RESUMO
Four new metabolites with carotane skeletons, trichocaranes A (1), B (2), C (3), and D (4), were isolated from Trichoderma virens and their structures established by the interpretation of NMR and mass spectroscopic data. The trichocaranes significantly inhibited the growth of etiolated wheat coleoptiles: 40% at 10(-4) M with 1 and 2 and 86% at 10(-3) M with 3.
Assuntos
Sesquiterpenos/farmacologia , Trichoderma/química , Triticum/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Triticum/crescimento & desenvolvimentoRESUMO
The structures of four new, naturally occurring bioactive spiroditerpenoids, (+)-breviones B, C, D, and E, potential allelopathic agents, have been determined from extracts of semisolid fermented Penicillium brevicompactum Dierckx. The structures display the novel breviane spiroditerpenoid skeleton. Structure elucidation was performed by chemical transformations and by homo- and heteronuclear 2D-NMR spectral data. On the basis of combined studies of the theoretical conformations and NOEDIFF data, their relative stereochemistry is proposed. A mixed biogenesis for this novel family of spiroditerpenoids is tendered. The levels of activity shown by breviones B, C, and E in the etiolated wheat coleoptiles bioassay, especially breviones E (100% inhibition) and C (80% inhibition) both at 10(-4) M, suggest them as lead compounds for new agrochemicals.
Assuntos
Diterpenos/isolamento & purificação , Penicillium/química , Reguladores de Crescimento de Plantas/isolamento & purificação , Compostos de Espiro/isolamento & purificação , Diterpenos/química , Fermentação , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Modelos Moleculares , Penicillium/metabolismo , Reguladores de Crescimento de Plantas/química , Reguladores de Crescimento de Plantas/farmacologia , Espectrofotometria Infravermelho , Compostos de Espiro/química , Compostos de Espiro/farmacologia , Estereoisomerismo , Triticum/efeitos dos fármacos , Triticum/crescimento & desenvolvimentoRESUMO
White grape seeds were subjected to sequential supercritical fluid extraction. By increasing the polarity of the supercritical fluid using methanol as a modifier of CO(2), it was possible to fractionate the extracted compounds. Two fractions were obtained; the first, which was obtained with pure CO(2), contained mainly fatty acids, aliphatic aldehydes, and sterols. The second fraction, obtained with methanol-modified CO(2), had phenolic compounds, mainly catechin, epicatechin, and gallic acid. The fractions were bioassayed. Antimicrobial activities were checked on human pathogens, and a high degree of activity was obtained with the lipophilic fraction. Agrochemical activities on phytopathogenic fungi and activities on the etiolated wheat coleoptile bioassay were also checked. The more polar fraction was active in the latter bioassay.
Assuntos
Rosales/química , Sementes/química , Bactérias/efeitos dos fármacos , Bioensaio , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Fungos/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia , Triticum/efeitos dos fármacosRESUMO
Serum vitamin A was determined before and 30-45 d after the administration of 60.6 mg (212 mumol) vitamin A to 544 Brazilian children residing in slum areas of Recife. The frequency-distribution curves were compared in a subgroup of children whose vitamin A status was assessed initially by the relative-dose-response (RDR) test. The curves of children with negative (adequate status) and positive (inadequate status) RDR tests were different. The difference disappeared after supplementation. The shape of the distribution curve after supplementation was close to normal with a mean, median, and 95% confidence interval of 1.78 +/- 0.49, 1.68, and 1.02-2.90 mumol/L, respectively. The postsupplementation curve derived from this underprivileged child population may serve as a reference for diagnostic, surveillance, and program-evaluation purposes.
Assuntos
Áreas de Pobreza , Vitamina A/sangue , Brasil , Pré-Escolar , Relação Dose-Resposta a Droga , Humanos , Valores de Referência , Vitamina A/administração & dosagemRESUMO
The effect of the addition of aflatoxin B1 was studied in 48 male, Sprague-Dawley rats weaned at 21 days of age. The animals of the experimental group received one of the following diets to which aflatoxin B1 was added (5 mg/kg ration), a protein-free diet, the regional basic diet of Northeast Brazil (RBD) containing 9.07% protein, and commercial casein diets (at 10 and 20%). The control groups were fed the same diets without aflatoxin B1. To detect possible body alterations, the body weight and food intake, as well as protein and aflatoxin B1 intakes were recorded. Significant alterations were detected in the experimental groups, especially in the protein-depleted animals, and in those fed the RBD and 10% commercial casein diets, when compared to their controls.
Assuntos
Aflatoxinas/farmacologia , Peso Corporal/efeitos dos fármacos , Alimentos Fortificados , Aflatoxina B1 , Aflatoxinas/administração & dosagem , Animais , Crescimento/efeitos dos fármacos , Masculino , Estado Nutricional , Ratos , Ratos EndogâmicosRESUMO
The actual knowledge about leprosy and its therapy determines it to be regarded and treated as any other disease. Leprosaria, dedicated to segregation and isolation the patient are not needed anymore. Accordingly, the only leprosarium that existed in Costa Rica, the "Sanatorio Nacional de las Mercedes", was closed on March 30, 1979. We are providing a historical account of the stages in the struggle against leprosy leading to the closure of the Sanatorio, as well as the main reasons supporting the inadequacy of having such an institution. We explain the meaning and advantages of the foster homes, where the last 30 remaining patients were replaced, thus facilitating the closure of the Sanatorio. Finally, three years later, we discuss the most significant results concerning the Hansen's disease control in Costa Rica.