Planta Med 2013; 79 - PA19
DOI: 10.1055/s-0033-1351923

Ocotea notata extracts: chemical profile and in vitro antimycobacterial activity

IF Borges 1, RV Pereira 1, M Heggdorne-Araújo 1, E Lassounskaia 2, RO De Souza 3, IC Leal 4, MF Muzitano 1
  • 1Laboratório de Produtos Naturais- Federal University of Rio de Janeiro/Macaé
  • 2Laboratório de Biologia do Reconhecer (LBR)- Campo dos Goytacazes- UENF/Rio de Janeiro
  • 3Biocatalysis and Synthesis Organic Group- Federal University of Rio de Janeiro/Rio de Janeiro
  • 4Laboratório de Produtos Naturais- Federal University of Rio de Janeiro/Rio de Janeiro

The Ocotea genus (Lauraceae) is mainly distributed in tropical and subtropical regions. Some species of this genus as O. puberula and O. quixos have been described in literature by exhibiting antibacterial activity. Tuberculosis (TB) is a major challenge worldwide, showing high rates of co-infection with mycobacteria. Our goal was to evaluate the inhibitory effect of O. notata extracts, from Jurubatiba Shoal against TB mycobacteria bacillus. Aerial parts of O. notata were dried, pulverized and soaked for 7 days. The crude extract obtained was subjected to a liquid-liquid partition by using solvents with different polarities and subsequently monitored on thin layer chromatography (TLC). For the ethyl acetate and buthanol fractions there were used butanol: acetic acid: water (BAW) 8:1:1 as mobile phase and NP-PEG as chromogenic reagent. The TLCs were observed in a dark chamber under UV light at wavelengths λ254 and λ365 nm which indicated the presence of flavonoids. The fractions were also analyzed by HPLC-DAD which confirmed the presence of phenolic skeletons by characteristic UV spectra (210, 256 and 352nm). The hexane fraction was analyzed by GC-MS being detected the presence of sesquiterpenes, among them santalol and spatulenol as majors. The biological assay was initially performed by using Mycobacterium bovis BCG, which was distributed in 96 well plate with culture medium 7H9+ADC, 1 × 106 CFU/well. The O. notata samples were added at 0.8; 4; 20 and 100 µg/mL and rifampicin used as control. The plate was incubated for 7 days and mycobacterial growth quantified by the MTT method (n = 3, Statistical: ANOVA). At the concentrations tested it was observed that the leaf crude extract was able to inhibit 81.9 ± 6.48% at 100 µg/mL and the hexane and ethyl acetate fractions to inhibit 72.9 ± 9.72% and 48.5 ± 0.29% at 100 µg/mL, respectively. These results suggest that the constituents present in the active fractions may be promising to the search for new agents against M. bovis.