Preparation of an extract (I) from a plant from the Turneraceae family, comprises extracting plant parts with an extracting agent, which contains water and an organic solvent (methanol, ethanol, propanol, isopropanol and/or acetone)； concentrating the extract to a thick extract； and enriching lipophilic substances to the concentrate. An independent claim is included for the extract obtained by the above process. ACTIVITY : Vasotropic； Antidiabetic. MECHANISM OF ACTION : Human phosphodiesterase V (PDE-V) inhibitor. (I) (from T. aphrodisiaca) was tested for its PDE-V inhibitory activity by a tritium scintillation proximity assay. The results showed that the median inhibitory concentration of (I) was 10-15 mu g/ml.
