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Braz. j. pharm. sci ; 49(2): 275-283, Apr.-June 2013. ilus, graf, tab
Article in English | LILACS | ID: lil-680638


Phytic acid is a natural compound widely used as depigmenting agent in galenic cosmetic emulsions. However, we have observed experimentally that phytic acid, when heated to 150 ºC for around one hour, shows evidence of thermal decomposition. Few studies investigating this substance alone with regard to its stability are available in the literature. This fact prompted the present study to characterize this species and its thermal behavior using thermal analysis (TG/DTG and DSC) and to associate the results of these techniques with those obtained by elemental analysis (EA) and absorption spectroscopy in the infrared region. The TG/DTG and DSC curves allowed evaluation of the thermal behavior of the sample of phytic acid and enabled use of the non-isothermal thermogravimetric method to study the kinetics of the three main mass-loss events: dehydration I, dehydration II and thermal decomposition. The combination of infrared absorption spectroscopy and elemental analysis techniques allowed evaluation of the intermediate products of the thermal decomposition of phytic acid. The infrared spectra of samples taken during the heating process revealed a reduction in the intensity of the absorption band related to O-H stretching as a result of the dehydration process. Furthermore, elemental analysis results showed an increase in the carbon content and a decrease in the hydrogen content at temperatures of 95, 150, 263 and 380 °C. Visually, darkening of the material was observed at 150 °C, indicating that the thermal decomposition of the material started at this temperature. At a temperature of 380 °C, thermal decomposition progressed, leading to a decrease in carbon and hydrogen. The results of thermogravimetry coupled with those of elemental analysis allow us to conclude that there was agreement between the percentages of phytic acid found in aqueous solution. The kinetic study by the non-isothermal thermogravimetric method showed that the dehydration process occurred in two stages. Dehydration step I promoted a process of vaporization of water (reaction order of zero), whereas dehydration step II showed an order of reaction equal to five. This change in reaction order was attributed to loss of chemically bonded water molecules of phytic acid or to the presence of volatile substances. Finally, the thermal decomposition step revealed an order of reaction equal to one. It was not possible to perform the kinetic study for other stages of mass loss.

O ácido fítico é um composto natural muito utilizado como despigmentante em emulsões cosméticas magistrais. No entanto, observou-se experimentalmente que o ácido fítico, quando aquecido a 150 °C durante cerca de uma hora, mostra evidências de decomposição térmica e que poucos estudos envolvendo essa espécie, isoladamente quanto a sua estabilidade, estão disponíveis na literatura. Esse fato motivou o estudo de caracterização e de comportamento térmico dessa espécie, empregando a análise térmica (TG/DTG e DSC) e associando os resultados obtidos com aqueles de análise elementar (AE) e espectroscopia de absorção na região do infravermelho. As curvas TG/DTG e DSC permitiram avaliar o comportamento térmico da amostra de ácido fítico e, com isso, foi possível estudar, pelo método termogravimétrico não isotérmico, a cinética dos três principais eventos de perda de massa, o de desidratação I, desidratação II e de decomposição térmica. A associação das técnicas de espectroscopia de absorção no infravermelho e análise elementar permitiu avaliar os produtos intermediários da decomposição térmica do ácido fítico. Os espectros no infravermelho de amostras isoladas durante o aquecimento evidenciaram a diminuição de intensidade da banda de absorção relativa ao estiramento do grupo O-H como consequência do processo de desidratação. Também, os resultados de análise elementar indicaram que nas temperaturas de 95, 150 e 263 ºC houve aumento no teor de carbono e diminuição do teor de hidrogênio. Visualmente, observou-se o escurecimento do material a 150 ºC, indicando que a decomposição térmica do material iniciou-se nessa temperatura. Na temperatura de 380 ºC, a diminuição do teor de carbono e hidrogênio foi devido ao avanço do processo de decomposição térmica. Os resultados da termogravimetria juntamente com aqueles da análise elementar permitiram concluir que há concordância entre as percentagens de ácido fítico encontrado na solução aquosa. O estudo cinético pelo método termogravimétrico não isotérmico mostrou que o processo de desidratação ocorreu em duas etapas. Na etapa I da desidratação ocorreu um processo de vaporização de água (ordem de reação igual a zero). Na etapa II da desidratação foi encontrada uma ordem de reação igual a cinco. Essa mudança na ordem de reação foi atribuída à perda de moléculas de água quimicamente ligada, ao ácido fítico ou à presença de substâncias voláteis. Finalmente, na etapa de decomposição térmica foi observado que a ordem da reação foi igual a um. Para as outras etapas de perda de massa não foi possível a realização do estudo cinético.

