Aspectos nutricionais de fitatos e taninos

Phytochemical evaluation of lipoxygenase-free soybean genotypes for human consumption

Abstract The present study aimed to screen genotypes for the presence/absence of lipoxygenases and to evaluate the phytochemical characteristics of lipoxygenase-free genotypes. Progenies derived from the cross between the cultivars IAC PL-2 (with lipoxygenases) and BRS 213 (lipoxygenase-free) generated 114 inbred lines in the F6/7 generation, evaluated by the qualitative colorimetric method, to verify the presence/absence of lipoxygenase isoenzymes L-1, L-2 and L-3. Eight triple-null (lipoxygenase-free) lines were confirmed by visible spectrophotometry. Progenitors and triple-null lines IAC 10-0003-1, IAC 10-0010-1, IAC 10-0010-2, IAC 10-0012, IAC 10-0043, IAC 10-0046, IAC 10-0107-1 and IAC 10-0115-2 were analyzed to assess their contents of protein, oil, phytic acid, tannins, total phenols and total flavonoids. Analyses showed significant differences in protein (from 38.80% to 41.89%) and oil (from 18.86% to 22.88%), consistent with the values observed in commercial soybean cultivars. The new triple-null lines, compared to the BRS 213 standard, showed lower contents of soluble condensed tannins; lower phytic acid in line IAC 10-0043 and greater amount of total phenols in line IAC 10-0115-2; whereas, the lines IAC 10-0010-1, IAC 10-0010-2, IAC 10-0043, IAC 10-0046 e IAC 10-0107-1 stood out with higher values of total flavonoids. The new lines will be potentially useful parents for genetic breeding and for a multiline strategy, aiming at greater phenotypic stability of lipoxygenase-free soybeans for human consumption.

Effect of feeding crude or treated tung meal (Aleurites fordii) in the diet of Rhamdia quelen on growth, digestive enzymes and biochemical parameters

Abstract This study evaluated the addition of tung (Aleurites fordii) meal to the feed of Rhamdia quelen, as an alternative to animal protein sources. Silver catfish juveniles were fed different diets which included crude tung meal, chemically treated tung meal and a control without tung meal. The chemical treatment was based on the sequential application of acid and alcohol solutions and reduced the phytic acid from 1.63 to 0.61% and condensed tannin content from 0.025 to 0.018%. The nutritional response of fish to these ingredients was evaluated over nine weeks, based on growth performance, digestive enzyme activity and biochemical responses. After nine weeks, the diet containing crude tung meal caused reduced growth (weight: -57.9%; total length: -21.09%; specific growth rate: -99.74%). This diet also reduced acid protease and lipase activities, decreased concentrations of glucose, cholesterol and triglycerides in plasma and decreased liver glycogen and glucose concentrations. However, after nine weeks, fish fed with treated tung meal showed higher growth (weight, total length and specific growth rate similar to control) and reduced metabolic changes, possibly due to the removal of antinutrients and toxic substances. At the 32% level of inclusion, the chemically treated tung meal can be considered an alternative protein source for silver catfish.

Effects of the extraction method and chromatographic separation solvent in the antioxidant activity of different species of "espinheira-santa"

Bioactivity of "espinheira-santa" leaves can be evaluated through solvent purification processes. Species of the same genus may contain different compounds, which may be separated by conventional chromatography using different solvents. The extraction process also influences the contents of these compounds. In order to optimize the above process research is required on variables such as solvents, temperature and extraction time. The objective of this work was to evaluate the antioxidant activity (ABTS, DPPH and FRAP) of extracts and purified fractions from leaves of Maytenus ilicifolia and M. aquafolium. Percolation at 28 °C for 7 days, and ultrasound at 50, 60 and 70 °C for 15 min were the extraction methods tested. Open column chromatography (silica gel) was used in the fractionation of extracts, and hexane, chloroform and methanol were the elution solvents used. The evaluation methods of the antioxidant activity were DPPH, FRAP and ABTS. Plant species showed no significant differences between methods for DPPH, but the fractions obtained with chromatography had significant differences, the crude ethanolic extract (CEE) and the methanolic been in general superior. "espinheira-santa" is a plant with antioxidant potential, but the extraction methods are not optimal. Still, it can be said that the separation by chromatography provided a better visualization of the nature of the components of that plant that best stood out in relation to the antioxidant activity.

