Navegando por Assunto "Fedegoso"

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Acesso aberto (Open Access)
Aleloquímico produzido pela gramínea forrageira Brachiaria humidicola
(2005-03) SOUZA FILHO, Antonio Pedro da Silva; PEREIRA, Angela Albertina Gaspar; BAYMA, Joaquim de Carvalho
The traditional methods of weed control in cultivated pasture do not meet society's present and future needs of protecting natural resources and life quality. An alternative to this problem could be the use of secondary metabolites produced by plants. These products present few risks to the environment and meet society interests. Therefore, this research was carried out to isolate, identify and characterize the allelopathic activity of chemical compounds produced by the forage grass Brachiaria humidicola. The allelopathic effects of the extracts, fractions and compound were tested on seed germination and root elongation of the weeds Mimosa pudica, Senna obtusifolia and Senna occidentalis. Germination bioassays were developed under 25 ºC and a photoperiod of 12 hours. For root elongation, the bioassay conditions were 25 ºC and photoperiod of 24 hours. Hydromethanolic extract was used as a source for isolating and identifying p-coumaric acid. The allelopathic effects were positively related to p-coumaric acid concentration, weed species and the evaluated parameter. Comparatively, S. occidentalis and M. pudica showed the greatest sensitivity to the allelopathic effects. For S. obtusifolia no allelopathic effects promoted by p-coumaric acid on seed germination or on root elongation could be detected under the concentration of 1.0 and 8.0 mg L-1. Root elongation was more sensitive to p-coumaric acid allelophatic effects than seed germination.
Acesso aberto (Open Access)
Estudos de pré-formulação e formulação de Heliotropium indicum (L.) DC (Boraginaceae)
(Universidade Federal do Pará, 2010-01-14) COSTA, Russany Silva da; SILVA JÚNIOR, José Otávio Carréra; http://lattes.cnpq.br/4437885351749994
Heliotropium indicum L. (Boraginaceae) is a shrub, reaches up to 70 cm high. It is known as “fedegoso” in the north and northeast of Brazil. Because of the biological potential of this species, this work aims to determine the quality parameters of the vegetable drug to the final product and evaluate the antimicrobial activity of the leaves of H. indicum L. The purpose of obtaining a phytotherapic formulation semisolid, we used the parameters of quality control physical, chemical and physicalchemical described in the Brazilian Pharmacopoeia and others literature. The vegetable drug was classified as coarse powder, showed values of loss on drying and total ash of 12.88% and 17.14%, respectively. The thermogravimetric analysis of the powder and the extract showed that both had good physical stability up to 180 °C. The spectra in the region IR showed an increase in the intensity of the absorption bands of the extract, which may relates to the extraction of chemical constituents of the cellular matrix. The prospecting chemical extract confirmed the presence of classes of secondary metabolites already reported in literature. The chloroform fraction suggests the presence of alkaloids by precipitation test with Dragendorff reagent. The TLC and HPLC showed a possible presence of the same substance in the alkaloidal and hexane fractions. The crude extract inhibited the growth of Staphylococcus aureus with halos of 12.5 mm ± 0.707 and 10.5 ± 0.707 mm for concentrations of 500 and 250 mg / mL, respectively. The physical mixtures of the extract with adjuvant pharmaceutical used to develop the phytotherapic formulation showed no physical incompatibility and no significant changes in the absorption profile of the compounds analyzed. The phytotherapic formulation semi-solid has a good stability after the preparation, after the submission of the gel by centripetal force and after the action of heat stress.