Planta Med 2014; 80 - P1L160
DOI: 10.1055/s-0034-1394817

Bioactive compounds from the stem bark of Croton heliotropiifolius

MMF Queiroz 1, 2, EF Queiroz 1, ML Zeraique 2, G Marti 1, Q Favre-Godal 1, CA Simões-Pires 1, L Marcourt 1, M Cuendet 1, MQ Paulo 3, VS Bolzani 2, JL Wolfender 1
  • 1School of Pharmaceutical Sciences, University of Geneva, University of Lausanne, 30, Quai Ernest-Ansermet, CH-1211 Geneva 4, Switzerland
  • 2Núcleo de Bioensaios, Biossíntese e Ecofisiologia de Produtos Naturais, NuBBE, Instituto de Química, UNESP, Araraquara, São Paulo, Brazil
  • 3Laboratório de Química de Produtos Naturais, Universidade Federal da Paraíba, UFPB, João Pessoa, Paraíba, Brazil

The ethanolic extract of the stem barks of Croton heliotropiifolius Kunth (Euphorbiaceae) showed significant inhibition of acetylcholinesterase and antifungal activity against Candida albicans on thin layer chromatography bioautographic assays [1,2]. In order to target the isolation of the active compounds at a large scale, HPLC-activity-based-microfractionation in 96 well plates was used in a first step to localize the active compounds. Different regions of the HPLC-UV chromatogram were linked to the acetylcholinesterase inhibition and antifungal activities. Some active compounds were dereplicated by HPLC-PDA-ESI-MS and UHPLC-TOF-HRMS. The target isolation of the active compounds was performed by medium pressure liquid chromatography (MPLC-UV) and semi-preparative HPLC. Using this approach, nine compounds were isolated: one new indole alkaloid derivative, 6-hydroxy-1-(R)-methyl-2-dimethyl-3,4-tetrahydro-β-carboline (1) and several known compounds, (α)-magnoflorine (2), (+)-menisperine (3), taspine (4), moschamine (5), n-propylparaben (6), velamolone acetate (7), spruceanol (8), velamone (9). The isolated compounds presented in the activity region were tested at various concentrations against two strains of C. albicans; the mutant strain (DSY2621) and the wild strain (CAF21). Spruceanol (8) was the most active compound demonstrating an interesting antifungal activity with a minimal inhibitory quantity (MIQ) of 2 µg against the mutant strain, and 10 µg against the wild strain. The AChE inhibitory activity of the isolated compounds was measured and the IC50 values calculated. Compounds 4 and 5 showed the highest AChE inhibitory activity with IC50 values below 10µM. Compounds 1-3 exhibited moderate activity compared to the positive control galanthamine.

References:

[1] Marston A, Kissling J, Hostettmann K. A rapid TLC bioautographic method for the detection of acetylcholinesterase and butyrylcholinesterase inhibitors in plants. Phytochem Anal 2002; 13: 51 – 54.

[2] Favre-Godal Q, Queiroz EF, Wolfender JL. Latest developments in assessing antifungal activity using TLC bioautography. JOAC International 2013; 96: 1175 – 1188.