Differential Thermal Analysis/classification , Phytic Acid/analysis , Cosmetic Stability , Dehydration/classification , Emulsions/pharmacokinetics
Braz. j. microbiol ; 44(1): 317-323, 2013. ilus
Article in English | LILACS | ID: lil-676905


Phytate is the primary storage form of phosphate in plants. Monogastric animals like poultry, pigs and fishes have very low or no phytase activities in their digestive tracts therefore, are incapable to efficiently utilize phytate phosphorus from the feed. Phytase from microbial sources are supplemented to feedstuff of these to increase the uptake of phytate phosphorus. In the present work efforts were made to isolate and characterize proficient phytase producing fungi from soil. Phytase producing fungi were isolated using phytate specific medium. Fungal isolates were selected according to their higher phytase activities. These isolates were further characterized and identified by morphological and microscopic analysis and confirmed by amplification of 18S rRNA gene, using specific primers. This gene was subsequently sequenced and phylogenetic affiliations were assigned. Fungal isolates were identified as various species of Aspergillus. Phytases from these fungi could be utilized as a feed additive in poultry and swine industries.

Phytic Acid/analysis , Aspergillus/genetics , Aspergillus/isolation & purification , Edible Grain/enzymology , Edible Grain/genetics , Phosphates/analysis , Genes, Fungal , Heavy Ions , Inositol , Food Samples , Hydrolysis , Methods
Arch. latinoam. nutr ; 62(2): 103-111, jun. 2012. ilus, tab
Article in English | LILACS | ID: lil-710610


The objective of this study was to evaluate iron bioavailability of maize genotypes, and analyze the correlation between in vitro and in vivo methods. Dialysable iron was analyzed in 13 genotypes from which 5 were selected for the biological assay. Mean iron content of the genotypes (n=13) was 17.93±2.93 mg kg-1. Phytate varied from 0.77% to 1.03%; phytate: iron molar ratio from 30.64 to 55.41; and soluble iron from 13.17 to 39.63%. The highest value for dialysable iron was 19.14%. In the biological assay, the control group, that received ferrous sulphate, did not present significant difference between the genotypes for Hb gain, Hb gain per gram of iron consumed and HRE. Hb gain did not present a significant correlation with in vitro assay. However, there were positive correlations varying from 0.653 to 0.809. The maize genotypes evaluated presented a good bioavailability since the genotypes showed the same result in hemoglobin gain than control group.

Biodisponibilidade de ferro de diferentes genótipos de milho desenvolvidos em programa de melhoramento genético: estudos in vitro e in vivo. O objetivo deste estudo foi avaliar a biodisponibilidade do ferro de genótipos de milho e analisar a correlação entre métodos in vitro e in vivo. Ferro dialisável foi analisado em13 genótipos, a partir do qual 5 foram selecionados para o ensaio biológico. A média de teor de ferro dos genótipos (n= 13) foi 17,93 ± 2,93 mg kg-1. O teor de fitato variou de 0,77% a 1,03%; razão molar fitato:ferro de 30,64 a 55,41; e ferro solúvel de 13,17 a 39,63%.O valor mais alto para o ferro dialisável foi 19,14%. No ensaio biológico, o grupo controle, que recebeu sulfato ferrso, não apresentou diferença significativa entre os genótipos no ganho Hb, ganho de Hb por grama de ferro consumido e HRE. Ganho de Hb não apresentou correlação significativa com o ensaio in vitro. No entanto, houve correlações positivas variando de 0,653 a 0,809. Os genótipos de milho avaliados apresentaram uma boa biodisponibilidade uma vez que os genótipos apresentaram o mesmo resultado quanto ao ganho de hemoglobina em relação ao grupo controle.

