Efeitos de substâncias elicitoras sobre o acúmulo de metabólitos secundários em plantas jovens de Picrolemma sprucei Hook. f. (Simaroubaceae), uma espécie medicinal da Amazônia utilizada contra a malária

Abstract

The human malaria, one of the most debilitating diseases in the world, remains endemic in tropical regions despite intensive control programs in an attempt to combat it. The increasing spread of antimalarial drug resistance became necessary new drugs against the disease. Picrolemma sprucei Hook. f. (synonym P. pseudocoffea Ducke) is a native shrub and an important medicinal plant from the Amazon Region. The plant has been used in traditional medicine to treat malaria. Its main chemical compounds, the quassinoids isobrucein B and neosergeolide, have presented high in vitro and in vivo antiplasmodial activity. Nevertheless, it´s not know about the production seasonality of these metabolites by the plant, nor the development stage that the plant start to produce them. This study quantified and compared the production of the quassinoids isobrucein B and neosergeolide in P. sprucei plants of in vitro germination, in natural populations of young plants and in green house seedlings maintained in elicitation with methyl jasmonate, methyl salicylate and salicylic acid for 24, 48 and 72 hours, using High Performance Liquid Chromatography, Thin Layer Chromatography and Densitometry. The results showed that in vitro seedlings, after 120 days, presented no detectable quantities of quassinoids. The natural young plants population presented different amounts of quassinoids (up to 0.95% for isobrucein B and 2.37% for neosergeolide) in different parts of the plant. The methyl salicylate has shown to be the best tested elicitor, stimulating an accumulation up to 5.37% of isobrucein B in roots and up to 9.28% of neosergeolide in leaves. Keywords: biotechnology; tissue culture; quassinoids dosages; in vivo secondary metabolites stimulation; isobrucein B; neosergolide.