Obtenção e padronização de extrato seco de Mikania laevigata (guaco)

• Ano de defesa: 2011
• Autor(a) principal: PINTO, Mariana Viana
• Orientador(a): BARA, Maria Teresa Freitas
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Goiás
• Programa de Pós-Graduação: Mestrado em Ciências Farmacêuticas
• Departamento: Ciências da Saúde - Farmácia
• País: BR
• Palavras-chave em Português: Guaco. Cumarina. Fitoterápico. Controle de qualidade. Plantas medicinais. Spray drying.
• Palavras-chave em Inglês: Mikania laevigata; Coumarin; Phytomedicines; Quality control; Medicinal plants; Spray drying
• Área do conhecimento CNPq: CNPQ::CIENCIAS DA SAUDE::FARMACIA
• Link de acesso: http://repositorio.bc.ufg.br/tede/handle/tde/2105

Mikania laevigata Sch.Bip. ex Baker., popularly known as guaco, is a Brazilian medicinal plant belonging to Asteraceae family and widely used in medicine to treat coughs and respiratory disorders. It presents bronchodilator and antiulcer activities among others. Coumarins, terpenes and organic acids are the main chemical constituents of this specie. In the literature no studies were found concerning the production of standardized dried extracts from this plant specie, therefore the aim of this study was the obtaining and the characterization of standardized dry extract of this plant specie. M. laevigata leaves were collected, dried and crushed, resulting in the plant drug. The hydroalcoholic extract was obtained by percolation of the drug plant and the extraction liquid used was ethanol 80% (v/v). After drying experiments were carried out in order to investigate the influences of the extract feed rate and the drying adjuvant ratio in the characteristics of the dried extracts obtained.-coumaric acid and coumarin were used as chemical markers and were quantified by High Performance Liquid Chromatography (HPLC) in all stages of the process. An analytical method was validated following the criteria proposed by the Agência Nacional de Vigilância Sanitária (ANVISA), proving to be selective, linear, precise, accurate, sensitive and robust. In the characterization of plant drug the volatile content obtained was 9.00 ± 1.75%, the coumarin content was 0.72 ± 0.02% and the acid -coumaric content was 0.13 ± 0.005%. The average particle size was 444.823 m and swelling index was 3.2 in ethanol 80%, 4.27 in ethanol 50% and 10.13 in water. The hydroalcoholic extract presented a density of 0.9256 ± 0.0006 g / mL, total solids content of 5.18 ± 0.21%, pH 6.1 ± 0.00, alcohol content of 56% and viscosity of 5.57 mPas. The drying yields ranged from 11.35 to 54.11%, and all dried products presented volatiles content and water activity below 5% and 0.5, respectively. The selected condition to be used to obtain standardized dried extracts of M. laevigata was that performed with a smaller proportion of colloidal silicon dioxide (15%) and increased extract feed rate (6mL/min), in which levels were obtained coumarin and -coumaric acid content of 1.83 ± 0.004% and 0.80 ± 0.012%, respectively. The dry extract obtained in these conditions showed spherical particles and their antiulcer activity in the model of indomethacin induced ulcers was demonstrated, suggesting a gastroprotective effect of this extract. Comparison of powder, hydroalcoholic and dry extract chromatographic (TLC and HPLC) show that the hydroalcoholic extraction was suitable for the extraction of coumarin and -coumaric acid and the drying process did not cause changes in the chemical profile of the extract in relation to these substances. Thus, the production of dried extracts by spray drying from the leaves of M. laevigata can be an interesting and promising alternative for obtaining such an intermediate product.