J. M. G. Mandarino

Isoflavonas em produtos comerciais de soja

Isoflavones, associated with soy protein consumption, constitute a group of substances involved in anti-carcinogenic activity, reduction of the loss of bone mass and decrease of blood cholesterol, are considered functional compounds. Isoflavones in commercial soy foods produced in Brazil were determined. Five soy flours (SF), four textured vegetable proteins (TVP), two hydro soluble extracts (HE) and four formulated infant foods (IF) were analyzed. Isoflavone extraction was with ethanol and acetic acid and quantification and identification were accomplished by HPLC. Soy flour and textured vegetable protein contained mostly conjugated malonyl-glucosides, a SF (96mg of aglycons equivalent/100g) and TVP (70mg of aglycons equivalent /100g), obtained from the same cultivar were different in concentration and distribution of the compounds due to processing conditions. Hydro soluble extracts and formulated infant foods had aglucones varying from 8% to 28% of the total isoflavones, but the predominant isomers were b-glucosides. Twenty-five grams of soy protein a day, from SF or TVP, contribute with more than the recommended consumption of 50mg of total isoflavones a day. In the formulated infant food the concentration of total isoflavones was lower than in the other products due to addition of other ingredients.

Environmental and genetic variation of isoflavone content of soybean seeds grown in Brazil

Abstract – The objective of this work was to evaluate isoflavoneconcentrations in seeds of different Brazilian soybean cultivars grown in a range of locations and environmental conditions in Brazil. Seeds of 233 cultivars grown in Ponta Grossa, PR, Brazil, during the 2001/2002 soybean season, and of 22 cultivars sown in different locations of Brazilian Northeast, Southeast on South regions were analyzed for total isoflavones,including daidzin, glycitin, ‑1genistin and acetylgenistin. The total isoflavonesranged from 12 mg 100 g (cv. Embrapa 48) to 461 mg 100 g ‑1 (cv. CS 305) among the 233 cultivars grown in Ponta Grossa, and the differences among them are due to genetic effects since all cultivars were grown and collected at the same locatation and year. This is an indication of the possibility of breeding for isoflavonecontent. Differences in isoflavonecontent observed in the cultivars grown in different locations permit the selection of locations for optimum isoflavone content (low or high), depending on the uses of soybean. In the Northeast region (5–8°S), higher concentrations of ‑1total isoflavoneswere observed at Sao Raimundo das Mangabeiras (232 mg 100 g ) and Tasso Fragoso (284 mg 100 g

The effect of thermal treatment of whole soybean flour on the conversion of isoflavones and inactivation of trypsin inhibitors

The aim of this paper was to evaluate the effect of the thermal treatment of whole soybean flour (WSF) on the conversion of isoflavones and the inactivation of trypsin inhibitors. Soybeans were ground and whole soybean flour was obtained and subjected to heat treatment in an oven for 10, 15 and 20min at 100, 150 and 200°C according to a 3(2) experimental design. The response functions were taken to be the contents of different isoflavone forms and the residual activity of trypsin inhibitors. The thermal treatment in the oven altered the content and profile of the different isoflavones forms. At 200°C for 20min, there was a higher conversion of malonylglycosides to acetylglycosides, β-glycosides and aglycones and a significant reduction in the activity of trypsin inhibitors. Mathematical models were established to estimate the process parameters in obtaining the WSF with isoflavone conversions and reductions in trypsin inhibitor activity.

Changes in the isoflavone profile and in the chemical composition of tempeh during processing and refrigeration

The objective of this work was to analyze changes in the isoflavone profile, determined by high performance liquid chromatography, at different processing stages and after refrigeration of tempeh. For tempeh production, clean soybean grains from cultivars BR 36 (low isoflavone content) and IAS 5 (high) were dehulled, and the separated cotyledons were hydrated and then cooked in boiling water for 30 min. Spores of the fungus Rhizopus microsporus var. oligosporus were inoculated in the cooked and cooled cotyledons, and incubated at 32oC for 6, 12, 18, and 24 hours in perforated polypropylene bags, for fermentation. The resulting tempeh was stored at 4oC for 6, 12, 18, and 24 hours. After 24‑hour fermentation, isoflavone glucosides were 50% reduced, and the aglycone forms in the tempeh from both cultivars was increased. The malonyl forms reduced 83% after cooking. Less than 24 hours of refrigeration did not affect the isoflavone profile of tempeh from either cultivar, which is a good indicator of its quality. The tempeh maintains the high and low isoflavone content of the cultivars, which indicates that cultivar differences in this trait should be considered when processing tempeh.

