RESUMO
The aerial parts of L. cultratus were submitted to a phytopharmacological investigation in order to isolate and identify the major secondary metabolites and evaluate its crude extract, fractions and isolated compounds for antiproliferative activity. Seven compounds were isolated and identified as the chalcones 2',4'-dihydroxy-5'-prenylchalcone (1) and isocordoin (2), the flavanone 8-prenylpinocembrin (3), the alkaloid 4-hydroxy-N-methylproline (4), the triterpenes lupeol and lupenone. These compounds were identified by nuclear magnetic resonance of 1H and 13C data in comparison with literature. Hexanic fraction and chalcone 2',4'-dihydroxy-5'-prenylchalcone showed potent results against human cancer cell lines tested.
Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Fabaceae/química , Catecóis/química , Catecóis/farmacologia , Proliferação de Células/efeitos dos fármacos , Chalconas/química , Chalconas/isolamento & purificação , Chalconas/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Fabaceae/metabolismo , Humanos , Células K562 , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Triterpenos Pentacíclicos/química , Triterpenos Pentacíclicos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Plantas Medicinais/metabolismo , Metabolismo Secundário , Triterpenos/química , Triterpenos/farmacologiaRESUMO
It is known that plant and associated bacteria coevolved, but just now the roles of chemical signaling compounds in these intricate relationships have been systematically studied. Many Gram-negative bacteria produce N-acyl-L-homoserine lactones (AHL), chemical signals used in quorum-sensing bacterial communications mechanisms. In recent years, it has been shown that these compounds may also influence the development of plants, acting as allelochemicals, in still not well understood eukaryot-prokaryot interactions. In the present work, a quorum-sensing molecule produced by the tomato associated bacterium Pseudomonas sp. was characterized and its effects on germination and growth of tomato seedlings were accessed. The chemical study of the bacterium extract led to the identification of N-3-oxo-dodecanoyl-L-homoserine lactone (1), using gas chromatography coupled to electron impact mass spectrometry (GC-MS), and ultra-high resolution Qq-time-of-flight mass spectrometry (UHR-QqTOF-MS) equipped with an electrospray ionization source (ESI). The synthetic compound was tested at different concentrations in tomato to evaluate its effects on seed germination and seedlings root growth. Inhibition of tomato seed germination and root growth were observed in the presence of micromolar concentrations of the compound 1. Scanning electron microscopy evidenced morphological alterations on roots in the presence of the compound, with reduction of growth, impaired root hairs development and cracks in the rhizodermis.