Microwave irradiation to the rapid extraction of Stryphnodendron adstringens (Barbatimão) compounds by statistical planning

Stryphnodendron adstringens is a typical tree from Brazilian Savanah used in medicine as an anti-inflammatory and antiseptic agent. It is secondary metabolites has biological activities, so the development of efficient extraction methods is essential. Microwave irradiation through assisted extraction is innovative and highly efficient for bioactive compounds. The aim of this study was to optimize an extractive method for phenolics compounds, as tannins, from the stem bark of "barbatimão" by microwave irradiation using a statistical planning and to evaluate its consistency with conventional extraction. Microwave irradiation extraction, 16.36-22.12% of phenols and 15.91-18.69% of tannins, has a better yield when compared to conventional extraction, 14.99% of phenols and 16.70% of tannins. The method by microwave irradiation is consistent with the conventional one. However, extraction by microwave irradiation had a reduction in reaction time, reagent volume, samples amount and energy consumption when compared to conventional extraction.

Fortification of whole wheat flour with different iron compounds: effect on quality parameters and stability

The aim of this study was to evaluate the effects of fortification of whole wheat flour with different iron compounds, such as ferrous sulfate (FS), ferrous fumarate (FF), reduced iron (RI), ferric sodium ethylenediaminetetraacetate (NaFeEDTA), microencapsulated ferrous sulfate (FSm) and microencapsulated ferrous fumarate (FFm), on quality parameters: color, titratable acidity, peroxide value (PV) and hexanal values, during 120 days of storage. An iron content of 1.38 mg/100 g was quantified in non-fortified whole wheat flour and after fortification, the iron levels ranged from 4.80 to 6.29 mg/100 g. The fortification of whole wheat flour with different iron compounds showed changes on the quality parameters evaluated during storage with exception of the color. The whole flour acidity was affected mainly by NaFeEDTA. Compounds FS and FFm presented the highest PV in whole flour after 30 days of storage. Whole flours fortified with FS and FSm presented higher hexanal levels after 30 and 90 days of storage, respectively. Whole flours fortified with RI and NaFeEDTA presented more stability on quality parameters evaluated during storage period. Therefore, the different iron compounds, when used on whole wheat flour fortification, affect differently the quality of the product during storage.

Archaeometric investigations on naturally and thermally-aged iron-gall inks using different tannin sources

This paper investigates the behavior of paper strips containing iron-gall inks prepared with tannins from different sources, subjected to natural and thermally-induced aging. Results indicate that inks containing initial concentrations of ferrous sulphate ranging from 0.2 to 10.0 g are amenable to treatment with calcium phytate, and thata good correlation exists between the recovery of excess iron and the initial concentration. Infrared spectra showed an absorption band at 1,750 cm−1, typical of esther, solely in the samples prepared with a condensed tannin. The condensed nature of this tannin produced a different oxidation pattern, with iron removal inferior to those observed from inks produced with hydrolisable tannins. When tannic acid was used ferrous iron removals ranged from 0.050 to 1.800 g, decreasing to 0.5 g in the presence of copper; the same behavior was observed for the remaining hydrolisable tannins, with a lower recovery from the condensed tannin. The adopted natural aging procedure released a higher amount of ferrous iron compared to ASTM thermal aging. This was probably due to the marked effect of humidity, not considered in the thermal procedure. A series of archaeometric possibilities were used to help elucidate the degradation of cellulose strips impregnated with iron-gall inks.

