RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Ageratum conyzoides L. is a plant widely used in traditional medicine in tropical and subtropical regions of the world due to its anti-inflammatory, antinociceptive and antibacterial properties. AIM OF THE STUDY: To characterize the standardized extract of polymethoxyflavones (SEPAc) from the plant and evaluate its antinociceptive and anti-inflammatory effects. MATERIALS AND METHODS: The SEPAc purified from the ethanol extract of the plant leaves was characterized by high resolution mass spectrometry and the methoxyflavones were quantified by a validated UPLC-PDA method. The antinociceptive and anti-inflammatory activities of the SEPAc were evaluated after oral administration on the acute nocifensive behavior of mice induced by formalin, prostaglandin E2 (PGE2) and proinflammatory cytokines (interleukin-1beta (IL-1ß)) and tumor necrosis factor-alpha (TNF-α) in mice. RESULTS: Qualitative analyses revealed the presence of seven methoxyflavones in the SEPAc, also a simple UPLC-PDA method was developed and validated for the quantification of 5,6,7,3',4',5'-hexametoxyflavone; nobiletin; 5'-methoxynobiletin and eupalestin, major compounds in the extract. The SEPAc exhibited antinociceptive and anti-inflammatory activities in both formalin phases, with significant inhibition of the paw edema formation and significant reduction of the nocifensive response induced by an intraplantar injection of PGE2 and intrathecal injection of interleukin-1ß. CONCLUSIONS: The SEPAc exhibited significant antinociceptive and anti-inflammatory effects. These results provided scientific suggestion of its potential as a source of new medicines to treat inflammatory diseases, such rheumatoid arthritis.

Assuntos

RESUMO

Long-range coupling constants (5) JHortho,OMe were measured in series of methoxyindoles, methoxycoumarins, and methoxyflavones by the modified J doubling in the frequency domain method. The COSY and NOESY spectra revealed the coupling of the -OMe group with a specific proton at the ortho position and its preferred conformation. Homonuclear (1) H-(1) H couplings were confirmed by irradiation of the -OMe signal. Density functional theory calculations of (5) JHortho,OMe using the modified aug-cc-pVTZ basis set evidenced that the Fermi contact term shows good agreement with the experimental J values. Accurate chemical shift and coupling constant values followed after iterative quantum mechanical spectral analysis using the PERCH software.

RESUMO

Tuberculosis (TB), caused by Mycobacterium tuberculosis, is the world's number one killer among infectious diseases. The search for new naturalproducts that can act as drugs against TB has received increased attention duringthe last years. In this work we describe the isolation and identification of the active antimycobacterial principles of the dichloromethane extract from Lippia lacunosa Mart. & Schauer, Verbenaceae. Compounds were evaluated for their in vitro activity against Mycobacterium tuberculosis (susceptible and rifampicin resistantstrain) using a redox bioassay. From the dichloromethane extract of L. lacunosa leaves, seven methoxy-flavones named cirsimaritin (1), eupatilin (2), eupatorin (3), salvigenin (4), 3'-O-methyl-eupatorin (5), 3',7-dimethoxy-5,6,4'- trihydroxyflavone (6), and 7'-O-methylapigenin (7), and one triterpene, named oleanolic acid (8), were isolated. All compounds were found to display antimycobacterial activity against susceptible strain, with MIC ranging from 25 to 200 µg/mL. None of them was active against rifampicin resistant strain. This is the first report in the antimycobacterial activity of 6-substituted flavones, as well as the first report of the occurrence of these substances in L. lacunosa.