Animals , Male , Rats , Anemia, Iron-Deficiency/prevention & control , Food, Fortified/analysis , Iron, Dietary/pharmacokinetics , Phytic Acid/analysis , Plants, Genetically Modified/chemistry , Zea mays/genetics , Anemia, Iron-Deficiency/diet therapy , Biological Availability , Breeding , Biological Assay/methods , Dialysis , Genotype , Hemoglobins/metabolism , Iron, Dietary/analysis , Rats, Wistar , Spectrophotometry, Atomic , Zea mays/chemistry
Arch. latinoam. nutr ; 61(2): 135-142, jun. 2011. ilus, graf, mapas
Article in English | LILACS | ID: lil-659121


In this study the chemical composition and iron bioavailability of hull and hull-less soybean flour from the new cultivar UFVTN 105AP was evaluated. The hemoglobin depletion-repletion method was used in Wistar rats. Soybean hull flour presented 37% more total dietary fiber and higher content of iron than hull-less soybean flour. The phytate:iron molar ratio, however, was 2-fold lower in the soybean hull flour in compared to the hull-less soybean flour. Animals fed soybean hull flour presented hemoglobin gains similar to those of the control diet group (p>0.05). The Relative Biological Values of hull and hull-less soybean flour were 68.5% and 67.1%, respectively, compared to the control group. Heat-treated soybean hull flour (150ºC/30 minutes) showed high content of iron and low phytate, which favors the iron bioavailability. Thus, the soybean hull flour is a better source of dietary fiber and iron than hull-less soybean flour at comparable bioavailabilities.

Neste estudo foram avaliadas a composição química e a biodisponibilidade de ferro das farinhas de soja com e sem casca do novo cultivar UFVTN 105AP. O método usado foi de depleção-repleção de hemoglobina em ratos Wistar. A farinha de soja com casca apresentou 37% a mais de fibra alimentar e maior teor de ferro (p 0,05). O Valor Relativo de Biodisponibilidade (VRB) da farinha de soja com casca e sem casca foram 68,5% e 67,1%, respectivamente, em relação ao sulfato ferroso (100%). A farinha de soja com casca submetida ao tratamento térmico (150ºC/30 minutos) apresentou maior teor de ferro e reduzido conteúdo de fitato, favorecendo a biodisponibilidade de ferro. Assim, a farinha de soja com casca apresentou melhor fonte de fibra alimentar e ferro do que a farinha de soja sem casca de comparável biodisponibilidade.

Animals , Male , Rats , Diet , Ferrous Compounds/chemistry , Flour/analysis , Hot Temperature , Iron, Dietary/pharmacokinetics , Soybeans/chemistry , Biological Availability , Dietary Fiber , Iron/chemistry , Phytic Acid/analysis , Rats, Wistar
Rev. nutr ; 21(3): 323-328, maio-jun. 2008. tab
Article in Portuguese | LILACS | ID: lil-487553


OBJETIVO: Este estudo objetivou quantificar o teor de ácido cianídrico em folhas de mandioca, que receberam tratamento prévio antes da secagem, e a concentração de ácido fítico na multimistura submetida à cocção úmida. MÉTODOS: Utilizou-se a multimistura produzida pela Pastoral da Criança da cidade de Pelotas (RS), constituída por: farelos de trigo (30 por cento) e arroz (30 por cento): farinhas de milho (15 por cento) e trigo (10 por cento); pós de casca de ovo (5 por cento), de folha de mandioca (5 por cento) e de sementes (5 por cento, abóbora ou girassol). Foi realizada orientação ao fornecedor da folha de mandioca sobre a forma recomendada de preparo antes da secagem. RESULTADOS: O conteúdo de ácidos cianídrico e fitatos no suplemento alimentar foram respectivamente de e 35.90mg.100-1. CONCLUSÃO: Verificou-se que a mudança na forma de secagem das folhas de mandioca foi eficiente para a redução de glicosídeos cianogênicos, e que o processo de torrefação dos ingredientes foi suficiente para produzir a redução de ácido fítico da multimistura aos níveis preconizados pela legislação, não sendo observadas diferenças estatisticamente significantes quando comparadas as amostras que também foram tratadas com calor úmido.

