Antonio Sampaio Baptista

Analysis of isoflavonoids from leguminous plant extracts by RPHPLC/DAD and electrospray ionization mass spectrometry

Traditionally, food is associated with energetic and nutritious characteristics such as sources of carbohydrates, proteins and lipids. Recently, however, foods with bioactive substances such as isoflavones have received great attention. The objective of this study was therefore to evaluate the presence of the isoflavones daidzein, glycitein, genistein and their conjugated forms in grains and leaves of several leguminous plants utilized largely in Brazilian cuisine. Grains used in Peruvian cuisine were also analyzed. After extracting phenolic compounds with methanol (80%), isoflavones as detected by reversed-phase high-performance liquid chromatography/diode-array detector were only found in chickpeas and soybean. Chickpea extracts showed only the isoflavone genistein at 31 µg/g defatted flour. Detection of these isoflavones was confirmed by electrospray ionization mass and tandem mass spectrometric experiments. For soybean, a distinct distribution of isoflavones was found in hypocotyls and cotyledon. The highest concentration of isoflavones found was approximately 5.9 mg/g for hypocotyls, whereas the total concentration of isoflavone was around 0.4 mg/g for the cotyledons (dry matter). These results indicate that isoflavone concentrations vary within the different tissues of the leguminous species tested.

Residual biomass potential of commercial and pre-commercial sugarcane cultivars

Sugarcane (Saccharum spp.) is an efficient and sustainable alternative for energy generation compared to non-renewable sources. Currently, during the mechanized harvest process, the straw left in the field can be used in part for the second generation ethanol and increasing the electric energy production. Thus, this study aimed to provide information on the potential for residual biomass cultivars of sugarcane cropping system. This study provides the following information: yield of straw, depending on the calculated leaf area index and the number of tillers per linear meter; primary energy production of several sugarcane genotypes; contribution of dry tops and leaves; biomass yield; and evaluation of fiber, cellulose, hemicellulose and lignin. Preliminary results obtained by researchers of the State of Sao Paulo, Brazil, and reCviews related studies are presented. The results suggest that the production of sugarcane straw content varies according to the cultivars; the greater mass of sugarcane straw is in the top leaves and that the potential for the crude energy production of sugarcane per area unit can be increased using fiber-rich species or species that produce more straw. The straw indexes was shown to be a good indicator and allow the estimation of straw volumes generated in a sugarcane crop. The cellulose, hemicellulose and lignin composition in sugarcane is distinct among varieties. Therefore, it is possible to develop distinct biomass materials for energy production and for the development of sugarcane mills using biochemical processes and thermal routes.

Formas termolisada e viva de leveduras na redução de toxicidade causada por aflatoxinas

As aflatoxinas sao metabolitos hepatotoxicos produzidos por algumas linhagens de Aspergillus flavus, A. parasiticus e, eventualmente, por A. nomius sobre grande numero de produtos agricolas. Esta pesquisa foi conduzida para avaliar a capacidade de Saccharomyces cerevisiae, nas formas termolisada e desidratada viva, em reduzir os danos causados por aflatoxinas. Para tal, foi preparada uma dieta basica e desta se obtiveram quatro formulacoes: uma como controle; as demais contaminadas com aflatoxinas na concentracao de 400 mg kg-1, sendo duas com posterior adicao de 1% de leveduras, uma na forma termolisada e outra como desidratada viva. Um bioensaio com duracao de 28 dias foi efetuado com ratos Wistar. Foram realizados os estudos do peso relativo de orgaos internos e a analise do tecido hepatico dos animais. Os pesos relativos de orgaos internos de animais submetidos aos diferentes tratamentos nao diferiram estatisticamente entre si; o tecido do figado dos animais submetidos a dieta livre de aflatoxinas foi adotado como padrao de isento de toxidez; o tecido hepatico dos animais que receberam dieta controle com aflatoxinas apresentaram sinais claros de toxicidade; os animais que receberam dieta com aflatoxinas + 1% de levedura termolisada apresentaram sinais de toxicidade semelhantes ao controle com aflatoxinas; o tecido hepatico dos animais que receberam dieta com aflatoxinas + 1% de levedura viva apresentaram sinais de toxicidade menores do que os animais que receberam a dieta controle com aflatoxinas. As leveduras termolisadas nao foram capazes de suprimir os efeitos das aflatoxinas; as leveduras vivas apresentaram habilidade de reduzir os efeitos promovidos por aflatoxinas.

Changes in isoflavone profiles of soybean treated with gamma irradiation.

