Marilza S Costa1, Antônio Eg Santana2, Leandro L Oliveira3, José C Zanuncio1, José E Serrão4. 1. Department of Entomology, Federal University of Viçosa, Viçosa, Minas Gerais, Brazil. 2. Institute of Chemistry and Biotechnology, Federal University of Alagoas, Maceió, Alagoas, Brazil. 3. Department of General Biology, Federal University of Viçosa, Viçosa, Minas Gerais, Brazil. 4. Laboratory of Ultrastructural Cell, Department of General Biology, Federal University of Viçosa, Viçosa, Minas Gerais, Brazil.
Abstract
BACKGROUND: The mosquito Aedes aegypti transmits a virus that causes diverse human diseases, and control of the vector is an important strategy to avoid disease propagation. Plants in the family Annonaceae are recognised as sources of molecules with uses in the medical and agriculture fields. Molecules of secondary metabolites of Annonaceae plants exhibit insecticidal potential against insect pests and vectors, especially acetogenins, showing high toxicity at low doses, which has encouraged research into producing new insecticide molecules. Herein, we identify an acetogenin from Annona mucosa seeds (chemical analysis) and provide the results of toxicity tests against larvae of A. aegypti (target insect) and its predators Culex bigoti and Toxorhynchites theobaldi (non-target insects) and cytotoxicity to human leukocytes. RESULTS: We identified squamocin (C37 H66 O7 ), a fatty acid with a bis-tetrahydrofuran ring. In A. aegypti, this compound caused behavioural disturbance before larval death and high mortality at low concentrations (LC50 = 0.01 µg mL-1 and LC90 = 0.11 µg mL-1 ). However, in predators and human leukocytes, squamocin showed no toxicity effect, indicating the selectivity of this molecule for non-target organisms. CONCLUSION: We identified squamocin from A. mucosa seeds, which exhibited lethal action against A. aegypti and showed selectivity for non-target insects and low cytotoxicity to human cells.
BACKGROUND: The mosquito Aedes aegypti transmits a virus that causes diverse human diseases, and control of the vector is an important strategy to avoid disease propagation. Plants in the family Annonaceae are recognised as sources of molecules with uses in the medical and agriculture fields. Molecules of secondary metabolites of Annonaceae plants exhibit insecticidal potential against insect pests and vectors, especially acetogenins, showing high toxicity at low doses, which has encouraged research into producing new insecticide molecules. Herein, we identify an acetogenin from Annona mucosa seeds (chemical analysis) and provide the results of toxicity tests against larvae of A. aegypti (target insect) and its predators Culex bigoti and Toxorhynchites theobaldi (non-target insects) and cytotoxicity to human leukocytes. RESULTS: We identified squamocin (C37 H66 O7 ), a fatty acid with a bis-tetrahydrofuran ring. In A. aegypti, this compound caused behavioural disturbance before larval death and high mortality at low concentrations (LC50 = 0.01 µg mL-1 and LC90 = 0.11 µg mL-1 ). However, in predators and human leukocytes, squamocin showed no toxicity effect, indicating the selectivity of this molecule for non-target organisms. CONCLUSION: We identified squamocin from A. mucosa seeds, which exhibited lethal action against A. aegypti and showed selectivity for non-target insects and low cytotoxicity to human cells.