Amino acid profile in cassava and its interspecific hybrid

Cassava roots have a low-protein content (0.7-2%). Amino acids such as lysine and methionine are also low, and some research reports have indicated the absence of methionine. The amino acid profiles of a common cassava cultivar and an interspecific hybrid, namely ICB 300, were determined using the computerized amino acid analyzer Hitachi L-8500. The interspecific hybrid has 10 times more lysine and 3 times more methionine than the common cassava cultivar: lysine content was 0.010 g per 100 g in the common cassava cultivar while it reached 0.098 in the interspecific hybrid. Methionine in the common cassava cultivar was 0.014 g per 100 g whereas it reached 0.041 g per 100 g in the interspecific hybrid. Total amino acid content in the common cassava cultivar was 0.254 g per 100 g viz. a viz. 1.664 g per 100 g in the interspecific hybrid. The genetic variability of the profile and quantity of amino acids indicate the feasibility of selecting interspecific hybrids that are rich in both crude protein and amino acids. This is the first report of high true protein in cassava root.

Correlation between fertility and levels of protein, sugar and free amino acids in seminal plasma of Nelore bulls

Estimaram-se as correlações entre fertilidade e concentrações de proteínas, açúcares redutores e 17 tipos de aminoácidos livres do plasma seminal de 19 touros Nelore, adultos, doadores de sêmen de alta qualidade segundo as análises físicas e morfológicas. O escore de fertilidade foi estimado de acordo com a porcentagem de gestação das fêmeas cobertas em três estações de monta consecutivas, por inseminação artificial ou monta natural. Foi observada alta variabilidade na concentração das moléculas analisadas nas amostras. O coeficiente de correlação estimado entre concentrações de proteína e de açúcares redutores foi de 0,90. Individualmente, nenhum dos componentes quantificados apresentou correlação significativa com a fertilidade dos touros.

Maillard's reaction in parenteral solutions supplemented with arginine

Arginine, as a basic amino acid, can alter the pH of a parenteral solution and consequently to interfere in the stability of other amino acids. The objective of this study was to analyze the chemical stability of amino acids in solutions for parenteral nutrition with arginine supplementation. Amino acids concentrations were determined using an amino acid analyzer in intervals of 12, 36, 72 hours, 7 and 28 days. Storage temperatures were -20 degrees C, 5 degrees C and 25 degrees C. A decrease was observed (p < 0.05) in the concentrations of threonine, methionine, isoleucine, leucine, proline and lysine on the 28th day of study, in the solutions kept at 25 degrees C. The side chains of threonine, methionine, isoleucine, leucine, proline and lysine have hydrophobic groups, which renders them less soluble in water when compared to amino acids that have polar side chains. The degradation of lysine was significant in the sample of parenteral nutrition supplemented with arginine, possibly due to the fact that the solution's pH was between 7.5 and 7.6, therefore facilitating the Maillard reaction between lysine and glucose.

Behavioral and electroencephalographic analysis of seizures induced by intrahippocampal injection of granulitoxin, a neurotoxic peptide from the sea anemone Bunodosoma granulifera

In this study, the behavioral and electroencephalographic (EEG) analysis of seizures induced by the intrahippocampal injection in rats of granulitoxin, a neurotoxic peptide from the sea anemone Bunodosoma granulifera, was determined. The first alterations occurred during microinjection of granulitoxin (8 µg) into the dorsal hippocampus and consisted of seizure activity that began in the hippocampus and spread rapidly to the occipital cortex. This activity lasted 20-30 s, and during this period the rats presented immobility. During the first 40-50 min after its administration, three to four other similar short EEG seizure periods occurred and the rats presented the following behavioral alterations: akinesia, facial automatisms, head tremor, salivation, rearing, jumping, barrel-rolling, wet dog shakes and forelimb clonic movements. Within 40-50 min, the status epilepticus was established and lasted 8-12 h. These results are similar to those observed in the acute phase of the pilocarpine model of temporal lobe epilepsy and suggest that granulitoxin may be a useful tool not only to study the sodium channels, but also to develop a new experimental model of status epilepticus.

Efeitos farmacológicos da suplementaçao dietética com arginina em ratos com tumor sólido de walker 256 / Pharmacological effects of arginine supplementation in rats walker 256 solid tumor

Os efeitos da suplementaçao com arginina na dieta de portadores de cancer sao controversos. O objetivo deste trabalho é avaliar os efeitos da suplementacao dietética com arginina no crescimento tumoral, disseminaçao metastática, metabolismo de aminóacidos, alteraçoes hematológicas, tempo de sobrevida e peso corporal de ratos Wistar com tumor sólido de Walker 256. Foram administradas soluçoes por via gástrica, contendo arginina nas concentraçoes de 4 por cento, 6 por cento e dieta padrao (controle). A suplementacao com arginina inibiu a desseminaçao de células tumorais no modelo experimental, embora crescimento tumoral nao tenha sido afectado significantemente. O tempo de sobrevida dos animais com tumor sólido nao foi afetado de forma significativa. Foi observado disminuiçao significativa de peso corpóreo após a administraçao da arginina a 6 por cento (p<0.05). O metabolismo dos aminóacidos foi estimulado após ingestao de suplementos com arginina, evidenciado pelos aumentos significativos dos níveis sanguíneos de arginina, ornitina, citrulina, prolina e histidina quando comparados ao grupo controle (p<0.001). O grau de anemia no tumor sólido foi menos severo nos grupos que receberam suplementaçao com arginina, evidenciado através do hemograma (p<0.001) e da análise citológica. Os resultados sugerem que a suplementaçao dietética com arginina a 6 por cento apresentou algum efeito benéfico no tumor sólido de Walker 256 que ultrapassa o efeito nutricional

Partial sequence and toxic effects of granulitoxin, a neurotoxic peptide from the sea anemone Bunodosoma granulifera

A neurotoxic peptide, granulitoxin (GRX), was isolated from the sea anemone Bunodosoma granulifera. The N-terminal amino acid sequence of GRX is AKTGILDSDGPTVAGNSLSGT and its molecular mass is 4958 Da by electrospray mass spectrometry. This sequence presents a partial degree of homology with other toxins from sea anemones such as Bunodosoma caissarum, Anthopleura fuscoviridis and Anemonia sulcata. However, important differences were found: the first six amino acids of the sequence are different, Arg-14 was replaced by Ala and no cysteine residues were present in the partial sequence, while two cysteine residues were present in the first 21 amino acids of other toxins described above. Purified GRX injected ip (800 µg/kg) into mice produced severe neurotoxic effects such as circular movements, aggressive behavior, dyspnea, tonic-clonic convulsion and death. The 2-h LD50 of GRX was 400 ñ 83 µg/kg

Enterolobin induces rat paw oedema independently of PAF-acether

The potential participation of PAF-acether (PAF) on the paw oedema triggered by enterolobin was investigated. Intraplantar injections of enterolobin )5-20 µg/paw) yielded a dose response curve for edema which appeared after 30 min, peaked in the interval between 2-4 h and faded after 24h. The pre-treatment with BN 52021, but not with other PAF antagonists such as PCA 4248 or WEB 2086, significantly blocked enterolobin-induced oedema. To clarify better the discrepant results obtained with the PAF antagonists, desensitization to PAF was performed. The oedema triggered by enterolobin was not modified in paf desensitized animals. It was concluded that the paw inflammation induced by enterolobin does not require PAF mechanism.