Mophomutagenesis risk and larvicide activity of the essential oil of Christmas berry, Schinus terebinthifolia Raddi against Aedes aegypti (L.)

Abstract

Dengue is now the main re-emerging and seasonal disease in the world. In the absence of an effective preventive vaccine, of etiologic treatment and of chemoprophylaxis, the only vulnerable link for reducing dengue transmission is the mosquito Aedes aegypti, its main vector. Therefore, this study aimed to evaluate the larvicidal effect of the Chistmas berry (Schinus terebinthifolius) essential on larvae of this mosquito, and determining the median lethal concentration – LC50. The essential oil was extracted by hydrodistillation in a modified Clevenger apparatus, where once obtained, the essential oil was purified and dispersed in a 0.4% solution of Tween 20 as a disperser system. From that solution, 10 mL were assigned to each test tube in which each tube received 10 larvae, and eight replicates prepared with essential oil dilutions from 0.1% to 1.0% concentration of essential oil. in this study the mutagenic potential that the essential oil can manifest in microorganisms, for it has made dilutions of essential oil in nutrient broth was also evaluated, taking Salmonella choleraesuis ATCC 10,708 as biological model. That microorganism was grown in the presence of the subminimum inhibitory essential oil concentration, meanwhile, were sown in the same culture medium specific for growth and evaluated the morphology of the colony of bacteria to investigate possible changes, and the induced mutation characterized by the the development of lysine decarboxilation Bpositive reaction. The larvae examinations were made every 24 hours, until 72 hours in total death of the larvae, and growth of bacteria in specific media, but failed to identify changes that implied evidence morphomutagenicity in colonies of Salmonella and in relation to biological assay with the larvae could not make the determination of LC50 in this study, but the procedures in support of that determination are in process.