Prospecção fitoquímica e avaliação das ações mutagênica, genotóxica e antioxidante de figueiras brasileiras - Ficus subg. Pharmacosycea (Miq.) Miq.

• Ano de defesa: 2012
• Autor(a) principal: Silva, Hugo Rody Vianna
• Orientador(a): Leite, João Paulo Viana
• Banca de defesa: Oliveira, Leandro Licursi de
• 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: Mutagenicidade; Genotoxidade; Etnofarmacologia
• Palavras-chave em Inglês: Mutagenicity; Genotoxicity; Ethnopharmacology
• Área do conhecimento CNPq: CNPQ::CIENCIAS BIOLOGICAS::BIOQUIMICA
• Link de acesso: http://locus.ufv.br/handle/123456789/2443

The genus Ficus, represented by plants popularly known as figs, makes up one of the largest genera of angiosperms with more than 800 species distributed in tropical and subtropical regions around the world. There is great interest in the study of nontimber forest product species of the genus Ficus, especially because there are several reports on the traditional use of these plants as food and medicine sources. Given the importance of investigating the chemical composition and toxicological effects of lant species used in folk medicine, the objective of this study was to explore phytochemical extracts of leaves from four species of Ficus, as well as quantify to total polyphenols by the Folin-Ciocalteau method and evaluate of antioxidant activity using the β-carotene/linoleic acid system and method for capture of the free radical DPPH. For three of these extracts the mutagenic activities were evaluated by the reverse mutation test with Salmonella typhimurium, with and without metabolization; and genotoxic potential on plasmid DNA pUC18. Phytochemical prospection revealed secondary metabolites of the classes of tannins and flavonoids in extracts of the species F. pulchella, F. adhatodifolia, F. nevesiae and F. obtusiuscula. The extracts of F. pulchella and F. obtusiuscula showed higher levels of total polyphenols (117 and 127.26 mg TAE/g, respectively) and higher antioxidant potential assessed by the two methods used in this study. In the test with Salmonella typhimurium, the extract of F. pulchella was considered mutagenic for the strains TA98 (S9+ and S9-), TA100 (S9-) and TA102 (S9+). The extracts of F. adhatodifolia and F. obtusiuscula were considered mutagenic only for the strain TA102 (S9+). These last two extracts also showed genotoxic effect in a dose of 1 mg, indicated by the decrease in superhelical conformation of the plasmid DNA. Genotoxic effects of the F. pulchella extract could not be assessed since no DNA bands were observed on the agarose gel, attributed to the degradation of plasmid DNA by polyphenols. Results obtained in this study indicate the presence of high levels of phenolic compounds in the four Ficus species evaluated, indicating the possible attribution of antioxidant action to these compounds present in hydrophilic extracts; was observed by the method of β-carotene/linoleic acid correlation between polyphenol content and antioxidant activity. The detection of mutagenic action for the species F. pulchella, F. adhatodifolia and F. obtusiuscula, and genotoxic effects for these last two in the doses evaluated indicates that these species should be used with care in folk medicine, because they act directly on DNA. However, further studies should be conducted with these Ficus species to confirm its potential toxicity.