Portal de Periódicos da CAPES

Artigo Produção Nacional Revisado por pares

BIBTEX RIS

Grain-protectant compounds from Duguetia lanceolata (Annonaceae) derivatives: Bioassay-guided searching and toxicity against the maize weevil

2019; Elsevier BV; Volume: 85; Linguagem: Inglês

10.1016/j.jspr.2019.101549

1879-1212

Vanessa de Cássia Domingues, Leandro do Prado Ribeiro, Gabriel Luiz Padoan Gonçalves, Moacir Rossi Forim, Maria Fátima das Graças Fernandes da Silva, João Batista Fernandes, José Djair Vendramim,

Allelopathy and phytotoxic interactions

In order to obtain bioactive allelochemicals from Neotropical Annonaceae, bioguided chromatographic fractionations with derivatives prepared from Duguetia lanceolata St.-Hil. leaves were performed using the maize weevil, Sitophilus zeamais Mots. (Coleoptera: Curculionidae), as bioindicator, which is a primary insect pest of stored cereals in tropical conditions. For this end, four phases (hexane, dichloromethane, ethyl acetate and hydroalcohol) were obtained firstly by liquid-liquid partition and tested through a residual contact bioassay (at 1500 mg L−1) in order to verify their bioactivity on adults of the maize weevil. Only the hexanic fraction caused significant mortality (74%) after the tenth day of insect exposure on treated samples of grains corn. Thus, thisfraction was separated into seven new subfractions by means of vacuum column chromatography and solvents of increasing polarities. Subfraction 2 promoted 90% of mortality whereas subfraction 6 promoted 30% of mortality of maize weevils. The aromatic compound 2,4,5-trimethoxystyrene and a mixture of steroids [campesterol (8.44%) + stigmasterol (12.37%) + sitosterol (79.19%)] were isolated from subfraction 2 and promoted promising grain protective activity, in a manner comparable to a diatomaceous-earth based formulation (our positive control). Furthermore, the results reported in the present study demonstrate the potential application of derivatives of D. lanceolata leaves in integrated pest management (IPM) of stored grains, mainly in the framework of maize weevil management.