Prospecção fitoquímica e avaliação de mutagenicidade in vitro de três espécies vegetais: Strychnos pseudoquina A. St.-Hil., Coutarea hexandra (Jacq.) K. Schum e Bathysa cuspidata (A.St.-Hil.) Hook

• Ano de defesa: 2008
• Autor(a) principal: Nunes, Líria Granato
• Orientador(a): Leite, João Paulo Viana
• Banca de defesa: Barros, Ana Maria Dantas , Ribon, Andréa de Oliveira Barros
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Mestrado em Bioquímica Agrícola
• Departamento: Bioquímica e Biologia molecular de plantas; Bioquímica e Biologia molecular animal
• País: BR
• Palavras-chave em Português: Metabolismo secundário; Plantas medicinais; Mutagenicidade; Fitoquímica
• Palavras-chave em Inglês: Secondary metabolites; Medicinal plants; Mutagenicity; Phytochemistry
• Área do conhecimento CNPq: CNPQ::CIENCIAS BIOLOGICAS::FARMACOLOGIA::ETNOFARMACOLOGIA
• Link de acesso: http://locus.ufv.br/handle/123456789/2401

Brazil has the most diversified flora in the world concerning terrestrial plants, with about 45,000 species of superior plants, which correspond to almost 22% of all known vegetable species of the planet. In that great patrimony is worth emphasizing the importance of the chemical diversity of the biosynthetic secondary metabolites of these plants, which have recently arisen great interest of the pharmaceutical industry hoping to discover life-saving property drugs as well as new raw materials for the industry in general. In that scenery, the phytotherapy has revived as a therapeutic option well accepted and accessible in different countries, including Brazil. However, the vast majority of Brazilian medicinal plants heritage along with its usage, chemical, toxicological, pharmacological properties lack of appropriate assessment. It is important to fully investigate them all in order to prevent any possible mutagenic and/or other risks related to it. In that context, the present work aims at the study of barks and leaves of three native species of the popularly known as quina which is used in traditional medicine: Strychnos pseudoquina A. St.-Hil., Loganiaceae family; Coutarea hexandra (Jacq.) K. Schum and Bathysa cuspidata (A.St.-Hil.) Hook., both of the Rubiaceae family. That study carried out phytochemistry prospection through Thin Layer Chromatography (TLC) of gel silica and through High- performance Liquid Chromatography (HPLC), as well as the quantitative analysis of groups of potentially active secondary metabolites, so as to compare the chemical composition among the species, and also aid in the identification of the respective vegetable drugs. Another appraised aspect was the mutagenic action of the extracts using Ames Test assay of reverse genic mutation in Salmonella typhimurium. Once the investigated vegetable species belong to botanical genus that are bearers of active alkaloids, the presence of the natural occurring products quinine and strychnine, obtained from commercial samples, was investigated in the extracts, being appraised also as to the mutagenic potential. The results obtained by the phytochemistry prospection showed certain similarity among the groups of secondary metabolites found in the appraised species. Among barks and leaves of the three vegetable species differences were detected in the chemical composition. By the quantification of total polyphenolics, proanthocyanidins and flavonoids variation can be verified in the chemical content of them in the different species. The species B. cuspidata and C. hexandra did not present mutagenic potential in leaves and barks when confronted with TA 100 and TA 98 strains. For the species S. pseudoquina, barks of the stem did not show mutagenic action while the extracts of leaves presented mutagenic potential for TA100 and TA98 strains in the used doses. There was no evidence of the presence of the alkaloids quinine and strychnine in the extracts through TLC. Standards of these alkaloids did not present mutagenic potential but cytotoxicity in high doses. Due to the fact that the popular use of these three species the bark constitutes the most employed part, the mutagenicity absence demonstrated by the Ames test for that pharmacogene is a subsidy for the establishment of the safety of these vegetable drugs. The use of leaves of S. pseudoquina requests caution and should be banned since further studies will be necessary to evaluate that mutagenic potential.