Environmentally Safe Photodynamic Control of <i>Aedes aegypti</i> Using Sunlight-Activated Synthetic Curcumin: Photodegradation, Aquatic Ecotoxicity, and Field Trial
Alessandra R. Lima,
Cicera M. Silva,
Lucas M. da Silva,
Amilcar Machulek,
Antônio P. de Souza,
Kleber T. de Oliveira,
Larissa M. Souza,
Natalia M. Inada,
Vanderlei S. Bagnato,
Samuel L. Oliveira,
Anderson R. L. Caires
Affiliations
Alessandra R. Lima
Institute of Physics, Federal University of Mato Grosso do Sul, Campo Grande 79070-900, Brazil
Cicera M. Silva
Institute of Physics, Federal University of Mato Grosso do Sul, Campo Grande 79070-900, Brazil
Lucas M. da Silva
Institute of Chemistry, Federal University of Mato Grosso do Sul, Campo Grande 79070-900, Brazil
Amilcar Machulek
Institute of Chemistry, Federal University of Mato Grosso do Sul, Campo Grande 79070-900, Brazil
Antônio P. de Souza
Institute of Biosciences, Federal University of Mato Grosso do Sul, Campo Grande 79070-900, Brazil
Kleber T. de Oliveira
Department of Chemistry, Federal University of São Carlos, São Carlos 13565-905, Brazil
Larissa M. Souza
São Carlos Institute of Physics, University of São Paulo, São Carlos 13566-590, Brazil
Natalia M. Inada
São Carlos Institute of Physics, University of São Paulo, São Carlos 13566-590, Brazil
Vanderlei S. Bagnato
São Carlos Institute of Physics, University of São Paulo, São Carlos 13566-590, Brazil
Samuel L. Oliveira
Institute of Physics, Federal University of Mato Grosso do Sul, Campo Grande 79070-900, Brazil
Anderson R. L. Caires
Institute of Physics, Federal University of Mato Grosso do Sul, Campo Grande 79070-900, Brazil
This study reports curcumin as an efficient photolarvicide against Aedes aegypti larvae under natural light illumination. Larval mortality and pupal formation were monitored daily for 21 days under simulated field conditions. In a sucrose-containing formulation, a lethal time 50 (LT50) of 3 days was found using curcumin at 4.6 mg L−1. This formulation promoted no larval toxicity in the absence of illumination, and sucrose alone did not induce larval phototoxicity. The photodegradation byproducts (intermediates) of curcumin were determined and the photodegradation mechanisms proposed. Intermediates with m/z 194, 278, and 370 were found and characterized using LC-MS. The ecotoxicity of the byproducts on non-target organisms (Daphnia, fish, and green algae) indicates that the intermediates do not exhibit any destructive potential for aquatic organisms. The results of photodegradation and ecotoxicity suggest that curcumin is environmentally safe for non-target organisms and, therefore, can be considered for population control of Ae. aegypti.
