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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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A variety of plant protein sources have been evaluated in aquafeeds. Crambe meal (CM) has potential for inclusion in fish diets because of its nutritional composition. This study evaluated the apparent digestibility coefficient (ADC) of crambe meal and its potential to partially replace soybean meal (SM) protein in Nile tilapia Oreochromis niloticus diets. The ADC for dry matter, crude protein, ether extract, energy, amino acids, calcium and phosphorus of CM were assessed in fish (n = 80; 65.30 ± 5.32 g). Subsequently, an 80-day feeding trial was conducted with Nile tilapia (n = 140; 6.04 ± 0.25 g) randomly distributed in 20 experimental cages (70 L; seven fish cage-1) allocated in five circular tanks (1000 L) in a recirculation water system, to evaluate the effects of replacement of SM by CM (0, 6, 12, 18 and 24% in isonitrogenous and isoenergetic diets) on growth, blood parameters, fillet yield and proximal composition. The CM shows good digestibility of protein (0.824) and amino acids (0.844) by Nile tilapia and its inclusion in the diet does not affect carcass and fillet yield or proximal composition. Fish fed diets with 24.0% of the SM replaced by CM showed the worst weight gain and feed conversion rate. The protein efficiency ratio decreased in fish fed diets with 12.0, 18.0 and 24.0% of the SM replaced by CM. Hemoglobin, mean corpuscular hemoglobin concentration, total plasma protein, glucose and alanine aminotransferase enzyme activity trend to increase at highest levels of CM in the diet. In conclusion, CM has high digestibility of protein and amino acids for Nile tilapia. However, anti-nutritional factors present in untreated CM interfere on the growth and nutrient utilization of Nile tilapia.

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Rubber (Hevea brasiliensis) is a perennial plant crop grown in many parts of Africa, South East Asia, and South America, especially within the hot and humid climatic regions. Rubber seed, either as feed or food, is a useful raw material to produce edible oil and protein. Despite the huge quantity of rubber seeds produced in Nigeria and its potential as a protein source, rubber seeds still appear neglected and under-utilised as feed/food given its perception as inedible and toxic due to the high concentration of cyanogenic glycoside. Therefore, the quest for effective processing technique(s) that would enhance its food use application is very fitting. This current study was directed to determine the changes in anti-nutrient, phytochemical, and micronutrient contents of different processed rubber seed meals. Specifically, the rubber seeds underwent processing, which employed boiling and the combined action of boiling and fermentation methods that brought about three seed meal flour groups, i.e., raw (RRSM), boiled (BRSM), and fermented (FRSM) seed meals. These were subsequently analysed for anti-nutrient/phytochemical (oxalate, phytate, tannin, phenols, saponin, hydrogen cyanide (HCN), alkaloids, flavonoids, and trypsin inhibitors), and micronutrient (which involved minerals (magnesium, phosphorus, calcium, iron, zinc, potassium, sodium, manganese, lead, and selenium) and vitamin (vitamin B1, B2, B3, C, E, and beta carotene)) contents. The results showed that the processing methods used to achieve the RRSM, BRSM, and FRSM, reduced the anti-nutrients (phytate, tannin, and oxalate) below the acceptable limits, and the HCN below the toxic levels. Importantly, the processing methods herein have not yet succeeded in removing HCN in the (processed) rubber seed meals, but can be seen to be heading toward the right direction. The FRSM obtained significantly lower (p < 0.05) anti-nutrient/phytochemical, but significantly higher (p < 0.05) mineral contents, compared with the other groups (RRSM and BRSM), except for flavonoids that obtained a 30% increase over the BRSM. Some mineral and vitamin contents could be lost in the BRSM compared to the others (RRSM and FRSM) in this study. Additionally, the FRSM obtained higher vitamin contents, after those of RRSM. Overall, the combined action of boiling and fermentation should be recommended for the proper utilisation of rubber seed as food/feed.

