Speakers - Rose M. Carlos


Type of the Presentation: (Short lecture)




Eldevan Silvaa, Maria F. G. F. Silvaa, João B. Fernandesa, Odair C. Buenob, Maria A. B. F. Vitalc, Helena C. S. Assisc, Rose M. Carlosa*


a Departamento de Química, Universidade Federal de São Carlos, CP 676, 13565-905, São Carlos, SP, Brazil

bInstituto de Biociências, Universidade Estadual Paulista, 13506-900, Rio Claro, SP, Brazil

cDepartamento de Farmacologia, Universidade Federal do Paraná, Setor de Ciências Biológicas, 81531-980, Curitiba, PR, Brazil

Correspondence: *rosem@ufscar.br, +55-16-33518780, FAX +55-16-3351-8350


Pesticides offer a simple, cost-effective solution to ensure food supplies for a growing world population. However, their environmental performance needs improvement if pesticides are to continue contributing importantly. This study explores the insecticide potential of a Mg-containing isovanillic-acid compound against leaf-cutting ant (Atta sexdens rubropilosa) and its symbiotic fungus (Leucoagaricus gongylophorus), evaluating its toxicity to Zebrafish and Wistar male rats. The easy-to-prepare, stable in aqueous solution, resistant to sunlight irradiation Mg-complex [Mg(phen)(iso)(OH)(H2O)] has been synthesized and characterized by EA (C,H,N), FTIR, NMR, and DFT calculations. The compound-containing bait showed delayed action mode at 2 mgg-1 (100% kill, 6th day, S50=2b) and suppressed fungus development and growth. No mortality or visual alterations were observed on Zebrafish exposed to complex at concentrations up to 2.0 mgL-1 after 96 h. No adverse effects were found for Wistar male rat exposure to 3.0 mg Kg-1 day-1 dose for 21 days. The complex does not affect the activity of brain-acethylcholinesterase, digestive-tract-catalase and glutathione-S-transferase enzymes of both fish and rat. Conversely, performance of superoxide dismutase activity increases in the presence of complex, with resulting enhanced capacity of both animal species for superoxide radical enzymatic scavenging. The results indicate an interesting profile of biologic activity with strong insecticide activity against both the leaf-cutting ant Atta sexdens rubropilosa and its symbiotic fungus Leucoagaricus gongylophorus. The high stability in solid state and - aqueous medium, in the dark and when exposed to sun light and, the low lipophilicity suggest that the complex will have low persistence in aquatic medium and will probably be degraded by microbial process. These results, together with the lack of toxicity for Zebrafish and Wistar male rat, emphasize the potential of complex as an environmentally friendly insecticide.


1. Oliveira, R. M. M., de Souza Daniel, J. F., de Aguiar, I., das Graças Fernandes Silva, M. F., Batista Fernandes, J., & Carlos, R. M. (2013). Structural effects on the hesperidin properties obtained by chelation to magnesium complexes. Journal of Inorganic Biochemistry, 129, 35–4.