Snack bars with high soy protein and isoflavone content for use in diets to control dyslipidaemia

The objective was to develop a cereal bar product rich in isoflavones and soy protein to be used in diets for controlling dyslipidaemia. A soy snack bar with 39.88 g/100 g dietary fibre, 34.25 g/100 g protein, 100.39 mg/100 g isoflavones and 245.47 kcal/100 g was produced. The shelf life of the product was tested over a period of 6 months. The hardness, water activity and darkness of the snack bars increased with storage time. Clinical trial was carried out to evaluate the effectiveness of the soy snack bar on the lipid profiles of 22 dyslipidaemic subjects for a period of 45 days. There was a decrease in levels of triglycerides (TGs) ( − 20%) and an increase in high-density lipoprotein cholesterol (HDL-c) (+8%) comparing with baseline values. Therefore, relatively high intakes of soy protein and isoflavones in moderately hypercholesterolaemic subjects (>200 mg/dl) may have a moderately beneficial effect on plasma lipid profiles, as TG and HDL-c levels, without additional diet restrictions.

Evaluation of lignin content of soybean seed coat stored in a controlled environment

Breeding soybean for high seed quality is an important approach for developing cultivars for tropical regions, and the lignin content in the seed coat is one of the screening parameters for this trait. Considering that many breeding lines are evaluated in each growing season using the presently recommended method for lignin determination, a long period is required for the evaluation of the whole breeding program. This time limitation may influence lignin content assessment, if lignin is degraded during storage. This research reported was designed to determine whether lignin was degraded in the seed coat of soybean seed cultivars stored for one year in a controlled environment (10°C temperature and 50% air relative humidity). Seeds of 12 selected soybean cultivars that had a range in seed coat lignin content were evaluated. Seeds were hand harvested just after physiological maturity and evaluated for seed coat lignin content at harvest and after one year of storage in a cold room (10°C and 50% RH). The lignin content in seed coats differed significantly among cultivars in both analyses, but for both results the sequence of cultivar classification and the lignin content values of each cultivar did not change. A regression analysis of lignin content at harvest and after one year of storage indicated a direct relationship between both lignin determinations suggesting no differences between the lignin content of each cultivar due to prolonged storage (r2 = 0.98***). This indicates that the lignin determination in the soybean seed coat can be performed over a long time period without any bias due to change in its content.

Avaliações químicas e bioquímicas dos grãos, extratos e tofus de soja comum e de soja livre de Lipoxigenase

Com este trabalho, objetivou-se avaliar a composicao quimica e aspectos bioquimicos de soja comum, comum branqueada e livre de lipoxigenases e o efeito do processamento dos seus respectivos extratos de soja e tofus. A composicao centesimal das cultivares de soja comum e livre de lipoxigenase nao se diferenciaram (p>0,05). Alteracoes na composicao centesimal e de minerais dos extratos de soja e dos tofus foram atribuidas ao tratamento termico (98 oC/5 minutos) a que foi submetido o grao de soja comum e a etapa de maceracao dos graos, ficando evidente que algumas substâncias hidrossoluveis, foram migradas para a agua de maceracao dos graos; o branqueamento na soja comum no inicio do processamento reduziu o teor de alguns minerais do extrato de soja (leite de soja), bem como no tofu. Ficou evidente as perdas de isoflavonas com o processamento na obtencao do tofu, na ordem de 38% no de SC, 31% no de SCB e 56% no de SLL. O processamento termico utilizado para obtencao dos tofus foi suficiente para eliminar a atividade dos inibidores de tripsina em 79% do tofu de soja comum, 81% no tofu de soja branqueada e 82% nos tofus de soja livre de lipoxigenase.

