Avaliação das atividades citotóxica e genotóxica de Taninos de Mimosa arenosa (Willd.) Poir. (MIMOSACEAE)

Abstract

Natural products represent a rich source of biologically active compounds and are an example of molecular diversity, with recognized potential in the discovery and development of new drugs The genus Mimosa is distributed in various environments and various types of vegetation in tropical regions. In northeast Brazil can be found in the state of Bahia, Pernambuco and Paraíba. Many species of Mimosa are economically important, however, few biological studies of plants of this kind were carried out so far, with proven antibacterial and allelopathic activity. Therefore, the objective of this study was to evaluate the cytotoxic and genotoxic activities of the species M. arenosa (Willd.) Poir. tannins. The minimum inhibitory concentration (MIC) obtained for Pseudomonas aeruginosa ATCC 8027 and Pseudomonas aeruginosa ATCC 25619 was 1000μg, for Bacillus subtilis ATCC 0516 and Escherichia coli ATCC 2536 MIC was 500μg, as to the strains of Staphylococcus aureus ATCC 6538, Staphylococcus aureus ATCC 25925 and Escherichia coli ATCC 10536 the amount of tannin required to inhibit the growth of these bacteria was 250μg. The antibacterial activity exerted by Mimosa arenosa tannins against all strains tested was bacteriostatic. In the evaluation of cytotoxicity in any of the tested concentrations of tannins M. arenosa no caused significant hemolysis of red cells in any of the blood groups tested. However, the tannins were unable to protect the erythrocyte cells when exposed to hypotonic salt solutions. The tannins were not affected in any of the oxidant concentrations tested but they have reduced the oxidation of hemoglobin when exposed to an oxidizing agent. The tannins were not able to induce mutations but showed antimutagenic effect in strains of S. thyphimurium. Tannins did not induce structural cromossomal damage and/or numerical in erythrocytes of mouse.