Relação entre a toxicidade de mono e sesquiterpenos identificados no óleo essencial de espécies dos gêneros Ocotea (Lauraceae) e Eugenia (Myrtaceae) sobre o ácaro rajado (Tetranycus urticae)

• Autor(a) principal: MORAES, Marcílio Martins de
• Data de Publicação: 2012
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFRPE
• Texto Completo: http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/6359
• topic: Atividade acaricida; Ocotea (vegetal); Eugenia (vegetal); Óleo essencial; Ácaro rajado; CIENCIAS EXATAS E DA TERRA::QUIMICA

The present study aims to investigate the chemical composition of essential oil from leaves of Ocotea duckei and Ocotea glomerata and leaves and fruits of Eugenia langsdorffii by GC-FID and GC-MS and to evaluate the acaricide action of essential oils and their compounds (separately and as blends) on the Tetranycus urticae.The oils from the leaves of species of the genus Ocotea were characterized by high percentage of sesquiterpenes. The main compounds identified were β-caryophyllene (18.6 ± 0.1%) and valenceno (17.6 ± 0.0%) for the oil of O. duckei and aromadendrene (17.3 ± 0.6%) and β-caryophyllene (14.6 ± 0.3%) for the oil of O. glemerata. The oils from leaves and fruits of E. langsdorffii were characterized by high percentage of sesquiterpenes. Epi-longipinanol (13.6 ± 0.1%) and -eudesmol (12.3 ± 0.2%) were the main components of oil from the leaves, while 10-epi-- eudesmol (35.7 ± 0.3%) and 1,10-di-epi-cubennol (15.6 ± 0.3%) were the major identified in the oil of the fruits. All oils tested were toxic to T. urticae. The oil of O. duckei (LC50 = 0.52 mL L-1from air) showed 2.5 times more toxic than the oil of O. glomerata fumigation test and 1.5 times more toxic than the oil of O. glomerata (LC50 = 7.22 mL / mL) in the residual contact test. The oil from the leaves of E. langsdorffii (LC50 = 1.7 mL L-1 air) was 1.7 times more toxic than the oil of the fruit by fumigation, and 1.8 times less toxic by residual contact. The fumigation toxicity observed for all oils was much lower compared with the positive control (eugenol). However, the effect of residual contact of the oils from the leaves of O. duckei, O. glomerata and the fruits of E. langsdorffii were only 2.5, 4.0 and 6.7 times lower than that of eugenol. The relationship between property acaricide, constituents and the blends of all the oils investigated in this work is also discussed.