it could be used in food preparations, consequently utilizing this tropical fruit waste by incorporating it as an ingredient in a common product of the human diet.
Asunto(s)
Artocarpus , Cacao/química , Chocolate , Harina , Semillas/química , Gusto , Adolescente , Adulto , Artocarpus/química , Conducta , Bebidas/análisis , Fenómenos Químicos , Chocolate/análisis , Conducta de Ingestión de Líquido , Femenino , Fermentación , Harina/análisis , Frutas/química , Humanos , Masculino , Odorantes , Adulto JovenRESUMEN
Wheat bran is an important source for human and animal feed. Its nutritional aspects include a high content of fibre and minerals, as well as phenolic compounds that help prevent chronic diseases. However, wheat can be susceptible to contamination by fungus, which can produce mycotoxins such as deoxynivalenol (DON) and zearalenone (ZEN), causing adverse health effects. Therefore, methods should be developed to reduce possible contamination. Ozone can be used for this purpose as it is considered safe and environmental friendly. The aim of this study was to evaluate the reduction of DON and ZEN concentrations in wheat bran using the ozonation process as well as to evaluate the effect of ozonation on the nutritional quality of bran. Considering this, wheat bran naturally contaminated with both DON and ZEN was processed using ozone at different conditions. The nutritional quality of the bran was evaluated after processing considering the following aspects: the total phenolic content and the bran antioxidant capacity (by using both DPPH and ABTS radicals). The results showed that the degradation of ZEN was higher and faster than the degradation of DON, which could be explained by their molecular structures. The total phenolic content and antioxidant capacity of the bran were not affected by the ozonation process, which is preferable from a nutritional point of view. Therefore, ozonation was demonstrated to be a possible method for reducing mycotoxins in wheat bran, although more studies are needed in order to better understand and optimise processing and product quality.
Asunto(s)
Fibras de la Dieta/análisis , Contaminación de Alimentos/análisis , Ozono/química , Tricotecenos/análisis , Zearalenona/análisis , Valor NutritivoRESUMEN
Jackfruit seeds are an underutilized waste in many tropical countries. This work demonstrates the potential of roasted jackfruit seeds to develop chocolate aroma. Twenty-seven different roasted jackfruit seed flours were produced from local jackfruit by acidifying or fermenting the seeds prior to drying and then roasting under different time/temperature combinations. The chocolate aroma of groups of four flours were ranked by a sensory panel (n = 162), and response surface methodology was used to identify optimum conditions. The results indicated a significant and positive influence of fermentation and acidification on the production of chocolate aroma. SPME/GC-MS of the flours showed that important aroma compounds such as 2,3-diethyl-5-methylpyrazine and 2-phenylethyl acetate were substantially higher in the fermented product and that the more severe roasting conditions produced 2-3 times more 2,3-diethyl-5-methylpyrazine, but less 3-methylbutanal. Moisture, aw, pH, luminosity, and color were also monitored to ensure that these properties were similar to those of cocoa powder or cocoa substitutes.
Asunto(s)
Artocarpus/química , Chocolate , Odorantes/análisis , Semillas/química , Compuestos Orgánicos Volátiles/análisis , Acetatos/análisis , Adolescente , Adulto , Femenino , Fermentación , Harina , Cromatografía de Gases y Espectrometría de Masas/métodos , Humanos , Residuos Industriales , Masculino , Persona de Mediana Edad , Alcohol Feniletílico/análogos & derivados , Alcohol Feniletílico/análisis , Administración de Residuos , Adulto JovenRESUMEN
Peanut skin (PS) and meal from dry-blanched peanuts (MDBP) were evaluated as sources of phenolic compounds. PS rendered the highest total phenolic content, antioxidant capacity towards ABTS radical cation, DPPH and hydroxyl radicals as well as reducing power. Phenolic acids were present in PS and MDBP whereas proanthocyanidins and monomeric flavonoids were found only in PS as identified by HPLC-DAD-ESI-MSn. Procyanidin-rich extracts prevented oxidation in non-irradiated and gamma-irradiated fish model system. Both extracts inhibited the growth of gram-positive (Bacillus cereus, Staphylococcus aureus, Listeria monocytogenes, Geobacillus stearothermophilus) and gram-negative bacteria (Pseudomonas aeruginosa, Pseudomonas fluorescens, Salmonella Enteritidis, Salmonella Typhimurium, Escherichia coli). Regardless of the strain, phenolic acid-rich extracts showed the lowest minimum inhibitory capacity (MIC); therefore presenting higher antibacterial effect. The MIC of phenolic acid-rich extracts (24-49µgphenolics/mL) was higher but comparable to Ampicillin (10µg/mL). Thus, phenolics in PS and MDBP may serve as antioxidants and antimicrobial compounds.