Componentes do rendimento, teores de isoflavonas, proteínas, óleo e qualidade de sementes de soja

Soybean seeds have been used not only for animal, but also for human nutrition because of the presence of proteins; lipids; some vitamins and polyphenolic compounds, such as isoflavones, in their chemical composition. The antioxidant activity of isoflavones may be considered a safe mechanism of seed quality. This is due to the deterioration theory which leads to a cellular detriment because of the action of free radicals on cell membranes. Experiments were carried out during the 2004/05 agricultural year in two different sowing locations (Maringa and Umuarama). The objective of this study was to evaluate the yield, physiological quality of seeds produced in two sowing locations; to determine oil, protein and isoflavone contents; as well as to correlate isoflavone contents to the yield, physiological quality and oil-protein contents of soybean seeds. The seed quality was evaluated by the germination test (first count and final count); the tetrazolium test (vigor and viability) and the concentration of oil, protein and isoflavone tests. Analysis of the isoflavone contents showed that the BRS 133 and EMBRAPA 48 cultivars presented the highest isoflavone contents whereas the BR 36 cultivar showed the lowest isoflavone contents in both places. Germination was above 80% in all cultivars tested in Maringa. The correlation between isoflavones and the weight of one thousand seeds was negative for both locations.

Quantification of the sugars, oligosaccharides and starch in special soybean genotypes/cultivars (Glycine max (L) Merril) for human consumption.

Na soja, vários componentes, tais como açúcares, aminoácidos, ácidos orgânicos, sais inorgânicos, isoflavonas e saponinas estão relacionados com o sabor. Os açúcares, a sacarose e o amido, podem melhorar o sabor e a textura da soja. O objetivo deste trabalho foi quantificar os teores desses compostos e dos oligossacarídeos, em sementes de 28 genótipos/cultivares do Banco Ativo de Germoplasma da Embrapa Soja, que apresentam características especiais para o melhoramento genético. Os açúcares e os oligossacarídeos foram quantificados pela técnica de cromatografia liquida de alto desempenho (CLAE) e o amido pela metodologia adaptada de Rickard e Behn (1987). Os genótipos PI 417.159 e F83-8119 apresentaram menores teores de oligossacarídeos totais (2,744 e 3,064 g.100 g–1 de massa seca). As cultivares Tambaguro e Koji Amarela foram as que apresentaram teores de sacarose superiores a 6 g.100 g–1 de massa seca (6,327 e 6,162), enquanto que a única cultivar que apresentou um teor superior a 1 g.100g–1 de massa seca de amido foi a Tambaguro (1,191). As cultivares Koji Preta, Tamahomare, Tambaguro e BRS 267 foram estatisticamente superiores quando os 3 atributos (oligossacarídeos totais, sacarose e amido) foram avaliados conjuntamente, com o foco em sabor superior. As cultivares Koji Preta, Tamahomare, Tambaguro foram as melhores fontes genéticas indicadas para cruzamentos, pois não são tropicalizadas, enquanto a cultivar BRS 267 pode melhorar as qualidades sensoriais dos produtos processados a partir de soja. Por outro lado, a cultivar Late Giant, devido ao maior teor de oligossacarídeos, é uma fonte genética em potencial para produção de um alimento funcional à base de soja.RESUMO: Na soja, varios componentes, tais como acucares, aminoacidos, acidos orgânicos, sais inorgânicos, isoflavonas e saponinas estao relacionados com o sabor. Os acucares, a sacarose e o amido, podem melhorar o sabor e a textura da soja. O objetivo deste trabalho foi quantificar os teores desses compostos e dos oligossacarideos, em sementes de 28 genotipos/cultivares do Banco Ativo de Germoplasma da Embrapa Soja, que apresentam caracteristicas especiais para o melhoramento genetico. Os acucares e os oligossacarideos foram quantificados pela tecnica de cromatografia liquida de alto desempenho (CLAE) e o amido pela metodologia adaptada de Rickard e Behn (1987). Os genotipos PI 417.159 e F83-8119 apresentaram menores teores de oligossacarideos totais (2,744 e 3,064 g.100 g de massa seca). As cultivares Tambaguro e Koji Amarela foram as que apresentaram teores de sacarose superiores a 6 g.100 g?1 de massa seca(6,327 e 6,162), enquanto que a unica cultivar que apresentou um teor superior a 1 g.100g?1?1 de massa seca de amido foi a Tambaguro (1,191). As cultivares Koji Preta, Tamahomare, Tambaguro e BRS 267 foram estatisticamente superiores quando os 3 atributos (oligossacarideos totais, sacarose e amido) foram avaliados conjuntamente, com o foco em sabor superior. As cultivares Koji Preta, Tamahomare, Tambaguro foram as melhores fontes geneticas indicadas para cruzamentos, pois nao sao tropicalizadas, enquanto a cultivar BRS 267 pode melhorar as qualidades sensoriais dos produtos processados a partir de soja. Por outro lado, a cultivar Late Giant, devido ao maior teor de oligossacarideos, e uma fonte genetica em potencial para producao de um alimento funcional a base de soja. ABSTRACT: In soybeans, many components such as sugars, amino acids, organic acids, inorganic salts, saponins and isoflavones are related to the flavour. The sugars, sucrose and starch can improve the soybean flavour and texture. The present study aimed to quantify the contents of these compounds and also the oligosaccharides in the seeds from 28 genotypes/cultivars obtained from the Embrapa Soybean Germplasm Bank, that present special characteristics for genetic improvement programmes. The sugars and oligosaccharides were quantified by high-performance liquid chromatography (HPLC) and the starch by methodology adapted from Rickard e Behn (1987). The genotypes PI 417.159 and F83-8119 showed the lowest contents of total oligosaccharides (2.744 and 3.064 g.100 g DW). The cultivars Tambaguro and Koji Amarela showed sucrose levels above 6 g.100 g?1 DW (6.327 and 6.162), and the only cultivar with a starch content above 1 g.100 g?1 DW was Tambaguro (1.191). The cultivars Koji Preta, Tamahomare, Tambaguro and BRS 267 were statistically better when the 3 attributes (total oligosaccharides, sucrose and starch) were analysed together with a focus on better flavour. The cultivars Koji Preta, Tamahomare, Tambaguro were the best genetic sources for breeding because they have not been tropicalized, whilst the cultivar BRS 267 could improve the sensory qualities of processed soybean-based foods. On the other hand, on account of its higher oligosaccharide content, the cultivar Late Giant is a potential genetic source for the production of functional soybean-based foods.