OBJECTIVE: The objective of this study was to quantify the amount of hydrogen cyanide in cassava leaves that were treated before drying and the concentration of phytic acid in a multimixture submitted to wet cooking. METHODS: The multimixture produced by the Pastoral da Criança of the city of Pelotas (RS) consisting of wheat flour (30 percent), rice flour (30 percent), corn flour (15 percent), wheat (10 percent), egg shell powder (5 percent), cassava leaves (5 percent) and pumpkin or sunflower seeds (5 percent) was used. The supplier was advised on how to process the cassava leaves before drying them. RESULTS: The hydrogen cyanide and phytic acid contents of the feeding supplement are and 35.90mg.100-1 respectively. CONCLUSION: Changing the way the cassava leaves were dried was efficient to reduce the amount of cyanogenic glucosides. The cooking process of the ingredients was enough to reduce the phytic acid content in the multimixture to the levels recommended by the legislation. Significant statistical differences were not observed between these samples and those treated with moist heat.

Phytic Acid/analysis , Hydrogen Cyanide/analysis , Dietary Supplements/analysis
Electron. j. biotechnol ; 9(1)Jan. 2006.
Article in English | LILACS | ID: lil-432458


Cassava pulp was fermented with pure strains of Saccharomyces cerevisae and two bacteria namely Lactobacillus delbruckii and Lactobacillus coryneformis for 3 days. The squeezed liquid from the fermented pulp was used to ferment cassava peels for 7 days. Analysis of the dried fermented peels revealed that there was a significant (P < 0.05) increase in the protein content of the cassava peels fermented with squeezed liquid from the inoculated cassava pulp (21.5%) when compared with the unfermented cassava peel (8.2%). Moreover, the treatment equally brought about a significant (P < 0.05) decrease in the cyanide (6.2 mg/kg) and phytate content (789.7 mg/100g) when compared with the unfermented cassava peels, which had 44.6 mg/kg cyanide and 1043.6 mg/100g phytate. The fermented cassava peels could be a good protein source in livestock feeds.

Lactobacillus/physiology , Manihot/metabolism , Plant Proteins/biosynthesis , Saccharomyces cerevisiae/physiology , Phytic Acid/analysis , Culture Media , Cyanides/analysis , Fermentation , Manihot/chemistry , Food Handling/methods , Plant Proteins/analysis
Article in English | IMSEAR | ID: sea-41416


The amount of phytate and total dietary fiber of 6 popular tropical fruits eaten by diabetic patient residing in Bangkok were studied. They were dragon fruit, durian, guava, longan, mango, and pineapple. Fruit containing the highest content of total dietary fiber was guava which had about 2.7%. Longan contained the lowest fiber content equal to 0.19%. The highest content of phytate was found in pineapple about 0.09% and the lowest content was in longan about 0.037%. It was noticed that longan contained the lowest total dietary fiber and the lowest phytate content.

Diet, Diabetic , Dietary Fiber/analysis , Fruit/chemistry , Humans , Phytic Acid/analysis , Thailand
Arch. latinoam. nutr ; 51(3): 276-283, sep. 2001.
Article in Portuguese | LILACS | ID: lil-333627


The objective of this study was to evaluate the effect of the soaking step and the domestic processing of the common bean, on the chemical composition, the levels of phytate, tannin, starch and flatulence factors by utilizing the follows treatments: raw bean (FC), freeze-dried cooked unsoaked bean (FCSM), freeze-dried cooked bean without the non-absorbed soaking water (FCSAM), freeze-dried cooked bean with the non-absorbed soaking water (FCCAM) and the soaking water (AM). The beans were soaking for a period for 16 hours in the proportion 3:1 (water:beans) at room temperature. The effect of the phytates and tannins on the net protein efficiency ratio (NPR) and protein digestibility using male Wistar rats were studied. A decrease in the phytate content of the beans (85) with use of soaking was observed. In the case of the tannin content, only the cooking of the beans promoted high decomposition (84). In the (FCSAM) treatment a decrease in the raffinose (25.0), stachiose (24.8), verbascose (41.7) and starch (26.8) contents was observed. Diets containing casein (control), casein plus the soluble solids obtain from the soaking water showed no significant difference (p > 0.05) for the NPR, as well as for the different bean treatments, although these showing lower values. The treatment (FCSM) showed the higher digestibility (74.3 +/- 5.8) of the bean treatments, the casein diets showing 94.6 +/- 0.9. The reduction of the phytates, tannin, starch contents and flatulence factors in the common bean was most effective when the soaking water not absorbed was discarded (FCSAM).

