Ação da pancreatina na obtenção de hidrolisados protéicos de soro de leite com elevado teor de oligopeptídeos / Action of pancreatin for obtaining whey protein hydrolysates with high oligopeptide contents

Vários hidrolisados enzimáticos de soro de leite foram preparados visando a elevação do teor de oligopeptídeos e a redução de custos para produção em larga escala. Para isso, empregou-se a pancreatina e alguns parâmetros hidrolíticos como o tempo de reação (5, 10 e 15h), a relação E:S (1:100, 2:100 e 4:100) e a concentração do substrato (10 e 15 por cento) foram testados. Os hidrolisados foram fracionados por cromatografia liquida de alta eficiência de exclusão molecular (SEHPLC) e, para a quantificação dos componentes das frações cromatográficas, empregou-se o método rápido da Área Corrigida da Fração. Para os parâmetros estudados, observou-se efeito benéfico sobre o perfil peptídico, sendo que o melhor resultado, associado, principalmente, ao maior teor de oligopeptídeos (49 por cento) e ao menor conteúdo de aminoácidos livres (22 por cento), foi obtido quando se empregou a concentração do substrato a 10 por cento, a relação E:S de 4:100 e o tempo de reação de 10h.

Several enzymatic hydrolysates of whey were prepared with the objective of increasing the oligopeptide content and reducing the cost of large scale production. Pancreatin was used and some hydrolytic parameters such as reaction time (5, 10 and 15h), enzyme:substrate ratio (E:S) (1:100, 2:100 and 4:100) and substrate concentration (10 and 15 percent) were tested. The hydrolysates were fractionated by size-exclusion-HPLC and the rapid corrected fraction area method was used for quantifying the chromatographic fractions. The beneficial effect on the peptide profile was observed in several cases, and it was mainly associated with higher oligopeptide (49 percent) and lower amino acid (22 percent) contents, which were obtained for a substrate concentration of 10 percent, E:S ratio of 4:100 and reaction time of 10h.

Prevention of bacterial translocation using glutamine: a new strategy of investigation.

OBJECTIVE: This study investigated the role of glutamine (Gln) on bacterial translocation in an intestinal obstruction model by using Escherichia coli labeled with technetium 99m (99mTc-E. coli). METHODS: Intestinal obstruction was performed by a single ligature of the terminal ileum in rats. Animals in the control group (group 1) were sham operated (not obstructed). Experimental group 2 had intestinal obstruction. Groups 1 and 2 were not treated with Gln. Groups 3 and 4 were treated with Gln for 7 d before surgery with 250 and 500 mg x kg(-1) x d(-1), respectively. A suspension containing 100 million colony-forming units/mL of (99m)Tc-E. coli was injected into the lumen of the ileum. Twenty-four hours after surgery, blood, mesenteric lymph nodes, livers, spleens, and lungs were collected for determination of radioactivity. The Mann-Whitney U test was performed for statistical analysis. P

Imobilização da pancreatina em carvão ativado e em alumina para o preparo de hidrolisados de soro de leite / Immobilization of pancreatin in activated carbon and in alumina for preparing whey hydrolysates

Tendo como objetivo a redução de custos do processo de fabricação de hidrolisados protéicos, estudou-se neste trabalho a imobilização da pancreatina, por adsorção, em carvão ativado e em alumina. Para isso, foram testadas diferentes condições de imobilização (30, 60 e 90min a 25°C, e 12h a 5°C). Para verificar a taxa de imobilização, determinou-se indiretamente a enzima não adsorvida nos suportes. Ao se utilizar o carvão ativado, não foi observada diferença significativa entre as condições testadas, tendo-se obtido 100% de imobilização enzimática. Para a alumina, a melhor condição foi a de 90min, na qual se obteve 37% de imobilização. A medida do grau de exposição da fenilalanina, pela espectrofotometria derivada segunda, foi empregada para a determinação da estabilidade operacional da enzima, tendo sido mostrado que a imobilização em carvão ativado e em alumina permitiu a reutilização da pancreatina por até 5 vezes e 2 vezes, respectivamente.

Immobilization of pancreatin in activated carbon and in alumina was studied for producing protein hydrolysates, in order to reduce the process costs. Different immobilization conditions were tested (30, 60 and 90min at 25°C, and 12h at 5°C). For estimating the immobilization rate the amount of the non-adsorbed enzyme on the supports was indirectly determined. When activated carbon was used, no significant difference was observed among the tested conditions, obtaining 100% of enzymatic immobilization. In case of alumina, the best condition showed to be the 90min treatment which produced 37% of immobilization. The evaluation of the degree of exposition of phenylalanine, by second derivative spectrophotometry, was used for the determination of the enzyme operational stability, and showed that the immobilization in activated carbon and in alumina allowed the reusability of the pancreatin for 5 times and 2 times, respectively.

Evoluçäo dos fenólicos totais e taninos condensados (Proantocianidinas) durante o desenvolvimento das sementes do feijäo (Phaseolus vulgaris L.) / Evolution of phenolic compounds and condensed tannins (Proanthocyanidins) during the development of bean seeds (Phaseolus vulgaris L.)

The evolution of phenolic compounds and tannins (proanthocyanidins) of bean seeds, Phaseolus vulgaris L., (cultivar aroana 80), from anthesis to maturity (10 to 45 days after anthesis), was investigated. During seed development, phenolic compounds and tannins contents increased by seed unit, until the 31st and 21st day after anthesis respectively, decreasing afterwards. The gradual decrease in catechin and the increase of its polymers (intermediate compounds), as well as the gradual increase in alpha-amylase inhibition capacity were indications that tannins polymerize during seed development