Co-occurrence of phenylphenalenones and flavonoids in Xiphidium caeruleum Aubl. flowers.

A Xiphidium caeruleum flower extract was separated by semi-preparative HPLC into five fractions, from which three flavonoids, two phenylphenalenones and 17 phenylphenalenone-related compounds including five unknown compounds, were isolated and their structures elucidated by Liquid Chromatography-Diode Array Detection-Solid Phase Extraction-Nuclear Magnetic Resonance spectroscopy (LC-DAD-SPE-NMR) and mass spectrometry (MS). This is the first report of the co-occurrence of phenylphenalenones and flavonoids in the Haemodoraceae family. The ecological implications of flavonoids and various phenylphenalenone-type compounds and their putative biosynthesis sites in X. caeruleum are subject to discussion.