Asunto(s)
Antiinfecciosos/farmacología , Antioxidantes/farmacología , Arachis , Flavonoides/farmacología , Hidroxibenzoatos/farmacología , Animales , Fenoles , Extractos Vegetales , Staphylococcus aureusRESUMEN
This work evaluated the physicochemical and structural properties of rice starch of the cultivars IAC 202 and IRGA 417 modified by irradiation. Starch samples were irradiated by (60)Co in doses 1, 2 and 5kGy, on a rate of 0.4kGy/h. A control not irradiated was used for comparison. The granule morphology and A-type X-ray diffraction pattern were not altered by irradiation. There was an increase in amylose content, carboxyl content and acidity with irradiation. Gamma radiation did not affect the thermal properties of IAC202, but increased gelatinization temperature of IRGA417, in the higher dose (5kGy). The number of long chains of amylopectin was reduced and short chains were increased for IAC202, whereas for IRGA 417, the opposite was observed, probably due to cross-linking of starch chains. Starches had their physicochemical and structural properties modified by irradiation differently.
Asunto(s)
Oryza/química , Almidón/química , Amilopectina/química , Amilosa/química , Peso Molecular , Difracción de Rayos XRESUMEN
Phenolic compounds, which naturally occur in beans, are known to have antioxidant activity, which may be partially lost during the processing of this legume. This study evaluated the effect of thermal processing and maceration on the phenolic acid and flavonoids profile and content and on the antioxidant activity of white beans. According to the results obtained from the 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) method, there were no significant differences among treatment groups analysed. When was using 1,1-diphenyl-2-pycrylhydrazyl method (DPPH), beans cooked without maceration present the higher antioxidant activity, and raw beans the lower. The phenolic acids found in greater amounts were gallic acid and chlorogenic acid. Kaempferol was only detected in the soaked and cooked samples; catechin and kaempferol-3-rutinoside were found in the highest concentrations. Quercetin and kaempferol-3-glucoside were not affected by the cooking process, either with or without maceration. In general, the heat treatment increased the antioxidant activity.
Asunto(s)
Antioxidantes/análisis , Manipulación de Alimentos , Calor , Phaseolus/química , Catequina/análisis , Ácido Clorogénico/análisis , Ácido Gálico/análisis , Hidroxibenzoatos/análisis , Quempferoles/análisisRESUMEN
Food fortification may be carried out to improve the health status of consumers. In this study, peanut skins were added at 1.3, 1.8, and 2.5% to cookies to increase their polyphenol content. Insoluble fiber was increased by up to 52%. In addition, total phenolic content and the corresponding antioxidant capacities also increased as evidenced by increases of epicatechin and procyanidin dimers A and B. In addition, trimers and tetramers of procyanidins were identified only in peanut skin-fortified cookies. Addition of 2.5% peanut skins rendered an increase of up to 30% in the total polyphenols as evaluated by high-performance liquid chromatography-diode array detection-electrospray ionization multistage mass spectrometry (HPLC-DAD-ESI-MS(n)). Sensory evaluation results demonstrated that peanut skin-fortified cookies were well accepted, which suggests that the present formulation may lend itself for commercial exploitation.
Asunto(s)
Antioxidantes/química , Arachis/química , Aditivos Alimentarios/química , Alimentos Fortificados/análisis , Polifenoles/química , Gusto , Adolescente , Adulto , Cromatografía Líquida de Alta Presión , Fibras de la Dieta/análisis , Femenino , Humanos , Masculino , Persona de Mediana Edad , Espectrometría de Masa por Ionización de Electrospray , Adulto JovenRESUMEN
The polyphenols and phaseolin interaction in common bean varieties was studied. Raw beans of three different colours were analysed: black (BRS Supremo), brown (BRS Pontal) and white (WAF-75). Based on the phaseolin digestibility in vitro and phaseolin-polyphenol complexation obtained by SDS-PAGE on a 10% polyacrylamide gel, it was observed that the polyphenols interfere with the digestibility of beans by decreasing the hydrolysis of phaseolin, especially in the darker ones. Furthermore it was possible to verify a difference in the electrophoretic pattern of phaseolin, indicating an interaction between phaseolin and polyphenols.
Asunto(s)
Fabaceae/química , Proteínas de Plantas/química , Polifenoles/química , Digestión , Electroforesis en Gel de Poliacrilamida , Hidrólisis , Unión ProteicaRESUMEN
O objetivo do presente trabalho foi avaliar as propriedades físico-químicas e a aceitação sensorial do arroz submetido à radiação gama. As amostras de arroz comercial (IRGA 417), exceto o controle, foram submetidas às doses de radiação gama de 1, 2 e 5 kGy, na taxa de dose de 0,5 kGy/h. A irradiação promoveu redução no teor de amido e amarelecimento dos grãos. Quanto às propriedades de cocção, o arroz apresentou menor absorção de água e volume de expansão e maior perda de sólidos na água de cocção, conforme o aumento nas doses de radiação. A análise sensorial revelou boa aceitabilidade do arroz pelos julgadores, exceto para a dose de 5 kGy. A dose de 1 kGy destacou-se como a melhor para irradiação de arroz, pois não apresentou diferença do controle em nenhum parâmetro estudado.
