title: Insecticidal activity of Leptodactylus knudseni and Phyllomedusa vaillantii crude skin secretions against the mosquitoes Anopheles darlingi and Aedes aegypti.
abstract: BACKGROUND
  Mosquitoes are important vectors of several diseases, including malaria and dengue, and control measures are mostly performed using chemical insecticides. Unfortunately, mosquito resistance to commonly applied insecticides is widespread. Therefore, a prospection for new molecules with insecticidal activity based on Amazon biodiversity using the anurans Leptodactylus knudseni and Phyllomedusa vaillantii was performed against the mosquito species Anopheles darlingi and Aedes aegypti.
  
  
  METHODS
  The granular secretion from anuran skin was obtained by manual stimulation, and lethal concentrations (LCs) for larvicidal and adulticidal tests were calculated using concentrations from 1-100 ppm. The skin secretions from the anuran species tested caused significant mortality within the first 24 hours on adults and larvae, but differed within the mosquito species.
  
  
  RESULTS
  The skin secretions from the anuran species tested caused significant mortality within the first 24 hours on adults and larvae, but differed within the mosquito species. The calculated LC50 of L. knudseni skin secretions against An. darlingi was 0.15 and 0.2 ppm for adults and larvae, respectively, but much higher for Ae. aegypti, i.e., 19 and 38 ppm, respectively. Interestingly, the calculated LCs50 of P. vaillantii against both mosquito species in adults were similar, 1.8 and 2.1 ppm, respectively, but the LC50 for An. darlingi larvae was much lower (0.4 ppm) than for Ae aegypti (2.1 ppm).
  
  
  CONCLUSIONS
  The present experiments indicate that skin secretions from L. knudseni and P. vaillantii contain bioactive molecules with potent insecticide activity. The isolation and characterization of skin secretions components will provide new insights for potential insecticidal molecules.
authors.affiliation: Laboratory of Insect Bioecology, Department of Biology, Federal University of Rondônia (UNIR), Porto Velho, Rondônia State, Brazil ; Oswaldo Cruz Foundation - Rondônia (Fiocruz - Rondônia), Porto Velho, Rondônia State, Brazil.
authors.forename: Frances Tt
authors.initials: FT
authors.lastname: Trindade
authors.affiliation: Center for the Study of Biomolecules Applicable to Health, Oswaldo Cruz Foundation - Rondônia, and Department of Medicine, Federal University of Rondônia (UNIR), Porto Velho, Rondônia State, Brazil.
authors.forename: Angela A
authors.initials: AA
authors.lastname: Soares
authors.affiliation: Center for the Study of Biomolecules Applicable to Health, Oswaldo Cruz Foundation - Rondônia, and Department of Medicine, Federal University of Rondônia (UNIR), Porto Velho, Rondônia State, Brazil.
authors.forename: Andréa A
authors.initials: AA
authors.lastname: de Moura
authors.affiliation: Center for the Study of Biomolecules Applicable to Health, Oswaldo Cruz Foundation - Rondônia, and Department of Medicine, Federal University of Rondônia (UNIR), Porto Velho, Rondônia State, Brazil.
authors.forename: Tiago B
authors.initials: TB
authors.lastname: Rego
authors.affiliation: Center for the Study of Biomolecules Applicable to Health, Oswaldo Cruz Foundation - Rondônia, and Department of Medicine, Federal University of Rondônia (UNIR), Porto Velho, Rondônia State, Brazil.
authors.forename: Andreimar M
authors.initials: AM
authors.lastname: Soares
authors.affiliation: Oswaldo Cruz Foundation - Rondônia (Fiocruz - Rondônia), Porto Velho, Rondônia State, Brazil ; Center for the Study of Biomolecules Applicable to Health, Oswaldo Cruz Foundation - Rondônia, and Department of Medicine, Federal University of Rondônia (UNIR), Porto Velho, Rondônia State, Brazil.
authors.forename: Rodrigo G
authors.initials: RG
authors.lastname: Stábeli
authors.affiliation: Oswaldo Cruz Foundation - Rondônia (Fiocruz - Rondônia), Porto Velho, Rondônia State, Brazil ; Center for the Study of Biomolecules Applicable to Health, Oswaldo Cruz Foundation - Rondônia, and Department of Medicine, Federal University of Rondônia (UNIR), Porto Velho, Rondônia State, Brazil.
authors.forename: Leonardo A
authors.initials: LA
authors.lastname: Calderon
authors.affiliation: Laboratory of Insect Bioecology, Department of Biology, Federal University of Rondônia (UNIR), Porto Velho, Rondônia State, Brazil ; Oswaldo Cruz Foundation - Rondônia (Fiocruz - Rondônia), Porto Velho, Rondônia State, Brazil.
authors.forename: Alexandre de Almeida
authors.initials: Ade A
authors.lastname: E Silva
keywords: Anuran amphibians; Dengue; Malaria; Vector control