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The development of functional foods containing probiotics has experienced a great boom in the last years, reflected by the increasing number of novel products available at the market, as well as by the well-documented extensive research, going beyond the traditional fermented dairy foods. However, to safe arrive to their target, the gut, microorganisms contained in food products have to overcome different barriers, both technological and physiological. Food processing might cause different types of damages on beneficial bacteria, which finally lead to a decrease of viability. In addition, once ingested, and before arriving to the gut, microorganisms are exposed to other food constituents, low pH and digestive juices, all of them constituting detrimental environments that can decrease their viability. For this reason, this review offers an updated state of the art on the microorganisms' response to the factors affecting their survival during drying techniques, storage and rehydration. Current strategies to overcome detrimental processing effects on bacterial viability are also reviewed, as well as the effect of food matrices on bacterial protection during food manufacturing and storage. The effect of probiotic microorganisms on the gut, and in particular on the intestinal microbiota is an issue of increasing interest in the last decades, and thus, special emphasis was put it on.

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Poultry fed on wheat-based diets regularly ingest wheat germ agglutinin (WGA) that has toxic effects in vitro on intestinal epithelial cells (IEC) obtained from 14-d-old broilers. Cytotoxicity and the potential role of 14 intestinal bacterial strains in the removal of bound lectins in epithelial cell cultures were investigated. Cytotoxicity was dependent on time and lectin concentration; the lethal dose (LD50) was 8.36 µg/ml for IEC exposed for 2 h to WGA. Complementary sugars to WGA were detected on the surface of one Enterococcus and 9 Lactobacillus strains isolated from poultry. These strains were evaluated as a lectin removal tool for cytotoxicity prevention. Incubation of lactic acid bacteria with WGA before IEC-lectin interaction caused a substantial reduction in the percentage of cell deaths. The protection was attributed to the amount of lectin bound to the bacterial surfaces and was strain-dependent. L. salivarius LET 201 and L. reuteri LET 210 were more efficient than the other lactic acid bacteria assayed. These results provide a basis for the development of probiotic supplements or cell-wall preparations of selected lactic acid bacteria intended to avoid harmful effects of a natural constituent of the grain in wheat-based diets.

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ABSTRACT The purpose of this study was to develop and improve protein concentration techniques for two industrial by-products with the potential for use in fish feed. In particular, we chemically characterized crambe meal and sunflower meal and their protein concentrates. Three different protein concentration methods were tested: isoelectric pH (pHi), acid pH and alkaline pH. For crambe and sunflower meals extraction using the pHi method was most efficient in terms of protein yield and crude protein content in the concentrates; this method also increased lysine and methionine content in the concentrates. The water holding capacity of the sunflower protein concentrate was greater than that of the crambe protein concentrate. The crambe protein concentrate had a foam-formation capacity of 15%, which stabilized at 6% after 90 minutes. The protein concentration method also reduced total phenolic content by approximately 50% in the concentrates compared with the meals. Therefore, we conclude that protein concentration using the pHi method is the most efficient technique for crambe and sunflower meals, and the use of this technique can decrease total phenolic compounds while improving meal quality for fish feeding.

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Este estudo avaliou a substituição parcial de farinhas de origem animal pelo farelo de tungue como fonte proteica no arraçoamento de carpa húngara. Os tratamentos compreenderam a inclusão de farelo de tungue in natura ou detoxificado (obtido após aplicação de tratamento químico ao farelo), e o tratamento referência consistiu de base proteica composta por farinha de carne e ossos suína e farinha de peixe. O período de alimentação foi de 63 dias. No decorrer de 30 dias experimentais não foi observada diferença em indicadores de crescimento entre os animais que consumiram as rações controle e com farelo de tungue tratado quimicamente, porém o consumo da ração com farelo de tungue in natura provocou redução no desempenho até o final do período experimental. Após 63 dias de arraçoamento, alguns indicadores de crescimento mostraram-se inferiores também para o tratamento que continha farelo de tungue tratado em relação ao controle. A análise bioquímica no plasma e no fígado revelou aumento de triglicerídeos, glicogênio, glicose e a utilização de outras fontes, possivelmente aminoácidos, como precursores energéticos na produção de energia quando os animais consumiram a dieta com farelo de tungue in natura em relação às demais, o que refletiu na menor concentração de proteína e na maior deposição de gordura na carcaça. Em relação à atividade de enzimas digestivas, tripsina apresentou atividade aumentada no tratamento com farelo de tungue in natura e protease ácida, quimotripsina, amilase e lipase não foram alteradas em nenhum dos tratamentos avaliados...