Técnicas de pré-preparo de feijões em unidades produtoras de refeições das regiões Sul e Sudeste do Brasil

OBJETIVO: Considerando a importância da alimentação fora de casa nos hábitos contemporâneos e o papel cultural e nutricional do feijão na alimentação brasileira, este estudo objetivou investigar as técnicas de pré-preparo de feijão utilizadas nas Unidades Produtoras de Refeições das regiões Sul e Sudeste do Brasil. MÉTODOS: Foi elaborado um questionário, disponibilizado online. A amostra foi composta por nutricionistas responsáveis técnicos de Unidades Produtoras de Refeições e definida por saturação de tempo: o questionário esteve disponível na web por dezoito semanas. O questionário continha sistema de identificação por número do registro no respectivo órgão profissional fiscalizador de sua região, o que evitou duplas respostas e possibilitou a limitação por região do País. Os dados foram analisados por estatística descritiva básica e teste de Qui-quadrado. RESULTADOS: Registraram-se 445 respostas de nutricionistas responsáveis por 413.688 refeições diárias. Quarenta e nove por cento da amostra relataram realizar remolho do feijão. Não foi encontrada associação entre realização de remolho, tipo de feijão, número de refeições servidas ou localização geográfica da unidade produtora de refeições. Dentre as justificativas para realização de remolho do feijão, as questões operacionais sobressaíram-se às sensoriais, e, em 69% dessas Unidades Produtoras de Refeições, a água de remolho é descartada antes da cocção. CONCLUSÃO: Observou-se que a realização de remolho do feijão parece ser determinada pela percepção do nutricionista sobre sua importância, o que pode ser um reflexo da escassez de discussões quanto à influência das técnicas de preparo na qualidade nutricional e sensorial desse alimento.

Application of Comet assay to assess the effects of white bean meal on DNA of human lymphocytes

This study was conducted to evaluate the potential induction of genotoxic effects of white bean flour using the Comet assay. The test was conducted with human lymphocytes present in whole blood immediately after collection, by incubation with white bean flour in three concentrations (3.92, 9.52 and 18.18 mg/mL) at 37 ºC for 4 h followed by preparation of slides. Samples were considered positive (above 20% damage) when the damage observed to cellular DNA was higher than the negative control. No genotoxic potential was found at the doses tested. However, it would be premature to suggest absence of risk to human health of DNA damage since the exposure of cells to the extract was restricted to four hours rather than a whole cell cycle. Additionally, further information on toxicology should be obtained in future studies.

Identification and analysis of antinutritional factors in possible interactions between medications and food/nutrients in hospitalized patients

ABSTRACT Objective: To identify and analyze the presence of antinutritional factors in possible interactions between medications and foods/ nutrients of the diets prescribed for patients of the Hospital Regional Justino Luz, in the city of Picos (PI) in order to suggest their likely mechanisms. Methods: The sample was made up of 120 medical records of hospitalized patients. The charts were analyzed to verify the presence or absence of interactions between medications and foods/nutrients of the diets prescribed to the patients at the Hospital Regional Justino Luz, emphasizing the action of antinutritional factors in these interactions. Results: Of the 189 medications prescribed, 128 (67.7%) had a possible interaction with food, totaling up 98 possible interactions between nutrients/foods and medications. Therefore, 20 (20.4%), 12 (12.2%) and 11 (11.2%) possible interactions were identified with captopril, acetylsalicylic acid and spironolactone, respectively, representing, in this order, the greatest frequencies of possible interactions among drugs and foods. A total of nine antinutritional factors were found in seven vegetable foods prescribed to inpatients, in which five (55.6%) were capable of interacting with the medications. Phytates and tannins had the largest quantity of possible interactions with drugs, each with 4 (26.7%) in a total of 15 interactions. The medications aluminum hydroxide, digoxin, and paracetamol attained greater probability of interaction with antinutrients, with 5 (33.3%), 3 (20%) and 3 (20%) interactions, respectively. Conclusion: Due to the large quantity of antinutritional factors capable of interacting with drugs prescribed for inpatients, the involvement of a multiprofessional team is indispensable so that these possible interactions between foods, antinutritional factors and drugs might be foreseen, detected, and resolved.

