Investigação dos efeitos antibacteriano, antioxidante, citotóxico e genotóxico do óleo essencial do caule de Croton tricolor Klotzsch ex Baill.

Abstract

The use of natural products by man goes back to the origins of the human species, which over the evolutionary process, was learning how to select plants for their food and for the relief of their ailments and diseases. Essential oils are complex organic constituents produced by aromatic plants as secondary metabolites, known for its medicinal properties. Croton tricolor Klotzsch ex Baill is a species belonging to Euphorbiaceae family, with antimicrobial and antioxidant properties. This study aimed to evaluate the antibacterial activity against Gram positive bacterial strains (Staphylococcus aureus) and Gram-negative (Escherichia coli), as well as antioxidant activity, cytotoxic and genotoxic of the essential oil of C. tricolor stem (Ct-OEc). The antibacterial activity was evaluated by determining the minimum inhibitory concentration (MIC) by the broth microdilution technique and characterization of the bactericidal effect by plating and spectrophotometry. The oxidant and antioxidant activities were determined in human blood type O erythrocytes in the absence and presence of phenylhydrazine. The in vitro cytotoxicity was determined by quantification of the hemolysis against human red cells of blood types A, B and O. The investigation of genotoxicity in vivo was performed using the micronucleus test in Swiss mice. The results indicate the presence of antimicrobial activity Ct-OEC front strains of S. aureus ATCC 25925 and E. coli ATCC 2536, E. coli ATCC 8539, E. coli 101 and E. coli 105 at a concentration of 1 mg. ml-1 (MIC). The Ct-OEc has no oxidizing effect at the concentrations tested and displays antioxidant effect at the concentration of 1000μg/mL. In evaluating the genotoxic potential by micronucleus test in mice, it was found that Ct-OEC not led to increased frequency of micronuclei in the peripheral blood of mice. Thus it was concluded that the essential oil of Croton tricolor has antibacterial activity, no effects on cell membrane, in low concentrations, without inducing oxidative, has antioxidant activity, without aneugenic and clastogenic effects.