Effects of a methanolic fraction of soybean seeds on the transcriptional activity of peroxisome proliferator-activated receptors (PPAR)

Since the anti-inflammatory, antidiabetic and hypolipidemic effects of soy isoflavones may be mediated by activation of peroxisome proliferator-activated receptors (PPAR), the present study investigated whether the methanolic fractions obtained from soybean seeds (E1) and soybean seed coats with hypocotyls (E2) could influence PPARalpha, PPARgamma and PPARbeta/delta transcriptional activity. The isoflavones from E1 and E2 were quantified by HPLC analysis. E1 and E2 were rich in isoflavones (daidzin, glycitin, genistin, malonyldaidzin, malonylglycitin, malonylgenistin, daidzein, glycitein, and genistein). Moreover, E1 and E2 showed no evidence of genetically modified material containing the gene CP4 EPSPS. To investigate PPAR transcriptional activity, human promonocytic U-937 cells were treated with E1 and E2 (200, 400, 800, and 1600 microg/mL), positive controls or vehicle. Data are reported as fold-activation of the luciferase reporter driven by the PPAR-responsive element. Dose-response analysis revealed that E1 and E2 induced the transcriptional activity of PPARalpha (P < 0.001), with activation comparable to that obtained with 0.1 mM bezafibrate (positive control) at 1600 microg/mL (4-fold) and 800 microg/mL (9-fold), respectively. In addition, dose-response analysis revealed that E1 and E2 activated PPARbeta/delta (P < 0.05), and the activation at 800 microg/mL (4- and 9-fold, respectively) was comparable to that of 0.1 mM bezafibrate (positive control). However, no effect on PPARgamma was observed. Activation of PPARalpha is consistent with the lipid-lowering activity of soy isoflavones in vivo, but further studies are needed to determine the physiological significance of PPARbeta/delta activation.