This study evaluated the partial replacement of animal meal by tung meal as protein source in feeding Hungarian carp. The treatments consisted of the inclusion of in natura or detoxified tung meal (obtained after chemical treatment applied to tung meal) as well as the reference treatment in which the protein basis was composed of meat and bone pork meal and fish meal. The feeding period was 63 days. During 30 experimental days no difference was observed in growth indicators among animals fed the control diet or with chemically treated tung meal, however, the consumption of diets with in natura tung meal caused reduced performance until the end of the experimental period. After 63 days of feeding, some growth indicators were also are lower for the treatment containing treated tung meal compared to control. Biochemical analysis in plasma and liver revealed increased triglycerides, glycogen, glucose and use of other sources, possibly amino acids, as precursors in the production of energy when animals consumed the diet with in nature tung meal in relation to others, which reflected in lower levels of protein and higher fat deposition in the carcass. Regarding the activity of digestive enzymes, trypsin showed increased activity in the treatment with in natura tung meal and acid protease, chymotrypsin, amylase and lipase were not changed in any of the treatments...

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Este estudo avaliou a substituição parcial de farinhas de origem animal pelo farelo de tungue como fonte proteica no arraçoamento de carpa húngara. Os tratamentos compreenderam a inclusão de farelo de tungue in natura ou detoxificado (obtido após aplicação de tratamento químico ao farelo), e o tratamento referência consistiu de base proteica composta por farinha de carne e ossos suína e farinha de peixe. O período de alimentação foi de 63 dias. No decorrer de 30 dias experimentais não foi observada diferença em indicadores de crescimento entre os animais que consumiram as rações controle e com farelo de tungue tratado quimicamente, porém o consumo da ração com farelo de tungue in natura provocou redução no desempenho até o final do período experimental. Após 63 dias de arraçoamento, alguns indicadores de crescimento mostraram-se inferiores também para o tratamento que continha farelo de tungue tratado em relação ao controle. A análise bioquímica no plasma e no fígado revelou aumento de triglicerídeos, glicogênio, glicose e a utilização de outras fontes, possivelmente aminoácidos, como precursores energéticos na produção de energia quando os animais consumiram a dieta com farelo de tungue in natura em relação às demais, o que refletiu na menor concentração de proteína e na maior deposição de gordura na carcaça. Em relação à atividade de enzimas digestivas, tripsina apresentou atividade aumentada no tratamento com farelo de tungue in natura e protease ácida, quimotripsina, amilase e lipase não foram alteradas em nenhum dos tratamentos avaliados.(AU)

This study evaluated the partial replacement of animal meal by tung meal as protein source in feeding Hungarian carp. The treatments consisted of the inclusion of in natura or detoxified tung meal (obtained after chemical treatment applied to tung meal) as well as the reference treatment in which the protein basis was composed of meat and bone pork meal and fish meal. The feeding period was 63 days. During 30 experimental days no difference was observed in growth indicators among animals fed the control diet or with chemically treated tung meal, however, the consumption of diets with in natura tung meal caused reduced performance until the end of the experimental period. After 63 days of feeding, some growth indicators were also are lower for the treatment containing treated tung meal compared to control. Biochemical analysis in plasma and liver revealed increased triglycerides, glycogen, glucose and use of other sources, possibly amino acids, as precursors in the production of energy when animals consumed the diet with in nature tung meal in relation to others, which reflected in lower levels of protein and higher fat deposition in the carcass. Regarding the activity of digestive enzymes, trypsin showed increased activity in the treatment with in natura tung meal and acid protease, chymotrypsin, amylase and lipase were not changed in any of the treatments.(AU)

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Associada à produção de biocombustíveis de fontes vegetais, há geração de vários coprodutos passíveis de utilização na nutrição animal, os quais necessitam de estudos minuciosos para aplicabilidade amplae segura. O farelo de crambe é um coproduto ainda pouco conhecido e são necessários estudos para melhor avaliar seu potencial nutricional. Neste contexto, o estudo foi conduzido com o objetivo de mensurar grupos químicos de interesse (nutrientes e antinutrientes) e digestibilidade proteica in vitro do farelo de crambe nas formas in natura e reduzida em antinutrientes. Para retirar antinutrientes foram aplicadas soluções ácida (adição de ácido sulfúrico concentrado à água até pH 1,0) e alcoólica (etanolcomercial 92,8º) sobre o farelo in natura. Os resultados demonstraram que o tratamento químico elevou o teor de fibra e matéria mineral e reduziu a concentração de proteína bruta, aminoácidos, gordura, cálcio e fósforo assim como compostos fenólicos, taninos (totais, condensados, hidrolisáveis) e ácidofítico. Embora o tratamento químico tenha alterado o balanço da maioria dos constituintes de interessenutricional, o seu efeito não foi observado na digestibilidade proteica in vitro. As característicasnutricionais e antinutricionais obtidas para este farelo podem colaborar no indicativo de uma fonte proteica alternativa para a nutrição animal.(AU)

