title: Acaricidal and repellent activity of terpenoids from seaweeds Collected in Pernambuco, Brazil.
abstract: n-Hexane and dichloromethane extracts obtained from Laurencia dentroidea (Rhodophyta) and Canistrocarpus cervicornis (Phaeophyta) were investigated for their acaricidal and repellent properties against Tetranychus urticae under laboratory conditions. The two extracts displayed moderate toxicity and good repellent proprieties, and were significantly more toxic (36-fold) than the positive control (eugenol), whereas eugenol was tenfold more repellent than either seaweed extract. The sesquiterpenoid elatol (1) was isolated from L. dentroidea and the diterpenoid seco-dolastane (4R,9S,14S)-4alpha-acetoxy-9beta, 14alpha-dihydroxydolast-1(15),7-diene (2) from C. cervicornis, the chemical structures of which were characterized by NMR spectroscopic data (1H and 13C) and by comparison with literature data. These compounds exhibited moderate toxicity, but a high degree of repellent activity against T. urticae. The findings suggest that marine natural products, specifically terpenes, can be employed for the development of new pesticides and become prototype agrochemical agents.
authors.affiliation: Programa de Pós-graduação em Entomologia Agricola, Departamento de Agronomia, Universidade Federal Rural de Pernambuco, Rua Dom Manoel de Medeiros, Sn, 52.171-900, Recife, PE, Brazil.
authors.forename: Flávia Souza
authors.initials: FS
authors.lastname: Born
authors.forename: Everson Miguel
authors.initials: EM
authors.lastname: Bianco
authors.forename: Claudio Augusto Gomes
authors.initials: CA
authors.lastname: da Camara
mesh_terms: D056810:Acaricides / Q000032:analysis*; D000818:Animals; D001938:Brazil; D012624:Seaweed / Q000737:chemistry*; D013141:Spiro Compounds / Q000302:isolation & purification; D013729:Terpenes / Q000737:chemistry*; D040102:Tetranychidae
chemical_list: D056810:Acaricides; D013141:Spiro Compounds; D013729:Terpenes; C485576:elatol