Novel xanthones from Securidaca longepedunculata with activity against erectile dysfunction.

ABSTRACT

AIM OF STUDY Securidaca longepedunculata is used in the treatment of erectile dysfunction in South Africa. The aim of the study was to isolate and identify the active constituents and to determine their activity in the relaxation of corpus cavernosal smooth muscle. MATERIALS AND METHODS: Bioassay guided isolation of the bioactive compounds using a smooth muscle relaxation bioassay and structural elucidation was carried out using different spectroscopic techniques including 2D NMR. RESULTS: Two new xanthones were isolated; one of them showed potent activity to relax the corpus cavernosal smooth muscle by 97 % in comparison to sildenafil (Viagra) at 1.8 x 10(-5) mg/ml. CONCLUSIONS: S. longepedunculata's xanthones stimulate the relaxation of corpus cavenosum smooth muscle, which supports the traditional use of its root bark.