Associated with biofuels production from plant sources, there is generation of several byproducts suitable to use in animal nutrition, which requires careful study for wide and safe applicability. Crambemeal is a byproduct still poorly understood and studies are needed to better assess their nutritional potential. In this context, the present study was carried out with the aim of measuring the chemical groups of interest (nutrients and antinutrients) and in vitro protein digestibility of crambe meal in nature and reduced antinutrients forms. For removal antinutrients were applied acidic (adding concentrated sulfuric acid to water until pH 1.0) and alcoholic (commercial ethanol 92.8º) solutions on in naturemeal. The results showed that chemical treatment increased the fiber and ash content and reduced the crude protein, amino acids, fat, calcium and phosphorus content as well as phenolic compounds, tannins (total, condensed and hydrolysable) and phytic acid. Although the chemical treatment has changed the balance of the constituents of most of nutritional interest, its effect was not observed in in vitroprotein digestibility. The nutritional and antinutritional character obtained for this meal can collaborate in indicative of an alternative protein source for animal nutrition.(AU)

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Esse estudo teve como objetivo realizar a caracterização química das hortaliças não-convencionais conhecidas como ora-pro-nobis (Pereskia aculeata e Pereskia grandifolia). Foi determinada a composição centesimal e mineral, bem como os teores de vitamina C, carotenoides totais, -caroteno, licopeno, ácido oxálico, nitrato, saponinas, compostos fenólicos e o inibidor da tripsina da farinha das folhas destas plantas. P. grandifolia apresentou os maiores teores de proteínas e de lipídios e os menores de cinzas e fibra alimentar total, que P. aculeata. Já P. grandifolia apresentou maior teor de cálcio, e para os demais minerais a P. aculeata se destacou. A P. aculeata também apresentou os maiores teores de vitamina C e -caroteno. Quanto aos carotenoides totais e o ácido oxálico P. grandifolia apresentou maiores níveis, sendo que na P. aculeata não foi detectado o licopeno, mas os teores de nitratos foram 15 vezes superiores ao de P. grandifolia, apresentando também maior inibição da tripsina. Os teores de saponinas foram semelhantes nas duas amostras de farinhas analisadas. Conclui-se que as folhas destas cactáceas são importantes fontes de proteínas, fibras, minerais (principalmente o cálcio e o ferro) e de compostos bioativos. Mesmo sendo detectados antinutrientes nas farinhas, seu consumo diário não será suficiente para causar malefícios à saúde humana.

The aim of this study was to chemistry characterize the non-conventional vegetable known as ora-pro-nobis (Pereskia grandifolia and Pereskia aculeata). The proximate and mineral compositions were determined as well as vitamin C, total carotenoids, -carotene, lycopene, oxalic acid, nitrate, saponins, phenolic compounds and the trypsin inhibitor from flour produced from the leaves of these plants. P. grandifolia showed higher levels of proteins and lipids and lower ash and total dietary fiber than P. aculeata. The P. grandifolia showed greater calcium concentrations while P. aculeata presented higher concentrations of the other minerals. The P. aculeata also showed the highest levels of vitamin C and -carotene. Regarding total carotenoids and oxalic acid the P. grandifolia showed higher levels, while in P. aculeata lycopene was not detected, but nitrate levels were 15 times higher than in P grandifolia, also showing greater trypsin inhibition. The saponin contents were similar in the two flour samples analyzed. It was concluded that these plants are important sources of proteins, fibers, minerals (especially calcium and iron) and bioactive compounds. Although antinutrients were found in flour, it is suggested that these cacti can enrich the diet with nutrients, since daily intake does not present harm to human health.

