Detection of hypericins in the "red glands" of Hypericum elodes by ESI-MS/MS.

The biologically active naphthodianthrones hypericin and pseudohypericin were detected by electrospray ionization mass spectrometry (ESI-MS/MS) in microsamples from the sepals of Hypericum elodes (Hypericaceae) containing the so-called "red glands", i.e. stipitate glands with red-coloured heads. The occurrence of hypericins in the red glands of H. elodes supports the taxonomic position of the section Elodes within the genus Hypericum and provides evidence that the ability of carrying out the biosynthetic pathway leading to the naphthodianthrone compounds, rather than the absolute amounts produced, should be regarded as a chemical marker of the phylogenetically more advanced sections of genus Hypericum. The biologically active phloroglucinol derivatives hyperforin and adhyperforin, so far found only in H. perforatum, were also detected and evidence for their localization in the sepal secretory canals with large lumen, is given.