[Chemical composition and efficacy of the multimixture as a dietary supplement: a literature review]

The aim of this work was to identify all papers already published on the nutritional supplement known as multimixture (MM) in journals with high level of scientific rigor and to evaluate the effectiveness of this product as a food supplement. The methodology was based on searching at Medline and Scielo databases, without limit of date, using the keyword multimixture. Thirty one articles were analyzed. Because of the small portion that is recommended for daily consumption, the MM cannot be considered an important source of energy, protein and minerals. Its high proportion of magnesium and/or calcium can impair the absorption of iron. Its use increases the fiber content of the diet, which can reduce the absorption of nutrients, which is not interesting in the case of malnourished children. Its high amount of phytate seems to be no problem because the prior treatment to which the bran is submitted reduces the chelating power of this compound. The possibility of poisoning by cyanide come from the cassava leaf is not discarded. Regarding the ability to promote the nutritional state, 12 out of 15 studies concluded its ineffectiveness. Considering risks and benefits and the available evidence in the literature, is not justified the use of MM as a strategy for prevention and control of malnutrition.

Anemia em catadores de material reciclável que utilizam carrinho de propulsão humana no município de Santos

OBJETIVO: Estimar a prevalência de anemia e analisar os fatores de risco a ela associados nos catadores de material reciclável que utilizam carrinho de propulsão humana do município de Santos - São Paulo. MÉTODO: Estudo transversal com 253 catadores foi realizado em julho de 2005. A coleta de informações foi feita por meio de questionário com informações sobre características individuais, ocupacionais e dietéticas. Foi realizada avaliação antropométrica e coletado sangue venoso para hemograma completo e sorologias de HIV, HCV, HBV e sífilis. A análise estatística foi feita por análise uni e multivariada (regressão logística), relacionando a anemia aos fatores de risco. RESULTADOS: A prevalência de anemia foi de 38,3%. As variáveis que mostraram associação independente com anemia no modelo multivariado foram: sexo (OR 4,11; IC95%: 1,56-10,87), infecção pelo HIV (OR 9,23; IC95%: 2,93-29,1), IMC (OR 0,21; IC95%: 0,07-0,64), anos de trabalho como catador (OR 4,54; IC95%: 1,29-16,0), consumo de leite (OR 0,36; IC95%: 0,16-0,81) e de proteína animal (OR 0,39; IC95%: 0,15-0,97). CONCLUSÃO: A prevalência de anemia entre catadores de material reciclável é elevada mesmo após a obrigatoriedade de adição de ferro nas farinhas de trigo e milho. Os catadores são excluídos das ações de proteção à saúde do trabalhador, previstas na legislação. Ações de saúde dirigidas a essa categoria profissional devem ser implementadas, garantindo a acessibilidade aos serviços de saúde.

Nutritional Value of Cassava for Use as a Staple Food and Recent Advances for Improvement

  Cassava is a drought-tolerant, staple food crop grown in tropical and subtropical areas where many people are afflicted with undernutrition, making it a potentially valuable food source for developing countries. Cassava roots are a good source of energy while the leaves provide protein, vitamins, and minerals. However, cassava roots and leaves are deficient in sulfur-containing amino acids (methionine and cysteine) and some nutrients are not optimally distributed within the plant. Cassava also contains antinutrients that can have either positive or adverse effects on health depending upon the amount ingested. Although some of these compounds act as antioxidants and anticarcinogens, they can interfere with nutrient absorption and utilization and may have toxic side effects. Efforts to add nutritional value to cassava (biofortification) by increasing the contents of protein, minerals, starch, and β-carotene are underway. The transfer of a 284 bp synthetic gene coding for a storage protein rich in essential amino acids and the crossbreeding of wild-type cassava varieties with Manihot dichotoma or Manihot oligantha have shown promising results regarding cassava protein content. Enhancing ADP glucose pyrophosphorylase activity in cassava roots or adding amylase to cassava gruels increases cassava energy density. Moreover, carotenoid-rich yellow and orange cassava may be a foodstuff for delivering provitamin A to vitamin A-depleted populations. Researchers are currently investigating the effects of cassava processing techniques on carotenoid stability and isomerization, as well as the vitamin A value of different varieties of cassava. Biofortified cassava could alleviate some aspects of food insecurity in developing countries if widely adopted.