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Associada à produção de biocombustíveis de fontes vegetais, há geração de vários coprodutos passíveis de utilização na nutrição animal, os quais necessitam de estudos minuciosos para aplicabilidade amplae segura. O farelo de crambe é um coproduto ainda pouco conhecido e são necessários estudos para melhor avaliar seu potencial nutricional. Neste contexto, o estudo foi conduzido com o objetivo de mensurar grupos químicos de interesse (nutrientes e antinutrientes) e digestibilidade proteica in vitro do farelo de crambe nas formas in natura e reduzida em antinutrientes. Para retirar antinutrientes foram aplicadas soluções ácida (adição de ácido sulfúrico concentrado à água até pH 1,0) e alcoólica (etanolcomercial 92,8º) sobre o farelo in natura. Os resultados demonstraram que o tratamento químico elevou o teor de fibra e matéria mineral e reduziu a concentração de proteína bruta, aminoácidos, gordura, cálcio e fósforo assim como compostos fenólicos, taninos (totais, condensados, hidrolisáveis) e ácidofítico. Embora o tratamento químico tenha alterado o balanço da maioria dos constituintes de interessenutricional, o seu efeito não foi observado na digestibilidade proteica in vitro. As característicasnutricionais e antinutricionais obtidas para este farelo podem colaborar no indicativo de uma fonte proteica alternativa para a nutrição animal.

Associated with biofuels production from plant sources, there is generation of several byproducts suitable to use in animal nutrition, which requires careful study for wide and safe applicability. Crambemeal is a byproduct still poorly understood and studies are needed to better assess their nutritional potential. In this context, the present study was carried out with the aim of measuring the chemical groups of interest (nutrients and antinutrients) and in vitro protein digestibility of crambe meal in nature and reduced antinutrients forms. For removal antinutrients were applied acidic (adding concentrated sulfuric acid to water until pH 1.0) and alcoholic (commercial ethanol 92.8º) solutions on in naturemeal. The results showed that chemical treatment increased the fiber and ash content and reduced the crude protein, amino acids, fat, calcium and phosphorus content as well as phenolic compounds, tannins (total, condensed and hydrolysable) and phytic acid. Although the chemical treatment has changed the balance of the constituents of most of nutritional interest, its effect was not observed in in vitroprotein digestibility. The nutritional and antinutritional character obtained for this meal can collaborate in indicative of an alternative protein source for animal nutrition.

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In order to confirm the traditional use of Baccharis trimera (Less.) DC., Asteraceae, for the reduction of weight, plant extracts were evaluated on the activity of pancreatic lipase (PL), an enzyme responsible for hydrolysis of triacylglycerols in the diet for its subsequent absorption. The aqueous and infused extracts did not show inhibitory activity on the PL, the ethanol inhibited 16 percent (66 ALI/g) and methanol extract inhibited 78 percent (241 ALI/g). The methanol extract of B. trimera (MEB) was subjected to a wash with decreasing solvent polarity (n-hexane, ethyl acetate and methanol) and only the methanol fraction inhibited the lipase by 72 percent (230 ALI/g). We evaluated the MEB and infused inhibitory activity on the enzymes α-amylase and α and β-glycosidases. The α-amylase was not inhibited by any of the extracts, the enzyme α-glucosidase was inhibited by both extracts in the same proportion (46.9±0.1) and β-glucosidase was inhibited by 73 percent by the methanol extract and 65 percent by the infused. We also evaluated the presence of anti-nutrients. We detected the presence of saponins, polyphenols and trypsin inhibitors in the two samples. Tests performed in vivo can assess at which therapeutic concentration the presence of these anti-nutrients can be harmful to health.

