Abordagem etológica na busca de drogas vegetais com potencial ação antioxidante, antibacteriana, antimutagênica e antigenotóxica

• Autor(a) principal: Gontijo, Douglas da Costa
• Data de Publicação: 2012
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/2450
• topic: Drogas vegetais; Ação antioxidante; Abordagem etológica; Herbal drugs; Antioxidant; Ethological approach; CNPQ::CIENCIAS BIOLOGICAS::FARMACOLOGIA::ETNOFARMACOLOGIA

The scientific research of biological activity of plant extracts has been an important strategy for the discovery of natural products with wide application in Research, Development & Innovation (RD&I). In a country with rich biodiversity such as Brazil, this statement assumes even greater value. The use of strategies for access the biodiversity is important for selecting plants for exploration of new drugs. In this sense, the ethological approach monitoring the diet of primates in the forest has been quite effective, since these mammals make use of a wide range of species that often are not part of everyday and scientific. Applying this ethological approach, the present study aimed to assess the potential antioxidant in vitro and antimicrobial, as well as preliminary phytochemical analysis and phenolic content of seven freeze-dried aqueous extracts of leaves of plants used in the diet of primate Brachyteles hypoxanthus Kuhl (muriqui-do-norte), as follows: Alchornea glandulosa Poepp. & Endl. (Euphorbiaceae), Miconia latecrenata (DC.) Naudin (Melastomataceae), Ocotea odorifera (Vell.) Rohwer (Lauraceae), Psychotria suterella Müll. Arg. (Rubiaceae), Psychotria vellosiana Benth. (Rubiaceae), Rudgea jasminoides (Cham.) Müll. Arg. (Rubiaceae) and Solanum swartzianum Roem. & Schult (Solanaceae). Among these three species, Alchornea glandulosa, Miconia latecrenata and Ocotea odorifera were evaluated for the potential antimutagenic and antigentoxic, which presented higher antioxidant activity. The phytochemical prospection was assessed by TLC and the phenolic compound was evaluated using the Folin-Ciocalteu reagent. The antioxidant activity was evaluated by testing the free radical DPPH, co-oxidation of β-carotene/linoleic acid and lipid peroxidation of liposome. It was used two strains of Gram-positive bacteria Staphylococcus aureus 3993 and Staphylococcus aureus 4125, as well as Gram-negative bacteria Escherichia coli 24 to assess the antimicrobial activity. For antimutagenic tests the strains used were TA97, TA98, TA100 and TA102 of Salmonella typhimurium/micrssome with and without S9 metabolic activation, being carried out the co-incubating method of the extracts with different mutagenic patterns for the respective strains. Cytotoxicity test with the strain TA100 without S9 activation was performed in order to determine the dose of extract used in the antimutagenicity tests. Finally, the antigenotoxic test was carried out using the plasmid pUC18 co-incubated with genotoxic pattern and the same doses of the extracts tested for antimutagenicity. Thus, it was observe aqueous extracts of M. latecrenata, A. glandulosa and O. odorifera showed higher phenolic content. The analysis of antioxidant activity in three different tests showed high antioxidant potential of the samples, especially for the extracts of M. latecrenata, A. glandulosa, O. odorifera and Solanum swartzianum. The results showed strong antimicrobial potencial to the extracts of M. latecrenata, A. glandulosa and O. odorifera, whereas the extract of M. latecrenata extract was the only one active against Gram-negative bacteria Escherichia coli 24. Considering the tests of cytotoxicity against strain TA100 of Salmonella typhimurium/micrssome without S9 metabolism, the extract of M. latecrenata showed higher cytotoxic activity, followed by the extracts of A. glandulosa and O. odorifera. The highest antimutagenic activity was observed for the extract of M. latecrenata followed by the extracts of A. glandulosa and O. odorifera, especially against the strain TA102. It was also observed increased antimutagenic activity for the most of the strains tested after the metabolization of the extracts. It was not observed antigenotoxic action for any of the extracts tested. Therefore, in the present study was possible to select three extracts with potential antimutagenic and bactericidal activity against the strains tested.