Soybean is an important Brazilian agricultural commodity that contains a high concentration of isoflavones. Many studies showed that isoflavones are active in the prevention of many human diseases. However, the correct processing techniques used to prepare the soy foodstuffs are important to maintain the active forms. The objective of this study was to evaluate the effect of gamma irradiation on the isoflavone contents of the defatted soybean flour when compared with soybean molasses, a derivative from the soybean food production. After extracting phenolic compounds with methanol aqueous solution (80%), isoflavones were detected by reverse-phase high-performance liquid chromatography/diode-array detector. The radiation doses of 2 and 5 kGy presented a small effect on the isoflavones content of defatted soy flour. Samples irradiated at 50 kGy showed lower isoflavone contents. The observed reduction in the concentration of isoflavones—daidzein, glycitein and genistein—induced by gamma radiation in soy molasses was not significant in defatted soy flour, thus suggesting that isoflavones in defatted soy flour were not eliminated by gamma radiation at rates up to 50 kGy.

BIOAVAILABILITYIron bioavailability of common beans (Phaseolus vulgaris L.) intrinsically labeled with 59Fe

A radiobioassay was performed in rats with or without iron depletion to evaluate the iron bioavailability of diets enriched with common beans and with multimixture, a nutritional supplement based on parts of foods that are not usually eaten. The full-body (59)Fe level was determined after 5h, the absorbed (59)Fe level was determined after 48 h, and the amount of (59)Fe retained was determined after 7 days. Iron bioavailability was assessed by the full-body radioactivity of the animals, determined using a solid scintillation detector. The iron bioavailability of common beans was higher in the iron-depleted animals (55.7%) than in the non-depleted animals (25.12%) because of the higher absorption rate in the iron-depleted animals. The multimixture did not influence dietary iron bioavailability. In addition, the iron bioavailability of common beans was similar to that observed in the standard source of iron for Wistar rats. Hence, common beans may be considered an adequate dietary iron source because of its high bioavailability.

Iron bioavailability of common beans (Phaseolus vulgaris L.) intrinsically labeled with 59Fe

A radiobioassay was performed in rats with or without iron depletion to evaluate the iron bioavailability of diets enriched with common beans and with multimixture, a nutritional supplement based on parts of foods that are not usually eaten. The full-body (59)Fe level was determined after 5h, the absorbed (59)Fe level was determined after 48 h, and the amount of (59)Fe retained was determined after 7 days. Iron bioavailability was assessed by the full-body radioactivity of the animals, determined using a solid scintillation detector. The iron bioavailability of common beans was higher in the iron-depleted animals (55.7%) than in the non-depleted animals (25.12%) because of the higher absorption rate in the iron-depleted animals. The multimixture did not influence dietary iron bioavailability. In addition, the iron bioavailability of common beans was similar to that observed in the standard source of iron for Wistar rats. Hence, common beans may be considered an adequate dietary iron source because of its high bioavailability.

Bioavailability of Iron in the Regional Basic Diet (RBD) with Dietary Supplement in Brazil

The consumption of the regional basic diet (RBD) determines a state of malnutrition found in the low-income population of Northeastern Brazil. A dietary supplement known as multimixture has been used as an alternative source of iron in food for the prevention and/or treatment of anemia and for the recovery from malnutrition. The purpose of the present work was to evaluate the bioavailability of iron in the RBD supplemented with multimixture in iron-depleted and non-depleted Wistar rats. To produce iron depletion in the animals, pretest depletion diets without iron and the pretest control diet based on the AIN-93 diet were used for 8xa0weeks. This phase was followed by the test diets: control, AIN-93 extrinsically labeled with 59FeCl3; RBD, containing carioca beans intrinsically labeled with 59Fe; and RBDMM, RBD plus multimixture, supplied in a single meal. Hemoglobin concentration, weight gain, and dietary intake were determined in the pretest phase. Iron bioavailability was determined by the determination of total-body radiation in the animals for 7xa0days, using a solid scintillation detector. The hemoglobin concentration, weight gain, and dietary intake were greater in the non-depleted animals than in the iron-depleted ones. The iron bioavailability of the diets did not differ significantly. It was concluded that the multimixture did not affect the bioavailability of Fe contained in the beans of the RBD.

Cells of yeasts adhered in corn grains and the storage perspective for use as probiotic

O comportamento da viabilidade celular de leveduras e essencial quando se almeja utiliza-la como um probiotico e o veiculo que assegure esta propriedade ate o momento do consumo e particularmente. Sobre graos de milho, contendo 16 ou 20% de umidade, foram aplicadas leveduras desidratadas vivas, nas concentracoes de 1 e de 2%. A viabilidade celular foi avaliada nos periodos de 0, 15, 30, 90 e 110 dias de armazenamento. A viabilidade celular nas leveduras nao diferiu estatisticamente entre os tratamentos aos 30 dias em armazenamento, com a viabilidade media de 89,10%. A viabilidade media encontrada aos 90 dias de 72,20% foi menor do que aquelas nos tres primeiros periodos de armazenamento. Apos 110 dias de armazenamento foi de 61,14%. Conclue-se que leveduras apresentam viabilidade celular ate 110 dias em armazenamento sobre milho e que estes podem ser utilizados como um veiculo para a aplicacao da levedura como um probiotico.