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OBJETIVO: Analisar os componentes químicos e antinutrientes antes e após torrefação da amêndoa de chichá da espécie Sterculia striata A. St. Hill & Naudin, oriunda de Corrente, Piauí. MÉTODOS: Foram realizadas análises: centesimal, perfil de ácidos graxos, antinutrientes (taninos, inibidor de tripsina, inibidor de amilase, lectina, fitatos), compostos fenólicos e atividade de peroxidase e polifenoloxidase. RESULTADOS: Os resultados da análise centesimal da amêndoa crua e torrada foram: lipídeos de 25,1 por cento e 26,2 por cento, carboidratos de 44,4 por cento e 45,6 por cento, proteína de 20,8 por cento e 22,1 por cento, cinzas de 3,7 por cento e 4,0 por cento, fibra alimentar total de 12,3 por cento e 10,4 por cento, respectivamente. Nas amêndoas cruas e torradas não foram encontradas lectinas, taninos, inibidores de tripsina e alfa-amilase. Verificou-se a ausência de peroxidase e polifenoloxidase e conteúdo de compostos fenólicos de 107,7mg/100g e 108,9mg/100g para amêndoas cruas e torradas, respectivamente. CONCLUSÃO: A torrefação realizada a 205ºC por 11 minutos diminuiu o teor de fitatos de 10,6mg/g para 5,5mg/g. Por fim, as amêndoas de chichá, cruas e torradas, apresentam alto teor de proteínas, fibras, ácidos graxos monoinsaturados e saturados.

OBJECTIVE: This study analyzed the chemical components and antinutrients present in raw and roasted chichá almonds from the species Sterculia striata A. St. Hill & Naudin harvested in Corrente, Piauí. METHODS: The following were determined: percent composition, fatty acid profile, antinutrients (tannins, trypsin inhibitor, amylase inhibitor, lectin, phytates), phenolic compounds and peroxidase and polyphenol oxidase activities. RESULTS: The percentage composition of the raw and lipid almonds were respectively: 25.1 percent and 26.2 percent fats, 44.4 percent and 45.6 percent carbohydrates, 20.8 percent and 22.1 percent protein, 3.7 percent and 4.0 percent ashes, and 12.3 percent and 10.4 percent total fiber. Neither raw nor roasted almonds contained lectins, tannins, trypsin inhibitors, alpha-amylase, peroxidase and polyphenol oxidase. Contents of phenolic compounds were 107.7mg/100g and 108.9mg/100 for the raw and roasted almonds, respectively. CONCLUSION: Roasting at 205ºC for 11 minutes reduced phytate content from 10.6mg/g to 5.5mg/g. Raw and roasted chichá almonds have a high content of proteins, fibers and monounsaturated and saturated fatty acids.

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El objetivo de este artículo fue investigar la presencia de los factores antinutricionales en el arroz pilado crudo, tales como inhibidor de la tripsina, la lectina y el ácido fítico. El estudio es parte del proyecto de investigación de la equivalencia sustancial del arroz mejorado genéticamente AS 10-7-6 y CPM 10-4-6, desarrollado por el Centro de Investigaciones de Biología Molecular y Celular de la Universidad de Costa Rica, CIBCM, en Costa Rica. La metodología utilizada fue revisión de literatura, disponible en revistas nacionales e internacionales y consulta a expertos. Se encontró que la detección de dichos antinutrientes en el arroz pilado es muy baja en arroz crudo y es aún menor en el arroz cocido, ya que la lectina y el inhibidor de la tripsina son sensibles al calor y se inactivan al cocinar el alimento. En estudios realizados el arroz mejorado genéticamente llamado Libertylink, no se encontraron diferencias en el contenido de ácido fítico al compararlo con el par convencional. Además, se encontró que el inhibidor de la tripsina sólo está presente en la granza; la lectina no fue detectada en ninguna de las presentaciones del arroz. Por lo que al considerar la información bibliográfica y los resultados del arroz LibertyLink, se concluye que la presencia de antinutrientes es baja o ninguna, en el arroz pilado de las líneas mejoradas genéticamente en estudio.

The purpose of this study was to research the presence of anti-nutrient factors such as the trypsin inhibitor, lectin and phytic acid all in raw, polished rice. This review is part of a larger research project on the substantial equivalence of AS 10-7-6 and CPM 10-4-6, genetically-modified rice developed by the Cellular and Molecular Biology Research Center (CIBCM) at the University of Costa Rica. The methodology used was a review of the literature both in national as well as in international journals and also experts´ opinion. Our results show that detection of these anti-nutrient factors in rice is low and it is very low in polished rice; the reason is that lectin and trypsin inhibitors are heat-sensitive and they are deactivated when cooked. Some studies done on genetically-modified Libertylink rice found no difference in phytic acid content when compared to non-modified rice. The trypsin inhibitor is detected only on the embryo and bran layers; lectin was not detected in any of the different rice presentations. In conclusion, according to the review done in the literature as well as the study done on Libertylink rice, it can be said that the presence of anti-nutrients in rice is expected to be low or absent in genetically-modified rice lines.