Osteoporose em mulheres na pós-menopausa, cálcio dietético e outros fatores de risco

O objetivo deste trabalho foi examinar os principais fatores de risco associados ao desenvolvimento de osteoporose primária em mulheres na pós-menopausa com osteopenia. Setenta e seis pacientes entre 46 e 85 anos foram selecionadas; 56,6% apresentaram diagnóstico de osteopenia e 43,4%, de osteoporose, de acordo com o critério da Organização Mundial da Saúde. Os fatores de risco foram pesquisados por meio de registro clínico e questionário de freqüência alimentar. O odds ratio foi calculado por meio do aplicativo Statistica. Oitenta e seis por cento das mulheres com osteopenia e 84,8% das com osteoporose apresentaram baixa ingestão de cálcio através de produtos lácteos. O teste "t" para amostras independentes foi aplicado e não inferiu diferença significativa (p= 0,99) entre os dois grupos. No grupo com osteopenia, os fatores de risco assumiram a seguinte forma hierárquica: ausência de terapia de reposição hormonal (2,000), não-exposição ao sol (1,516), consumo de bebidas alcoólicas na juventude (1,346), consumo atual inadequado de cálcio (1,163), ausência de atividade física atual (1,145), história familiar de osteoporose (1,101), ausência de atividade física na juventude (1,006), tabagismo (0,851) e consumo atual de bebidas alcoólicas (0,827). Em conclusão, a ausência de terapia de reposição hormonal foi o fator de risco que indicou maior probabilidade de ocorrência de osteoporose entre as mulheres com osteopenia.

Adições crescentes de ácido fítico à dieta não interferiram na digestibilidade da caseína e no ganho de peso em ratos

O crescente consumo de alimentos de origem vegetal, sejam como fontes protéicas com baixo teor de gordura ou como fontes de fibras, tem acrescido à dieta humana o ácido fítico. Devido à sua carga altamente negativa, o ácido fítico tem sido visto como componente de ação antinutricional capaz de quelar minerais bivalentes, proteínas e amido, podendo comprometer a biodisponibilidade destes nutrientes. No presente estudo investigou-se a influência da adição de ácido fítico à dieta de caseína, em concentrações iguais ou até oito vezes superiores àquelas encontradas no feijão-comum Phaseolus vulgaris, cultivar IAC-Carioca (14,7mg de ácido fítico/g feijão cru), durante período experimental de dez dias, sobre os índices nutricionais Ganho de Peso, Quociente de Eficiência da Dieta, Quociente de Eficiência Protéica Líquida, Digestibilidade Aparente e Digestibilidade Verdadeira. Trinta e seis ratos machos SPF da linhagem Wistar, recém-desmamados, divididos em grupos experimentais com seis ratos cada, foram alimentados com dieta purificada AIN-93G isenta de ácido fítico (Controle) e dietas teste AIN-93G acrescidas de 218, 436, 872 e 1744mg de ácido fítico/kg de dieta (Tratamentos). Os ganhos de peso (g) e os índices de qualidade dietética e protéica não apresentaram diferença estatística (p>0,05), e os valores médios entre os grupos foram: Ganho de Peso: 59,5 ± 5,0g; Quociente de Eficiência da Dieta: 0,39 ± 0,01; Quociente de Eficiência Protéica Líquida: 3,64 ± 0,12; Digestibilidade Aparente: 92,7 ± 1,1% e Digestibilidade Verdadeira: 94,4 ± 0,9%. Os resultados demonstraram que nas condições experimentais utilizadas, o ácido fítico não foi capaz de alterar o valor nutritivo da caseína.