Animals , Male , Rats , Carbohydrates , Flatulence , Food Handling/methods , Phaseolus , Phytic Acid/analysis , Cooking , Digestion , Glucosides/analysis , Nutritive Value , Oligosaccharides/analysis , Raffinose , Rats, Wistar , Starch , Tannins
Specialist Quarterly. 1999; 15 (3): 225-228
in English | IMEMR | ID: emr-52822


The zinc has been determined by Neutron Activation Analysis while phytate by spectrophotometric method in some Pakistani cereal grains. The zinc : phytate ratio found is more than 40:1 in all cereal grains which is far more than the suggested binding ratio of 4:1. Therefore, bioavaliability of zinc from Pakistani cereal grains is more than sufficient and no deficiency can be encountered due to bioavailability of zinc. The only deficiency of zinc which could happen will be due to the pathological conditions

Phytic Acid/analysis , Neutron Activation Analysis , Biological Availability , Spectrophotometry , Edible Grain/chemistry
Arch. latinoam. nutr ; 48(2): 169-74, jun. 1998. tab, graf
Article in Portuguese | LILACS | ID: lil-226059


Sementes de soja cultivar BR 16 foram submetidas à maltagem por 24 e 48 horas e à extrusao obtendo-se flocos, os quais foram moídos e utilizados na fabricaçao de biscoitos. Flocos e biscoitos foram analisados sensorialmente. O efeito da maltagem e da extrusao foram também avaliados em relaçao às características químico-nutricionais. A composiçao em macro nutrientes nao apresentou alteraçoes acentuadas mostrando pequeno decréscimo nos teores de carboidratos totais e discreto aumento relativo nos teores de carboidratos totais e discreto aumento relativo nos teores de lipídeos no produto maltado. Dentre os fatores antinutricionais, os inibidores de tripsina apresentaram queda de 50 por cento após 24h de maltagem e desaparecimento após a extrusao. Os teores de ácido fítico nao sofreram variaçao expressiva, enquanto que os alfa-galactosídeos apresentaram decréscimo de até 80 por cento com os processos combinados de maltagem e extrusao.

Humans , Male , Female , Food Handling/methods , Soybeans/chemistry , alpha-Galactosidase/analysis , Flour , Nutritive Value , Phytic Acid/analysis , Seeds , Trypsin Inhibitors/analysis
Arch. latinoam. nutr ; 37(2): 342-50, jun. 1987. ilus, tab
Article in Spanish | LILACS | ID: lil-103790


Se determinaron los contenidos de hierro, calcio, zinc y ácido fítico de mezclas vegetales elaboradas a partir de trigo, maíz y soja. La utilización de soja en productos compuestos, en sustición de trigo y maíz, aporta una cantidad apreciable de hierro y calcio a las mezclas, en tanto que no modifica en forma significativa el contenido inicial d eácido fítido del trigo ni del máiz. Los procesos tecnológicos de descascarado e inactivación de enzimas denotan poca influencia sobre el contenido de minerales en soja, y el de extrusión en la cantidad de hierro soluble en mezclas. La incorporación de soja en mezclas vegetales disminuye considerablemente la disponibilidad levemente disminuiyendo la disponibilidad del hierro, respecto a las mezclas vegetales fortificadas sólo con dicho mineral

Calcium/analysis , Food Technology , Food, Fortified , In Vitro Techniques , Iron/analysis , Phytic Acid/analysis , Soybeans , Triticum , Zea mays