Chemical investigation of the medicinal and ornamental plant Angelonia angustifolia Benth. reveals therapeutic quantities of lupeol.

Angelonia angustifolia Benth. is a small herbaceous plant with documented use as an anti-inflammatory remedy by indigenous cultures in Latin America. It has subsequently been developed as an ornamental annual widely available in nurseries in the United States. Chemical investigation led to the discovery that lupeol is the major organic soluble constituent in the roots, and is present in large quantities in the aerial structures of the plant. Lupeol was identified by 1D and 2D NMR spectroscopic techniques and quantified by HPLC-MS. The concentration of lupeol (9.14 mg/g in roots) in A. angustifolia is approximately 3 times higher than any previously reported sources. Therefore, the amount of lupeol in the roots of a single individual of A. angustifolia greatly exceeds the previously determined topical threshold for significant reduction of inflammation. The presence of topically therapeutic levels of lupeol in A. angustifolia provides chemical rationale for its indigenous use. In addition, the established cultivation of A. angustifolia could allow this plant to be used as a source of the important bioactive molecule lupeol, or to be developed as a nutraceutical without damaging wild populations.