Asunto(s)
Radiación , Oryza , Fenómenos Químicos , Técnicas Microbiológicas , Análisis de los Alimentos , Composición de Alimentos , AmidohidrolasasRESUMEN
Iron deficiency can be caused by imbalance between the available amount of the mineral and the body requirement. Thus, the study of iron bioavailability has been of growing interest from the nutritional point of view, due to its recognized role in the physiological and biochemical regulation, besides the contribution to the establishment of recommendations for intake of this element depending on the individuals? requirements and disease prevention. In the assessment of bioavailability, one should use methodologies depicting the chemical forms, allowing for a thorough ana lysis of the results and repeating the physiological conditions as much as possible. Therefore, radioisotopes are ideal tracers due to the specifi city of their identifi cation and quantification. This procedure is usually characterized by good precision, due to the greater analytical sensitivity and the ability for detection ?in vivo?. This work aims to elucidate the use of radioisotopes in various methodologies for studies of iron bioavailability in animals.
La anemia por deficiencia de hierro puede ser causada por desequilibrio en la cantidad biodisponible y su necesidad orgánica. Debidoa eso, la biodisponibilidad de hierro ha sido objeto de creciente interés desde el punto de vista nutricional por el reconocido papel en laregulación fisiológica y bioquímica, además de contribuir a la fijación de la ingestión recomendada de este elemento en función de las necesidades de los individuos y para prevenir enfermedades. En la evaluación dela biodisponibilidad deberán ser utilizadas metodologías que procuren dilucidar las formas químicas, que permitan un análisis cuidadosode los resultados y que reproduzcan lo más fielmente posible las condiciones fisiológicas. Por eso, los radioisótopos trazadores son ideales,por la especificidad con que son identificados y cuantificados. Este trabajo tuvo por objetivo dilucidar la utilización de radioisótopos en diversas metodologías para estudios de biodisponibilidad de hierro en animales.
A anemia ferropriva pode ser causada pelo desequilíbrio na quantidade biodisponível e a sua necessidade orgânica. Assim, o estudode biodisponibilidade do ferro tem sido alvo de crescente interesse do ponto de vista nutricional, pelo reconhecido papel na regulaçãofisiológica e bioquímica, além de contribuir no estabelecimento das recomendações de ingestão deste elemento em função das necessidades dos indivíduos e para prevenir doenças. Na avaliação da biodisponibilidade, deverão ser utilizadas metodologias que procurem elucidar as formas químicas, que permitam uma análise criteriosados resultados e que reproduzam o mais possível as condições fisiológicas. Assim, os radioisótopos são traçadores ideais pela especificidade com que são identificados e quantificados. Esseprocedimento é normalmente caracterizado por boa precisão, devido à maior sensibilidade analítica e à capacidade de detecção in vivo. Opresente trabalho objetiva elucidar a utilização dos radioisótopos em diversas metodologias para estudos de biodisponibilidade de ferro emanimais.
Asunto(s)
Disponibilidad Biológica , Hierro , Radioisótopos , Proteínas Reguladoras del Hierro , Micronutrientes , RadioisótoposRESUMEN
O objetivo do presente estudo foi avaliar a disponibilidade do cálcio no leite de vaca (UHT) integral e desnatado misturados com: banana cultivar Nanica;mamão cultivar Formosa; maçã cultivar Gala com e sem casca; achocolatado em pó e infusão de café. As amostras foram submetidas às análises de composição centesimal, fatores antinutricionais (traninos, ácido oxálico e ácido fítico), minerais e disponibilidade de cálcio. Adotou-se delineamento experimental inteiramente ao acaso e os resultados obtidos foram submetidos à análise estatística, empregando-se o teste de Tukey e o teste de correlação de Pearson ao nível de 5 por cento. Quanto à composição, apenas os lipídios apresentaram diferença significativa entre as amostras compostas por leite integral e as compostas por leite desnatado. Somente o ferro apresentou correlação significativa positiva para a disponibilidade de cálcio. As amostras compostas por leite integral e desnatado, ambas misturadas com banana ou mamão apresentaram os melhores resultados para a disponibilidade de cálcio. As amostras formadas por misturas de leite integral e desnatado com achocolatado em pó apresentaram resultados numéricos supeiores às demais amostras analisadas com relação ao teor de cálcio, cálcio dialisado e cálcio disponível em porção de 200 mL/ amostra, provavelmente devido à formulação doa chocolatado em pó. Levando-se em consideração os dados obtidos concluiu-se que os melhores resultados foram apresentados pelos leites integral e desnatado com achocolatado e com banana. A maçã adicionada ao leite com ou sem casca não influenciou o resultado da disponibilidade do cãlcio.