Estudo químico e biológico de Penicillium paradoxum

Abstract

The rich Amazonian biodiversity is a precious reservoir of bioproducts and may contain the solution to several problems in modern society, such as the excessive use of pesticides. In this context, the objective of this work was to evaluate the bioherbicidal potential of extracts produced by Penicillium paradoxum (I1CXS1C1), isolated from mining waste. From cultivation in rice medium, hexane, dichloromethane and methanolic extracts were produced. All extracts were subjected to bioassays aimed at inhibiting the germination of Brachiara decumbens seeds. The experiments were carried out over a period of 10 days, a 12- hour photoperiod and a temperature around 25 ºC. For each extract, solutions were prepared in different concentrations (m/v) according to the treatments of interest: 0.5%, 1.0%, 1.5% and 2.0% (m/v). The experiment was conducted in the presence of water, hexane, dichloromethane and methanol controls. For preliminary evaluation of the chemical profile of the extracts, they were subjected to high-performance chromatographic analysis. From the bioassays carried out, contrary to expectations, the majority of treatments favored seed germination, with emphasis on the hexane extract with an accumulated germination rate of 53.75%, being higher than all rates recorded for controls. When it comes to the chemical profile of the extracts, polar substances with good absorption in the 254 nm range predominate. Despite being preliminary, the results observed motivate the carrying out of new tests with a view to proving the phytohormonal effect of the extracts.