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RESUMO

O feijão representa a principal fonte de proteínas para as populações de baixa renda, todavia a digestibilidade dessas proteínas é relativamente baixa. Por isto, os programas de melhoramento genético vêm trabalhando em busca de novas linhagens com níveis protéicos mais elevados. Assim, com a finalidade de fornecer informações aos melhoristas, neste trabalho foram analisadas 21 linhagens de feijão (Phaseolus vulgaris L.), quanto à composição centesimal e mineral, digestibilidade protéica, compostos fenólicos e inibidor de tripsina. O delineamento experimental utilizado foi o inteiramente casualizado, com 21 tratamentos (linhagens) e três repetições. O teor de proteína bruta variou de 22,34 a 36,28 g/100 g de matéria seca (MS); o de fibra detergente neutro de 7,56 a 20,91g/100 g MS; o de extrato etéreo de 0,53 a 2,55 g/100 g MS e o de cinzas de 2,97 a 4,87 g/100 g MS. Os teores, em g/100 g MS, de P, K, Ca, Mg e S variaram de 0,45 a 0,72; 1,51 a 2,48; 0,03 a 0,28; 0,18 a 0,34 e 0,28 a 0,45, respectivamente. Já os teores de Cu, Mn, Zn e Fe, em mg/kg MS, variaram de 11,37 a 17,73; 14,93 a 28,90; 36,67 a 69,90 e 71,37 a 126,90, respectivamente. A digestibilidade protéica in vitro variou de 18,03 por cento a 48,32 por cento. Os teores de compostos fenólicos variaram de 0,28 a 1,08 mg de ácido tânico/100 g MS e os de inibidor de tripsina de 59,93 a 151,07UTI/mg MS. Entre as linhagens com maiores teores protéicos a "ESAL 569" (bege com rajas marrons) apresentou a maior digestibilidade protéica e também níveis consideráveis de minerais. A "P-180" (bege com rajas marrons) ficou entre as linhagens com teores mais elevados de proteína bruta e entre as de maiores digestibilidades, além de ter apresentado teores elevados para a maioria dos minerais. Não foi observada nenhuma relação entre a digestibilidade da proteína e os teores de compostos fenólicos e inibidor de tripsina.

Bean represents the main source of proteins for the low income populations, though the digestibility of those proteins is relatively low. Consequently, the programs of plant genetic breeding have been working on the search for new lines with higher protein levels. Thus, with the purpose of supplying information to the researchers, in this work 21 bean (Phaseolus vulgaris L.) lines were analyzed for the centesimal and mineral composition, protein digestibility, phenolic compounds and trypsin inhibitor. The entirely randomized experimental design was used with 21 treatments (lines) and three repetitions. All values were within the following ranges: 22.34 to 36.28g of crude protein/100g of dry matter (DM); 7.56 to 20.91g of neutral detergent fiber/100g DM; 0.53 to 2.55g of fat/100g DM and 2.97 to 4.87g of ashes/100g DM. The levels, in g/100g DM, of P, K, Ca, Mg and S varied from 0.45 to 0.72; 1.51 to 2.48; 0.03 to 0.28; 0.18 to 0.34 and 0.28 to 0.45, respectively. Regarding Cu, Mn, Zn and Fe, the levels in mg/kg DM, varied from 11.37 to 17.73; 14.93 to 28.90; 36.67 to 69.90 and 71.37 to 126.90, respectively. The in vitro protein digestibility varied from 18,03 percent to 48,32 percent. The levels of phenolic compounds varied from 0.28 to 1.08mg of acid tanic/100g DM and the one of trypsin inhibitor from 59.93 to 151.07 TIU/mg DM. Among the lines with higher protein contents, "ESAL 569" (beige with brown stripe) presented the largest protein digestibility and also considerable levels of minerals. "P-180" (beige with brown stripe) was one of the lines with higher crude protein contents and digestibilities, and also presented high levels for most of the minerals. No relationship between protein digestibility and the contents of phenolic compounds and trypsin inhibitor was observed.